Copy of A&P FINAL EXAM STUDY GUIDE

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PN 103 Anatomy and Physiology Final Exam Study Guide FALL 2023/ SCHMITT Chapter 20 Fluid, Electrolyte, & Acid-Base Balance Discuss how the water moves between compartments Fluid doesn’t remain locked within a single compartment. Rather, ICF and ECF continually mingle, as the fluid easily passes through the semipermeable membrane surrounding each compartment. The concentration of solutes (particularly electrolytes) within each compartment determines the amount and direction of flow. For example: If the concentration of electrolytes (and therefore the osmolarity) of tissue fluid rises, water moves out of the cells and into the tissues. If the osmolarity of tissue fluid falls, water moves out of the tissues and into the cells. The passage of fluid happens within seconds so as to maintain equilibrium Explain the intake and output of water To keep the total volume of water in the body in balance, the body uses mechanisms that adjust fluid intake as well as urine output. Various factors, including excessive sweating, cause the volume of total body water to decline. Blood pressure drops, sodium concentration rises, and osmolarity increases. Mechanisms to increase fluid intake - Physical changes stimulate the thirst center in the hypothalamus - Salivation decreases, causing a dry mouth and the sensation of thirst Consumption of water leads to a rise in total water volume Mechanisms to decrease urine output - Physical changes stimulate the hypothalamus, which, in turn, stimulates the posterior pituitary to secrete antidiuretic hormone (ADH) - ADH prompts the collecting ducts of the kidneys to reabsorb more water and produce less urine - The rate of fluid loss slows until water is ingested When blood volume and pressure are too high, or blood osmolarity is too low, the hypothalamus inhibits the release of ADH. This causes the renal tubules to reabsorb less water, leading to an increased urine output and a decline in total body water. Describe the disorders of water balance A water imbalance can result from an abnormality in any of the following: fluid volume, fluid concentration, or the distribution of fluid between compartments. Fluid Deficiency A fluid deficiency occurs when output exceeds intake over a period of time. There are two types of fluid deficiency: volume depletion (hypovolemia) and dehydration. Volume depletion results from blood loss or when both sodium and water are lost, such as from diarrhea. Dehydration results when the body eliminates more water than sodium. Not only is there a loss of fluid, the concentration of sodium (and the osmolarity) of the extracellular fluid (ECF) also
rises. The increase in osmolarity prompts the shifting of fluid from one compartment to another in an effort to balance the concentration of sodium. Basically, dehydration results from consuming an inadequate amount of water to cover the amount of water lost. Other causes include diabetes mellitus and the use of diuretics. When severe, fluid deficiency can lead to circulatory collapse (hypovolemic shock) as a result of loss of blood volume. Dehydration affects all fluid compartments. For example, if you exercise strenuously on a hot day, you will lose a significant amount of water through sweat. The water in sweat comes from the bloodstream. As water shifts out of the bloodstream, the osmolarity of the blood rises. To compensate, fluid moves from the tissues into the bloodstream. The loss of fluid from the tissues causes the osmolarity of the fluid in this space to rise. If the imbalance continues, fluid will shift out of the cells and into the tissues, resulting in a depletion of intracellular fluid. Consequently, dehydration affects the bloodstream, tissues, and cells. Fluid Excess The kidneys usually compensate for excessive fluid intake by producing more urine; consequently, fluid excess occurs less commonly than fluid deficit. However, when a fluid excess does occur, it can be life-threatening. One cause of fluid excess is renal failure. (In this instance, both sodium and water are retained, and the ECF remains isotonic.) Another type of fluid excess is called water intoxication. Water intoxication can occur if someone consumes an excessive amount of water or if someone replaces heavy losses of water and sodium (such as from profuse sweating) with just water. When this occurs, the amount of sodium in the ECF drops. Water moves into the cells, causing them to swell. Possible complications of either type of fluid excess include pulmonary or cerebral edema. Fluid Accumulation Another type of water imbalance involves the accumulation of fluid within a body compartment. For example, edema occurs when fluid accumulates in interstitial spaces, causing tissues to swell. Even though fluid can accumulate in any organ or tissue in the body, it typically affects the lungs, brain, and dependent areas (such as the legs). A disturbance in any of the factors regulating the movement of fluid between blood plasma and the interstitial compartment—such as electrolyte imbalances, increased capillary pressure, and decreased concentration of plasma proteins—can trigger edema. Name the major electrolytes in body fluids The major cations of the body are sodium (Na), potassium (K), calcium (Ca2), and hydrogen (H). The major anions are chloride (Cl), bicarbonate (HCO3), and phosphates (Pi). Explain the buffer system The body employs various mechanisms, called buffers, to keep acids and bases in balance. A buffer is any mechanism that resists changes in pH by converting a strong acid or base into a weak one. There are two categories of buffers: chemical buffers and physiological buffers. Not all the buffer systems begin working at the same time. Chemical buffers respond first, followed by the respiratory system and, finally, the renal system. • When blood plasma pH rises to more than or falls to less than normal, chemical buffers respond instantaneously. Chemical buffers often restore blood plasma to a normal pH within a fraction of a second.
• If pH remains outside the normal range for more than 1 to 2 minutes, the respiratory system changes the rate and depth of breathing. This adjusts the amount of CO2, which, in turn, alters H ion concentration and helps stabilize pH. • If pH continues outside the normal range despite involvement of chemical buffers and the respiratory system, the renal physiological buffer system becomes involved. The renal system can neutralize more acids or bases than either of the other systems; however, it’s the slowest to respond, taking as long as 24 hours to be initiated. Explain acidosis and alkalosis (metabolic and respiratory) and the effects on the body Maintaining the body’s normal pH range of 7.35 to 7.45 depends on a precise ratio of bicarbonate ions to carbonic acid. Causes of Acid Gain (Acidosis) Respiratory : • Retention of CO2 (hypoventilation—such as from emphysema or pneumonia— as well as apnea) Renal/Metabolic : • Increased production of acids (such as ketone bodies in diabetes mellitus or lactic acid in anaerobic metabolism) • Consumption of acidic drugs (such as aspirin) • Inability of the kidneys to excrete H ions • Loss of bicarbonate (such as chronic diarrhea or overuse of laxatives) Causes of Acid Loss (Alkalosis) Respiratory : • Loss of CO2 (hyperventilation) Metabolic : • Loss of gastric juices (such as through vomiting or suctioning) • Excessive ingestion of bicarbonates (such as antacids) High H ion concentration depresses the CNS, which is why acidosis causes symptoms such as disorientation, confusion, and coma. Alkalosis, on the other hand, makes the nervous system more excitable, resulting in symptoms such as tetany and convulsions. Chapter 23 Reproductive Systems Name the primary and secondary sex organs Primary sex organs • Primary sex organs are called gonads; they include: • testes in males • ovaries in females • The gonads produce sex cells (gametes); these include: • sperm in males • eggs (ova) in females Secondary sex organs • Secondary sex organs encompass all other organs necessary for reproduction. • In males, this includes a system of ducts, glands, and the penis, all of which are charged with storing and transporting sperm. • In females, the secondary sex organs are concerned with providing a location for the uniting of egg and sperm as well as the environment for nourishing a fertilized egg. Describe spermatogenesis and oogenesis
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Sperm begin as spermatogonia, primitive sex cells with 46 chromosomes located in the walls of the seminiferous tubules. Spermatogonia divide by mitosis to produce two daughter cells, each with 46 chromosomes. These cells then differentiate into slightly larger cells called primary spermatocytes, which move toward the lumen of the seminiferous tubule. Through meiosis, the primary spermatocyte yields two genetically unique secondary spermatocytes, each with 23 chromosomes. Each secondary spermatocyte divides again to form two spermatids. Spermatids differentiate to form heads and tails and eventually transform into mature spermatozoa (sperm), each with 23 chromosomes. Low levels of estrogen and progesterone stimulate the hypothalamus to release GnRH. GnRH stimulates the anterior pituitary to release FSH and LH. FSH triggers several of the follicles in the ovary to resume development, beginning what is known as the follicular phase. Usually, only one follicle will make it to maturity. As the follicle develops, it secretes estrogen (which stimulates the thickening of the endometrium in the menstrual cycle) as well as small amounts of progesterone. As the follicle matures, it migrates to the surface of the ovary. The mature follicle is called a graafian follicle. In the mid-point of the cycle, estrogen levels peak, triggering a spike in LH. The sudden spike in LH causes the follicle to rupture and release the ovum—a process called ovulation. The fimbriae of the fallopian tube sweep across the top of the ovary to catch the emerging oocyte. Describe the male reproductive system The male reproductive system serves to produce, transport, and introduce mature sperm into the female reproductive tract, which is where fertilization occurs. Testes Accessory Glands The male reproductive system includes three sets of accessory glands: the seminal vesicles, prostate gland, and bulbourethral glands. Penis Sperm Describe the female reproductive system The female’s reproductive system does more than produce gametes. It is also charged with carrying, nourishing, and giving birth to infants. Unlike the male, the organs of the female reproductive system are housed within the abdominal cavity. The female’s primary reproductive organs (gonads) are the ovaries. The ovaries produce ova, the female gametes. The accessory organs— which include the fallopian tubes, uterus, and vagina—extend from near the ovary to outside the body. The wall of the uterus has two key roles: housing and nourishing a growing fetus and expelling the fetus from the body during delivery. The uterine wall consists of three layers that aid in those tasks: • The outer layer—called the perimetrium—is a serous membrane.
• A thick middle layer—called the myometrium—consists of smooth muscle that contracts during labor to expel the fetus from the uterus. • The innermost layer—the endometrium—is where an embryo attaches. The upper two-thirds portion (called the stratum functionalis) thickens each month in anticipation of receiving a fertilized egg. If this doesn’t occur, this layer sloughs off, resulting in menstruation. The layer underneath—the stratum basalis—attaches the endometrium to the myometrium. It does not slough off; rather, it helps the functionalis layer regenerate each month. Describe the menstrual cycle The hormones estrogen and progesterone—which are secreted by the ovaries—drive the menstrual cycle. This cycle involves the buildup of the endometrium (which occurs through most of the ovarian cycle) followed by its breakdown and discharge. The menstrual cycle is divided into four phases: the menstrual phase, proliferative phase, secretory phase, and premenstrual phase. A woman’s cycle is typically 28 days Phase 1: Menstrual - Days 1 to 5 The first day of noticeable vaginal bleeding The endometrium sheds its functional layer Phase 2: Proliferative - Days 6 to 14 When menstruation ceases Only stratum basalis remains in the uterus. ~Day 6, rising estrogen levels stimulate the repair of the stratum basalis (base layer), + the growth of blood vessels Endometrium thickens to 2 to 3 mm. Phase 3: Secretory - Days 15 to 26 Increased progesterone from the corpus luteum, thickens functional layer Endometrium develops into the perfect home for a fertilized ovum ~5 - 6 mm thick Phase 4: Premenstrual - Days 26 to 28 If fertilization doesn’t occur, corpus luteum atrophies, progesterone levels plummet Blood vessels to the endometrium spasm, interrupting blood flow Endometrium becomes ischemic and necrotic, causing slough off the uterine wall forming the menstrual flow. Discuss the hormones of the male and female reproductive system After puberty, testosterone is continually secreted throughout the life of the male. Testosterone controls spermatogenesis and supports the male sex drive. Blood levels of testosterone are controlled through a negative feedback loop: • High levels of testosterone inhibit secretion of GnRH by the hypothalamus. This depresses secretion of LH by the anterior pituitary, and testosterone production declines. • Low testosterone levels stimulate the anterior pituitary to increase secretion of LH, which triggers the interstitial cells to step up testosterone secretion.
Just as in males, female puberty is triggered by rising levels of gonadotropin-releasing hormone (GnRH). GnRH stimulates the anterior lobe of the pituitary to secrete follicle-stimulating hormone (FSH) and luteinizing hormone (LH). FSH stimulates the development of ovarian follicles; in turn, ovarian follicles secrete estrogen and progesterone. Estrogen is the hormone responsible for producing the feminine physical changes that occur during puberty, such as development of breasts; deposition of fat beneath the skin of the hips, thighs, and buttocks; and widening of the pelvis. Chapter 24: Pregnancy & Human Development Chapter 25: Heredity Describe the process of fertilization As hundreds of sperm swarm the egg, the acrosomes on the sperm heads release enzymes that break down the cells and the zona pellucida. Because of the efforts of multiple sperm, a path through the zona pellucida eventually results, allowing a single sperm to penetrate. As soon as this happens, the egg undergoes changes that bar any other sperm from entering. The nucleus of the sperm is released into the ovum as its tail degenerates and falls away. The nucleus of the sperm (which has 23 chromosomes) fuses with the nucleus of the egg (which also has 23 chromosomes), creating a single cell with 46 chromosomes. The fertilized egg is now called a zygote. Explain when, where, and how implantation of the embryo takes place The process of implantation takes about a week, being completed about the time the next menstrual period would have occurred if the woman had not become pregnant. As the blastocyst attaches to the endometrium, it continues to change rapidly as it moves toward becoming an embryo. When the blastocyst attaches to the endometrium, the trophoblast cells on the side of the endometrium divide to produce two layers of cells. The outer layer secretes enzymes that erode a gap in the endometrium. As these outer cells penetrate the endometrium, the inner cell mass separates from the trophoblast, creating a narrow space called the amniotic cavity. The inner cell mass flattens to form the embryonic disc. Some of the cells on the interior portion of the embryonic disc multiply to form another cavity, called the yolk sac. Meanwhile, the rapidly growing endometrium covers the top of the blastocyst, burying it completely. The embryonic disc gives rise to three layers, called germ layers, which produce all the organs and tissues of the body. The three germ layers are the ectoderm, mesoderm, and endoderm. Define the stages of prenatal fetal development The union of egg and sperm ignites a period of development that ends with the birth of a baby. This period of growth before birth is called the prenatal period. During this time, the fetus undergoes three major stages of development: ● The preembryonic stage, which begins at fertilization and lasts for 16 days ● The embryonic stage, which begins after the sixteenth day and lasts until the eighth week ● The fetal stage, which begins the eighth week and lasts until birth
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Describe the function and structure of the placenta and umbilical cord The fetal stage begins the eighth week, and, by the twelfth week, the placenta is the fetus’ sole source of nutrition. Although the mother’s blood furnishes the developing fetus with nutrients, maternal and fetal blood do not mix. Instead, chorionic villi are filled with fetal blood and surrounded by maternal blood, separated by a thin layer of placental cells. Some toxins such as nicotine, alcohol, and most drugs can cross this barrier. When they do, they can have a devastating effect on fetal development. Fetal waste products move from fetal blood in the umbilical arteries to the maternal blood; the maternal veins carry away the waste for disposal. Oxygen, nutrients, and some antibodies pass from the maternal blood—which is pooled in the lacunae around the chorionic villi—to fetal blood in the umbilical veins of the placenta. The placenta also serves an endocrine function, secreting hormones (such as estrogen, progesterone, and HCG) necessary for the continuation of the pregnancy. In addition, recent research has shown that the placenta—long thought to be sterile—contains bacteria, creating what appears to be a unique bacterial microbiome. This finding indicates that colonization of the infant’s microbiome begins while in utero. plays a dual role: it secretes hormones necessary to maintain the pregnancy; it also becomes increasingly important in supplying the embryo, and later the fetus, with oxygen and nutrition. The placenta actually begins to form during implantation when specialized cells in the trophoblastic layer extend into the endometrium. As the villi project deeper into the endometrium, they penetrate uterine blood vessels, causing maternal blood to pool around the villi in sinuses called lacunae. Eventually, blood vessels from the umbilical cord extend into the villi, effectively linking the embryo to the placenta. The umbilical cord contains two umbilical arteries and one umbilical vein. Eventually, the fetal heart pumps blood into the placenta via the umbilical arteries; the blood returns to the fetus by way of the umbilical vein. Explain the gestation period. Week 4 • The brain, spinal cord, and heart begin to develop. • The gastrointestinal tract begins to form. • The heart begins to beat about day 22. • Tiny buds that will become arms and legs are visible. • Length: 0.25 inch (0.6 cm) Week 8 • The embryo is now a fetus. • Eyes, ears, nose, lips, tongue, and tooth buds take shape. • Head is nearly as large as the rest of the body. • Brain waves are detectable. • Arms and legs are recognizable. • Blood cells and major blood vessels form. • Bone calcification begins.
• Genitals are present but gender is not distinguishable. • Length: 1.2 inches (3 cm) Week 12 • The face is well formed. • Arms are long and thin. • Gender is distinguishable. • The liver produces bile. • The fetus swallows amniotic fluid and produces urine. • Eyes are well developed but the eyelids are fused shut. • Length: 3.54 inches (9 cm) Week 16 • The scalp has hair. • Lips begin sucking movements. • The skeleton is visible. • The heartbeat can be heard with a stethoscope. • Kidneys are well formed. • Length: 5.5 inches (14 cm) Week 20 • A fine hair called lanugo covers the body, which, in turn is covered by a white cheese-like substance called vernix caseosa; both these substances protect the fetus’ skin from amniotic fluid. • Fetal movement (quickening) can be felt. • Nails appear on fingers and toes. • Length: 8 inches (20 cm) Week 24 • The fetus has a startle reflex. • Lungs begin producing surfactant, a lipid and protein mixture that reduces alveolar surface tension. • Skin is wrinkled and translucent. • The fetus gains weight rapidly. • Length: 11.8 inches (30 cm) Week 28 • Eyes open and close. • The respiratory system, although immature, is capable of gas exchange at 28 weeks. • Testes begin to descend into the scrotum. • The brain develops rapidly. • Length: 14.8 inches (37.6 cm) Week 32 • The amount of body fat increases rapidly. • Rhythmic breathing movements begin, although lungs are still immature. • Bones are fully formed, although they are still soft. • Length: 16.7 inches (42 cm) Week 36 • More subcutaneous fat is deposited.
• Lanugo has mostly disappeared, although it’s still present on the upper arms and shoulders. • Length: 18.5 inches (47 cm) Weeks 39 and 40 • The fetus is considered full term. • The average full-term infant measures approximately 20 inches (51 cm) long and weighs 7 to 71/2 lbs (3.2 to 3.4 kg). Identify the stages of labor Labor occurs in three stages known as the dilation, expulsion, and placental stages. Stage 1: Dilation of the Cervix The first stage of labor is the longest stage. It lasts 6 to 18 hours in women giving birth for the first time (primipara); it’s usually shorter in women who have previously given birth (multipara). Key features of this stage are the following: ● Cervical effacement: the progressive thinning of the cervical walls ● Cervical dilation: the progressive widening of the cervix to allow for passage of the fetus Fetal membranes usually rupture during dilation, releasing amniotic fluid; this is often referred to as the water breaking. When the cervix is fully dilated to approximately 4 inches (10 cm), the second stage of labor begins. Stage 2: Expulsion of the Baby The second stage of labor—which begins with full dilation of the cervix and ends when the baby is born—lasts 30 to 60 minutes in primiparous women but can be much shorter in multiparous women. Normally, the head of the baby is delivered first. (The first appearance of the top of the head is called crowning.) To facilitate passage of the head, a surgical incision is sometimes made between the vagina and the anus to enlarge the vaginal opening; this is called an episiotomy. As soon as the head emerges, mucus is cleared from the baby’s mouth and nose to facilitate breathing. The umbilical cord is clamped and cut, and the third stage begins. Stage 3: Delivery of the Placenta The final stage involves delivery of the afterbirth: the placenta, amnion, and other fetal membranes. After delivery of the baby, the uterus continues to contract. These contractions cause the placenta to separate from the uterine wall. As contractions continue, the fetal membranes are expelled from the body. The contractions also help seal any blood vessels that are still bleeding. This stage of labor lasts between 5 and 30 minutes. Describe the physical changes in the neonate Immediately after birth, the neonate’s body undergoes a number of changes as it adapts to life outside the mother’s body. These changes affect most body systems. ● Cardiovascular: Pressure changes in the heart cause the foramen ovale to shut, and pressure changes in the pulmonary artery and aorta lead to the collapse of the ductus arteriosus. (The foramen ovale seals permanently during the first year of life, whereas the ductus arteriosus closes permanently at about 3 months of age.)
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● Respiratory: Although most neonates begin breathing spontaneously, the first few breaths require considerable effort as they work to inflate collapsed alveoli. ● Immune system: Neonates have weak immune systems at birth, placing them at risk for infection. ● Thermoregulation: Neonates risk becoming hypothermic because their surface area, in relationship to their size, is larger than in an adult. ● Fluid balance: Neonates require a fairly high fluid intake because their immature kidneys do not concentrate urine adequately. Differentiate between heredity and genetics This process of passing traits from biological parents to children is called heredity , whereas the study of heredity or inheritance is called genetics . Explain the patterns of inheritance Each chromosome contains anywhere from a few hundred to several thousand genes. The location of a specific gene on a chromosome is called its locus. The locus of each gene does not vary from one person to another. (This allows the genes supplied by the egg to align with similar genes supplied by the sperm.) Even though homologous chromosomes carry the same gene at the same locus, they may carry an alternative form of that gene (called an allele). Alleles produce variations of a trait (such as brown versus blue eyes or curly versus straight hair). An individual may have two alleles that are the same or two alleles that are different. If a person has two alleles that are the same, the person is said to be homozygous for that trait. If the alleles are different, the person is said to be heterozygous. In heterozygous individuals, the trait that becomes detectable (called gene expression) depends on whether the allele is dominant or recessive. A dominant allele overshadows the effect of a recessive allele. Offspring express the trait of a dominant allele if both, or only one, chromosome in a pair carries it. For a recessive allele to be expressed, both chromosomes must carry identical alleles. Some alleles are equally dominant (codominant). In this instance, both alleles are expressed. An example of codominance is the AB blood type. The phenomenon whereby genes at two or more loci contribute to the expression of a single trait is called polygenic inheritance. The genetic information stored at the locus of a gene, even if the trait is not expressed, constitutes a person’s genotype . The detectable, outward manifestation of a genotype is called a phenotype . Describe sex-linked inheritance Some traits, called sex-linked traits, are carried on the sex chromosomes. Almost all of these traits, which are recessive, are carried on the X chromosome—mainly because the X chromosome has much more genetic material than does the Y. If a woman inherits the allele for this condition, the allele on her other X chromosome would overpower the recessive allele. Consequently, she would be a carrier of the trait but would not exhibit any symptoms.
Because a man has only one X chromosome, he does not have a dominant matching allele to overpower the X-linked recessive trait. As a result, that trait would be expressed, and he would be color-blind. The X chromosome carries hundreds of genes, most of which have nothing to do with determining gender. Identify selected common genetic disorders A permanent change in genetic material is known as a mutation. Although mutations may occur spontaneously, they can also result from exposure to radiation, certain chemicals, or viruses. A variety of disorders result from inheriting defective genes. Ranging in severity from mild to fatal, some of these disorders become apparent soon after birth, whereas others don’t reveal themselves for years. A few of the diseases that result from mutations include sickle cell disease, severe combined immunodeficiency syndrome (SCID), phenylketonuria (PKU), Huntington’s disease, and cystic fibrosis. In some diseases (like Huntington’s disease), the defective gene is dominant; in other diseases (like cystic fibrosis), it is recessive. A defective gene on chromosome 7 causes a common and severe inherited disease called cystic fibrosis. In these disorders, large segments of a chromosome, or even entire chromosomes, are missing, duplicated, or otherwise altered. The most common disorders result when homologous chromosomes fail to separate during meiosis. This is called nondisjunction. Most pregnancies involving extra or missing chromosomes end in miscarriage. The most survivable trisomy, and therefore the most common, is Down syndrome or trisomy 21. Define multifactorial disorders Experts believe that nearly all diseases have a genetic component. As previously discussed, some, such as sickle cell disease or cystic fibrosis, result from mutation in a single gene. Most disorders, however, likely result from the effects of multiple genes in combination with lifestyle and environmental factors. Disorders resulting from many contributing factors are called multifactorial disorders . For example, heart disease tends to run in families, meaning it has a genetic link. However, environmental and lifestyle factors (such as diet, exercise, stress, and whether or not a person smokes) also influence the onset and progression of heart disease. Other examples of multifactorial disorders include hypothyroidism, diabetes, and cancer. It also appears that the human microbiome plays a role in regulating genetic expression. To begin, genes within the gut microbiota outnumber genes in the human genome a hundred times. Furthermore, dysbiosis of the gut microbiota is linked to a host of diseases. The complexity of gut microbiota make it challenging to study, but one study suggests that gut microbes may place chemical tags on DNA, altering gene expression. Another hypothesis based on animal research is that the microbiome regulates gene expression by changing accessibility of chromatin in the cells. Key Concepts to know :
Review previous study guides Review the heart, female/male reproductive diagrams. Be able to label parts without a word bank. Be able to identify IM injection sites-deltoid, ventrogluteal, vastus lateralis, rectus femoris. Heart circulation-blood flow through heart-p 300, The right atrium receives deoxygenated blood returning from the body through the superior and inferior vena cavae. Once the right atrium is full, it contracts. This forces the tricuspid valve open and blood flows into the right ventricle. When the right ventricle is full, the tricuspid valve snaps closed to prevent blood from flowing backward into the atria. After filling, the right ventricle contracts, forcing the pulmonary valve open. Blood is pumped into the right and left pulmonary arteries and onto the lungs. After the right ventricle empties, the pulmonary valve closes to prevent the blood from flowing backward into the ventricle. After replenishing its supply of oxygen (and cleansing itself of carbon dioxide) in the lungs, the blood enters the pulmonary veins and returns to the heart through the left atrium. When the left atrium is full, it contracts. This forces the mitral, or bicuspid, valve open and blood is pumped into the left ventricle. When the left ventricle is full, the mitral valve closes to prevent backflow. The ventricle then contracts, forcing the aortic valve to open, allowing blood to flow into the aorta. From there, oxygenated blood is distributed to every organ in the body. Although the right and left sides of the heart act as separate pumps, they perform their work simultaneously. Both the right and left atria contract at the same time, as do both ventricles. Ejection fraction, what is it, what is normal p 311. Stroke volume— the second factor affecting cardiac output— is never 100% of the volume in the ventricles. Typically, the ventricles eject 60% to 80% of their blood volume. This percentage is called the ejection fraction . An ejection fraction significantly lower than this indicates that the ventricle is weak and may be failing. Cranial nerves. Name, number and what they do. The brain has 12 pairs of cranial nerves Olfactory nerve (I, sensory): Governs sense of smell. Terminates in olfactory bulbs in the cribriform plate, just above the nasal cavity Optic nerve (II, sensory): Concerned with vision. Links the retina to the brain’s visual cortex Oculomotor nerve ((III mainly motor): controls pupil constriction, regulates voluntary movements of the eyelid and eyeball Trochlear nerve (IV mainly motor): regulates voluntary movements of the eyelid and eyeball Trigeminal nerve (V, two sensory and one mixed branch): Sensory branches (ophthalmic and maxillary) sense touch, temp, and pain on the eye, face, and teeth; mixed branch (mandibular) controls chewing and detects sensations in the lower jaw. Ophthalmic branch triggers the corneal reflex: blinking in response to a light touch on the eyeball Abducens nerve (VI mainly motor): regulates voluntary movements of the eyelid and eyeball Facial nerve (VII, mixed): Sensory portion concerned with taste; motor portion controls facial expression and secretion of tears and saliva
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Vestibulocochlear nerve (VIII, sensory): Concerned with hearing and balance Glossopharyngeal nerve (IX, mixed): Motor fibers govern tongue movements, swallowing, and gagging. Sensory fibers handle taste, touch, and temperature from the tongue; also concerned with regulation of blood pressure Vagus nerve (X, mixed): Longest and most widely distributed cranial nerve. Supplies organs in the head and neck as well as those in the thoracic and abd cavities. Plays key role in many heart, lung, digestive, and urinary functions Spinal accessory nerve (XI, mainly motor): Controls movement in the head, neck, and shoulders Hypoglossal nerve (XII, mainly motor): Controls tongue movements 5 main sections of vertebral column Cervical vertebrae (7 vertebrae) Thoracic vertebrae (12 vertebrae) Lumbar vertebrae (5 vertebrae) Sacrum (5 fused vertebrae) Coccyx (4 fused vertebrae) Location/function of parietal, temporal, occipital, frontal lobes, lymph valves, sclera Cerebrum: Largest portion of the brain. Contains Parietal lobe, Frontal lobe, Temporal lobe, Occipital lobe, Insula. Frontal lobe: Central sulcus forms the posterior boundary. Voluntary movements, memory, emotion, social judgment, decision making, reasoning, and aggression; certain aspects of one’s personality Parietal lobe: Central sulcus forms the anterior boundary. Receiving and interpreting bodily sensations; proprioception Occipital lobe: Analyzing and interpreting visual info Temporal lobe: Separated from the parietal lobe by the lateral sulcus. Hearing, smell, learning, memory, emotional behavior, and visual recognition Insula: Hidden behind lateral sulcus. Perception of pain, basic emotions, addiction, motor control, self-awareness, and cognitive functioning Lymph Valves prevent backflow, ensuring that lymph moves steadily away from the tissues and toward the heart. The sclera —formed from dense connective tissue— is the outermost layer of the eye. Most of the sclera is white and opaque; it forms what is called “the white of the eye.” Blood vessels and nerves run throughout the sclera. Location/function of Aldosterone, calcitonin, glomerulus, cell microvilli, cilia, medullary cavity Adrenal cortex – Aldosterone – Targets Kidney - Promotes Na+ retention and K+ excretion, which leads to water retention Calcitonin : Secreted by the cells between the thyroid follicles (parafollicular cells), in response to rising blood calcium levels, calcitonin triggers the deposition of calcium in bone, thus promoting bone formation. The effects of calcitonin are particularly important in children. Has antagonistic effects on PTH.
The first step in the creation of urine from blood plasma occurs in the glomerulus as water and small solutes filter out of the blood and into the surrounding space of Bowman’s capsule. Filtration in the glomerulus occurs for the same reason filtration occurs in other blood capillaries: the existence of a pressure gradient. Bowman’s capsule—also called a glomerular capsule—consists of two layers of epithelial cells that envelop the glomerulus in an open-ended covering. Fluid filters out of the glomerulus and collects in the space between the two layers of Bowman’s capsule. From there, it flows into the proximal renal tubule on the other side of the capsule. Microvilli are folds of the cell membrane that greatly increase the surface area of a cell. Typically found in cells charged with absorbing nutrients—such as the intestines—microvilli can increase a cell’s absorptive area as much as 40 times. Cilia are hair-like processes along the surface of a cell. Unlike microvilli, cilia move. They beat in waves, always in the same direction. They occur primarily in the respiratory tract—where their wave-like motion helps move mucus and foreign particles out of the lungs—and the fallopian tubes—where their motion propels an egg cell or embryo toward the uterus. The central hollow portion of the long bone is called the medullary cavity . Purpose of Vit K , peristalsis, stomach rugae Because the liver synthesizes most of the clotting factors, abnormal liver function interferes with normal blood clotting. Even more interesting is that seemingly mild disorders, such as gallstones, can also interfere with blood clotting. That’s because the synthesis of clotting factors requires vitamin K. Vitamin K is absorbed into the blood from the intestine but, because vitamin K is fat soluble, it can be absorbed only if bile is present. Bile is secreted by the liver. If the bile ducts become blocked, such as by liver disease or gallstones, vitamin K can’t be absorbed and bleeding tendencies develop. Peristalsis: Wave-like muscular contractions that propel food along the digestive tract Rugae: Folds of mucosa and submucosa in the stomach What is osmosis, genetics, heredity, pernicious anemia A type of diffusion, osmosis involves the diffusion of water down the concentration gradient through a selectively permeable membrane. In the body, this often happens when a particular substance can’t cross the membrane. In that situation, the water—not the particles—moves in an effort to equalize the concentration. This process of passing traits from biological parents to children is called heredity , whereas the study of heredity or inheritance is called genetics . Another nutritional anemia—pernicious anemia—results from a lack of vitamin B12. In this instance, the anemia typically occurs because the body can’t assimilate the vitamin because of a lack of a chemical produced in the stomach called intrinsic factor. Regulation of I and O p. 409 To keep the total volume of water in the body in balance, the body uses mechanisms that adjust fluid intake as well as urine output. Various factors, including excessive sweating, cause the volume of total body water to decline. Blood pressure drops, sodium concentration rises, and osmolarity increases.
Mechanisms to increase fluid intake - Physical changes stimulate the thirst center in the hypothalamus - Salivation decreases, causing a dry mouth and the sensation of thirst Consumption of water leads to a rise in total water volume Mechanisms to decrease urine output - Physical changes stimulate the hypothalamus, which, in turn, stimulates the posterior pituitary to secrete antidiuretic hormone (ADH) - ADH prompts the collecting ducts of the kidneys to reabsorb more water and produce less urine - The rate of fluid loss slows until water is ingested When blood volume and pressure are too high, or blood osmolarity is too low, the hypothalamus inhibits the release of ADH. This causes the renal tubules to reabsorb less water, leading to an increased urine output and a decline in total body water. Causes of acidosis/alkalosis p. 418 Causes of Acid Gain (Acidosis) Respiratory : • Retention of CO2 (hypoventilation—such as from emphysema or pneumonia— as well as apnea) Renal/Metabolic : • Increased production of acids (such as ketone bodies in diabetes mellitus or lactic acid in anaerobic metabolism) • Consumption of acidic drugs (such as aspirin) • Inability of the kidneys to excrete H ions • Loss of bicarbonate (such as chronic diarrhea or overuse of laxatives) Causes of Acid Loss (Alkalosis) Respiratory : • Loss of CO2 (hyperventilation) Metabolic : • Loss of gastric juices (such as through vomiting or suctioning) • Excessive ingestion of bicarbonates (such as antacids) High H ion concentration depresses the CNS, which is why acidosis causes symptoms such as disorientation, confusion, and coma. Alkalosis, on the other hand, makes the nervous system more excitable, resulting in symptoms such as tetany and convulsions. Joints-synovial, ball and socket Synovial joints —also called diarthroses —are freely movable. They’re also the most numerous and versatile of all the body’s joints. Not all synovial joints are configured the same. In fact, the body contains six types of synovial joints, with each joint type offering a specific movement. Ball-and-Socket Joint: The ball-shaped head of one bone fits into a cup-like socket of another bone to form this joint to offer the widest range of motion of all joints. The shoulder and hip joints are both ball-and-socket joints. Factors impacting the microbiome Furthermore, when the composition of the microbiome is disrupted, such as by an excess of a specific bacteria or, more often, through the use of broad-spectrum antibiotics, disease can result. Imbalances in the microbiome (called dysbiosis ) are linked to numerous disorders, including diabetes, heart disease, asthma, multiple sclerosis, obesity, inflammatory bowel disease, autism, and even cancer.
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Effect of physical activity on bone Regular exercise may help protect articular cartilage from “wear and tear.” Here’s why: Cartilage depends on synovial fluid for oxygen and nutrients. During exercise, joint compression squeezes fluid and metabolic wastes out of the cartilage. Then, when the weight is removed, the cartilage sucks up synovial fluid like a sponge. The periods of compression and relaxation accompanying exercise cause the synovial fluid, along with its supply of oxygen, nutrients, and phagocytes, to cycle through the cartilage. Without exercise, articular cartilage deteriorates more rapidly because of a lack of nutrition, oxygenation, and waste removal. Warming up before vigorous exercise also helps protect articular cartilage. Once warm, the synovial fluid is less viscous, which allows the cartilage to soak it up more easily. This causes the cartilage to swell, making it a more effective cushion against compression. Regular, moderate exercise can help slow, or even reverse, age-related changes to bones and joints. Regular stretching exercises can improve tendon flexibility, which, in turn, can increase joint range of motion. Because bone adapts to withstand physical stress, exercise can help increase bone density. Likewise, a lack of exercise promotes bone loss. • Exercise: Without adequate physical stress in the form of weight-bearing exercise (which includes walking), bone destruction will outpace bone creation. when an individual participates in weight-bearing exercise, osteocytes trigger the growth of new bone, making bones stronger. This makes any weight-bearing exercise, especially lifting weights, ideal for those at risk for osteoporosis SA node, DNA, cortisol, glucagon, thyroxine, GH, insulin, ADH- location function The SA node is the heart’s primary pacemaker DNA—the largest molecule in the body—carries the genetic code for every hereditary characteristic ranging from eye color to nose shape. The DNA (deoxyribonucleic acid) molecule—a type of nucleic acid —is one of the largest and most complex of all molecules. More importantly, DNA stores all of a cell’s genetic information—information it needs to develop, function, and maintain itself. Adrenal Cortex – Cortisol – Targets most tissues - Stimulates the breakdown of fat and protein and the conversion of fat and protein to glucose; enhances tissue repair; anti-inflammatory; in large amounts, inhibits the immune system Alpha cells secrete the hormone glucagon . Between meals, when blood glucose levels fall, glucagon stimulates liver cells to convert glycogen into glucose and also to convert fatty acids and amino acids into glucose (gluconeogenesis). Thyroxine – Thyroid hormone - > rate of metabolism Growth hormone (GH) , or somatotropin , acts on the entire body to promote protein synthesis, lipid and carbohydrate metabolism, and bone and skeletal muscle growth. Beta cells secrete the hormone insulin . After eating, the levels of glucose and amino acids in the blood rise. Insulin stimulates cells to absorb both of these nutrients, causing blood glucose levels to fall.
Antidiuretic hormone (ADH) : Secreted by the posterior pituitary gland (neurohypophysis), ADH causes the cells of the collecting duct to become more permeable to water. Water flows out of the tubule and into capillaries, causing urine volume to fall and blood volume to increase. Reabsorbs H2O Increased Blood volume Increased BP Inner ear structures, location, function, cochlea Semicircular canals : These structures are crucial for the maintenance of equilibrium and balance. Vestibule : This structure, which marks the entrance to the labyrinths, contains organs necessary for the sense of balance. Cochlea : This snail-like structure contains the structures for hearing. The spirals of the cochlea are divided into three compartments. The middle compartment is a triangular duct (called the cochlear duct) filled with endolymph; the outer two compartments are filled with perilymph. Layers of the skin, purpose of integument, structures contained in the dermis The skin, also called the cutaneous membrane, consists of two layers: the epidermis and the dermis. More than just a covering for the body, skin is crucial for human survival. Perhaps its most obvious task is to define the body’s structure: joining forces with the muscular and skeletal systems to build the body’s framework. But that’s just one small part of the skin’s role. This thin, self-regenerating tissue also separates the internal from the external environment, protects the body from invasion by harmful substances, and helps maintain homeostasis. In addition, sensory nerve receptors in the skin gather information about the outside world while its flexibility and ability to stretch permit freedom of movement. Last but not least, changes in the skin can signal diseases or disorders in other body systems. The dermis—the inner, deeper layer—is composed of connective tissue. It contains primarily collagen fibers (which strengthen the tissue), but it also contains elastin fibers (which provide elasticity) and reticular fibers (which bind the collagen and elastin fibers together). The dermis contains an abundance of blood vessels in addition to sweat glands, sebaceous glands, and nerve endings. Hair follicles are also embedded in the dermis. Finger-like projections, called papillae, extend upward from the dermis. These projections interlock with downward waves on the bottom of the epidermis, effectively binding the two structures together. brain ventricles contain what fluid A clear, colorless fluid called cerebrospinal fluid (CSF) fills the ventricles and central canal; it also bathes the outside of the brain and spinal cord. CSF is formed from blood by the choroid plexus (a network of blood vessels lining the floor or wall of each ventricle). main bones of upper/lower arm and leg. Medullary cavity, what is in it. The upper limb, or arm, consists of the humerus (upper arm bone), the radius and the ulna (the bones of the lower arm), and the carpals (the bones of the hand).
The bones of the lower limb—which consist of the femur (thigh bone), patella (kneecap), tibia and fibula (bones of the lower leg), and foot—join with the pelvis to give the body a stable base. The inside of the medullary cavity is lined with a thin epithelial membrane called the endosteum . • In children, the medullary cavity is filled with blood cell-producing red bone marrow . In adults, most of this marrow has turned to yellow marrow , which is rich in fat. Phases of digestion-mechanical, chemical, absorption etc.-where do these occur Mechanical digestion : This is the first phase of digestion. It involves physically breaking down food into smaller pieces, beginning with chewing in the mouth and continuing with contractions and churning in the stomach and small intestine. Chemical digestion : The second phase of digestion uses digestive enzymes produced in the salivary glands, stomach, pancreas, and small intestines to break down food particles into nutrients (such as glucose, amino acids, and fatty acids) that cells can use. Small intestine : Most chemical digestion, and most nutrient absorption, occurs in the small intestine. WBC, action and function-neutrophils/basophils/eosinophils/lymphocytes Neutrophils Most abundant of the WBCs, neutrophils make up 60% to 70% of all the WBCs in circulation. The nucleus of young neutrophils looks like a band or a stab wound; therefore, they are sometimes called band cells or stab cells. They are also called polymorphonuclear leukocytes (PMNs) because the shape of the nucleus varies between neutrophils. Highly mobile, neutrophils quickly migrate out of blood vessels and into tissue spaces, where they engulf and digest foreign materials. Worn-out neutrophils left at the site of infection form the main component of pus. Eosinophils Eosinophils account for 2% to 5% of circulating WBCs. Although few exist in the bloodstream, eosinophils are numerous in the lining of the respiratory and digestive tracts. Eosinophils are involved in allergic reactions; they also kill parasites. Basophils The fewest of the WBCs, basophils comprise only 0.5% to 1% of the WBC count. Basophils possess little or no phagocytic ability. Basophils secrete heparin, which prevents clotting in the infected area so WBCs can enter; they also secrete histamine, a substance that causes blood vessels to leak, which attracts WBCs. All granulocytes circulate for 5 to 8 hours and then migrate into the tissues, where they live another 4 or 5 days Lymphocytes The second most numerous of the WBCs, lymphocytes constitute 25% to 33% of the WBC count. Lymphocytes are the smallest of the WBCs. Lymphocytes are responsible for long-term immunity. There
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are two types: *T lymphocytes, which directly attack an infected or cancerous cell *B lymphocytes, which produce antibodies against specific antigens All lymphocytes begin in the bone marrow; whereas some mature there, others migrate to the thymus to finish developing. After maturing, all lymphocytes colonize the organs and tissues of the lymph system. Afterward, they continually cycle between the bloodstream and lymph system. Lymphocytes may survive from a few weeks to decades. Monocytes Monocytes comprise 3% to 8% of the WBC count. Monocytes are the largest of the WBCs. Monocytes are highly phagocytic and can engulf large bacteria and viral-infected cells. After circulating in the bloodstream for 10 to 20 hours, monocytes migrate into tissues, where they transform into macrophages: aggressive phagocytic cells that ingest bacteria, cellular debris, and cancerous cells. Macrophages can live as long as a few years. Resp anatomy-trachea/bronchi/bronchioles/alveoli, location/function The lower respiratory tract consists of the trachea, bronchi, and lungs. The trachea and the bronchi distribute air to the interior of the lungs; deep within the lungs is where gas exchange occurs. The trachea and two bronchi with their many branches, resemble an inverted tree; that’s why it’s often called the bronchial tree. The trachea lies in front of the esophagus; it is a rigid tube about 4.5 inches (12 cm) long and 1 inch (2.5 cm) wide. C-shaped rings of cartilage encircle the trachea to reinforce it and keep it from collapsing. The open part of the “C” faces posteriorly, giving the esophagus room to expand during swallowing. At the carina, the trachea branches into two primary bronchi, which are also supported by C- shaped rings of cartilage. The right bronchus is slightly wider and more vertical than the left, making this the most likely location for aspirated food particles and small objects to lodge. Immediately after entering the lungs, the primary bronchi branch into secondary bronchi: one for each of the lung’s lobe (two on the left and three on the right). Secondary bronchi branch into smaller tertiary bronchi. The cartilaginous rings surrounding the bronchi become irregular and disappear in the smaller bronchioles. Tertiary bronchi continue to branch, resulting in very small airways called bronchioles. Bronchioles divide further to form thin-walled passages called alveolar ducts. Alveolar ducts throughout the lungs terminate in clusters of alveoli called alveolar sacs, these are the primary structures for gas exchange. A layer of protective mucus coats the lining of the bronchial tree, which helps purify air entering the respiratory tract. This cleansing mucus moves up from the lower bronchial tree toward the pharynx, propelled by millions of hair-like cilia that line the respiratory mucosa. The cilia beat in one direction—upward—so that mucus will move toward the pharynx.
The lung passages all exist to serve the alveoli, because it’s within the alveoli that gas exchange occurs. Deoxygenated blood flows into alveoli through pulmonary arterioles, and oxygenated blood leaves alveoli via pulmonary venules. Alveoli are separated from one another by a thin layer of tissue. A mesh of pulmonary capillaries encases each alveolus. The extremely thin walls of the alveoli, and the closeness of the capillaries, allow for efficient gas exchange. Elastic fibers give alveoli the ability to expand during inhalation and spring back into shape during exhalation. During inspiration, air flows into the alveoli, inflating them like tiny balloons. The ability of alveoli to expand as they fill with air and recoil as they expel air depends on their own elasticity as well as the compliance of surrounding lung tissue. If lung tissue is stiff and non-compliant, it resists the alveoli as they try to expand, limiting their ability to do so. If lung tissue is stiff and non-compliant, it resists the alveoli as they try to expand, limiting their ability to do so. Once alveoli fill with air, oxygen crosses the respiratory membrane—which consists of the alveolar epithelium, the capillary endothelium, and their joined basement membranes—and moves into red blood cells in surrounding capillaries. As red blood cells take up oxygen, they release carbon dioxide, which then passes into the alveoli. Alveoli deflate during expiration, expelling their content of carbon dioxide, which travels back up the conducting airways to be expelled by the lungs. location/function skeletal, smooth muscle, voluntary/involuntary muscles, acrosome Cardiac: Found only in the heart. Consists of short, branching fibers that fit together at intercalated discs Striated Involuntary Smooth: Found in the digestive tract, blood vessels, bladder, airways, and uterus Nonstriated Involuntary Skeletal: Attached to bone and causes movement of the body Striated Voluntary Acrosome: Topping the head of the sperm is a cap called an acrosome . The acrosome contains enzymes that help the sperm penetrate the egg during fertilization. Factors that increase/decrease BP Three Factors That Affect Blood Pressure How Factors Affect Blood Pressure Cardiac output : When the heart beats harder, such as during exercise, cardiac output increases. When cardiac output increases, blood pressure increases. When cardiac output falls, such as when exercise ends or the heart is weak, blood pressure falls. ↑CO = ↑BP ↓CO = ↓BP
Blood volume : When blood volume declines, such as from dehydration or a hemorrhage, blood pressure falls. To try and preserve blood pressure, the kidneys reduce urine output, which helps boost blood volume and raise blood pressure. ↓Volume = ↓BP ↑Volume = ↑BP Resistance : Also called peripheral resistance, this is the opposition to flow resulting from the friction of moving blood against the vessel walls. The greater the resistance, the slower the flow and the higher the pressure. The lower the resistance, the faster the flow and the lower the pressure. ↑Resistance = ↓Flow and ↑Pressure ↓Resistance = ↑Flow and ↓Pressure Causes of metabolic acidosis/alkalosis p 418 read this box carefully. Causes of Acid Gain (Acidosis) Respiratory : • Retention of CO2 (hypoventilation—such as from emphysema or pneumonia— as well as apnea) Renal/Metabolic : • Increased production of acids (such as ketone bodies in diabetes mellitus or lactic acid in anaerobic metabolism) • Consumption of acidic drugs (such as aspirin) • Inability of the kidneys to excrete H ions • Loss of bicarbonate (such as chronic diarrhea or overuse of laxatives) Causes of Acid Loss (Alkalosis) Respiratory : • Loss of CO2 (hyperventilation) Metabolic : • Loss of gastric juices (such as through vomiting or suctioning) • Excessive ingestion of bicarbonates (such as antacids) High H ion concentration depresses the CNS, which is why acidosis causes symptoms such as disorientation, confusion, and coma. Alkalosis, on the other hand, makes the nervous system more excitable, resulting in symptoms such as tetany and convulsions. Know the difference between respiratory/ metabolic acidosis and alkalosis See above Dehydration and aging p 419 purple box. Elderly adults tend not to feel thirsty and therefore fail to drink enough water, even when they are becoming dehydrated because of low water intake or excess fluid loss from hot conditions. At the same time, aging kidneys have a reduced capacity to conserve fluid. As a result, elderly individuals have a higher risk of dehydration. Total body water also decreases with age. In a young adult man of ideal body weight, total body water may comprise 60% to 65% of his body mass. By age 80 years, total body water may drop to 50%. In addition, aging kidneys are less effective at reabsorbing sodium, leading to excess urination, volume depletion, and hyponatremia. The secretion of hydrogen ions is also impaired, increasing the elderly patient’s risk for developing metabolic acidosis. What sperm/egg chromosomes are needed to produce male/female offspring
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23; XX female, XY male Process of spermatogenesis, how long do they live in female repro tract, where does fertilization occur Sperm begin as spermatogonia, primitive sex cells with 46 chromosomes located in the walls of the seminiferous tubules. Spermatogonia divide by mitosis to produce two daughter cells, each with 46 chromosomes. These cells then differentiate into slightly larger cells called primary spermatocytes, which move toward the lumen of the seminiferous tubule. Through meiosis, the primary spermatocyte yields two genetically unique secondary spermatocytes, each with 23 chromosomes. Each secondary spermatocyte divides again to form two spermatids. Spermatids differentiate to form heads and tails and eventually transform into mature spermatozoa (sperm), each with 23 chromosomes. Sperm can remain viable within the female reproductive tract for as long as six days. On the other hand, the egg is only viable for 24 hours. Because it takes 72 hours for the egg to reach the uterus, fertilization typically occurs in the distal third of the fallopian tube. Semen-function, how it’s made, qualities that aid fertilization Emitted during the ejaculation that accompanies orgasm, semen is a whitish fluid containing both sperm and the fluid secretions of the accessory glands. About 65% of the fluid volume of semen comes from the seminal vesicles, about 30% comes from the prostate gland, and about 5% comes from the bulbourethral gland. Each ejaculation expels between 2 and 5 ml of semen containing between 40 and 100 million sperm. Two key qualities of semen include its stickiness and its alkalinity. Immediately after ejaculation, semen becomes sticky and jelly-like. This characteristic promotes fertilization by allowing the semen to stick to the walls of the vagina and cervix instead of immediately draining out. The alkalinity of semen counteracts the acidity of the vagina ; this is important because sperm become immobile in an acidic environment. Primary sex organs-male/female, male external sex organs Primary sex organs • Primary sex organs are called gonads; they include: • testes in males • ovaries in females The gonads produce sex cells (gametes); these include: • sperm in males • eggs (ova) in females The external organs include the penis, scrotum and testicles. Good luck and finish strong! Almost there. You can do this!
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Acidosis: A decrease in the pH of the blood as a result of an accumulation of acids; may result from respiratory or metabolic disturbances Alkalosis: An increase in the pH of the blood as a result of a loss of acid; may result from respiratory or metabolic disturbances Anion: Ion with a negative charge Buffers: Mechanisms employed by the body to keep acids and bases in balance Cation: Ion with a positive charge Chemical buffers: Use a chemical to bind H_ and remove it from solution when levels are too high and to release H_ when levels fall; include the bicarbonate buffer system, the phosphate buffer system, and the protein buffer system Dehydration: A fluid deficiency resulting from the loss of more water than sodium Edema: Accumulation of fluid in interstitial spaces Electrolytes: Substances that break up into electrically charged particles called ions when dissolved in water Extracellular fluid: Body fluid residing outside of cells Hypercalcemia: An excessive concentration of calcium in the blood Hyperkalemia: An excessive concentration of potassium in the blood Hypernatremia: An excessive concentration of sodium in the blood Hypocalcemia: Abnormally low blood calcium Hypokalemia: Abnormally low blood potassium Hyponatremia: Abnormally low blood sodium Hypovolemia: Decreased blood volume Interstitial fluid: Fluid residing between cells inside tissues; a component of extracellular fluid Intracellular fluid: Body fluid residing inside of cells Physiological buffers: Use the respiratory and urinary systems to alter the output of acids, bases, or CO2 to stabilize pH Transcellular fluid: Miscellaneous extracellular fluid that includes cerebrospinal fluid, synovial fluid in the joints, vitreous and aqueous humors of the eye, and digestive secretions Turgor: Elasticity of the skin Volume depletion: Results from blood loss or when both sodium and water is lost, such as from diarrhea Water intoxication: May occur when someone consumes an excessive amount of water or when someone replaces heavy losses of water and sodium with just water Acrosome: Cap topping the head of the sperm that contains enzymes to facilitate penetration of the egg Ampulla: Middle portion of the fallopian tube Areola: Pigmented area encircling the nipple of the breast Bartholin’s glands: Two pea-sized glands on either side of vaginal opening that secrete a fluid to lubricate the vulva Bulbourethral glands: Pea-sized gland that secrets a clear fluid into penile portion of urethra during sexual arousal Cervix: Inferior end of the uterus Clitoris: Small mound of erectile tissue in female external genitalia Contraception: Any method used to prevent pregnancy
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Corpus albicans: Inactive scar tissue that results when the corpus luteum degenerates Corpus cavernosa: Two large cylinders of tissue within the shaft of the penis Corpus luteum: Remnants of the ovarian follicle after ovulation that secretes large amounts of progesterone and small amounts of estrogen Corpus spongiosum: Small cylinder of tissue encircling the urethra in the shaft of the penis Cremaster muscle: Muscle surrounding spermatic cord and testes Endometrium: Vascular mucous membrane lining the uterus; thickens each cycle in anticipation of receiving a fertilized egg Epididymis: Convoluted tube resting on the side of the testes in which sperm mature Estrogen: Hormone secreted by the ovaries that is responsible for stimulating development of female secondary sex characteristics; it also plays a role in triggering ovulation Fallopian tubes: Tubes extending from near the ovary to the uterus Fimbriae: Finger-like projections at the ends of the fallopian tubes Follicular phase: Portion of the ovarian cycle during which several follicles in the ovary resume development Fornices: Pockets formed by extension of the vagina beyond the cervix Fundus: Upper portion of the uterus Gametes: Sex cells, which include the sperm in males and eggs in females Glans penis: Slightly bulging head of the penis Gonad: Primary sex organs; includes the testes in males and the ovaries in females Graafian follicle: A mature follicle of the ovary Hymen: Fold of mucous membrane that partially covers the entrance to the vagina Infundibulum: Funnel-shaped, distal end of the fallopian tube Isthmus: Portion of the fallopian tube closest to the uterus Labium majus: One of two thick folds of skin and adipose tissue forming female external genitalia Labium minus: One of two thinner, hairless folds of skin just inside labium majus in female external genitalia Leydig cells: Cells lying between seminiferous tubules that produce testosterone Luteal phase: Portion of the ovarian cycle occurring after ovulation and before menstruation Meiosis: Process of cell division producing cells (eggs or sperm) that contain half the number of chromosomes found in somatic cells Menarche: First menstrual period Menopause: The period that marks the permanent cessation of menstruation Menstrual cycle: Part of the reproductive cycle that focuses on changes in the uterus Menstruation: Cyclical shedding of uterine endometrium Mons pubis: Mound of haircovered adipose tissue overlying the symphysis pubis Myometrium: Smooth muscle layer of the uterus; contracts during delivery Oocyte: Immature egg Oogenesis: Process whereby a mature ovum is formed Ovarian cycle: Part of the reproductive cycle that centers on changes in the ovaries Ovarian follicle: Oocyte and surrounding follicular cells Perimetrium: Outer serous layer of uterine wall Prepuce: Foreskin of penis
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Prostate gland: Gland that surrounds the neck of the bladder and urethra in males; secretes alkaline fluid that forms part of semen Rete testis: Network of vessels leading away from the seminiferous tubules Scrotum: Sac of tissue surrounding the testes Semen: Whitish fluid containing sperm emitted during ejaculation Seminal vesicle: Gland opening into the vas deferens that secretes many components of semen Seminiferous tubules: Tiny ducts in the testes in which sperm are produced Sertoli cells: Cells contained in the wall of seminiferous tubules that promote the development of sperm by supplying nutrients, removing waste, and secreting hormone inhibin Spermatogenesis: Sperm formation that takes place in the seminiferous tubules of the testicles Testes: Male organs that manufacture sperm and produce the male hormone testosterone Testosterone: Primary male sex hormone; secreted by the testes Uterus: Muscular chamber that houses and nurtures a growing embryo and fetus Vas deferens: Tube that carries sperm out of the epididymis to the ejaculatory duct Vestibule: Area inside the labia containing urethral and vaginal openings Afterbirth: Final stage of delivery which involves expulsion of placenta, amnion, and other fetal membranes Allantois: Fetal membrane that serves as the foundation for the developing umbilical cord Amnion: Transparent sac enveloping the embryo and fetus; fills with amniotic fluid Blastocyst: Cell cluster (forming at the end of preembryonic development) that implants in the endometrium Blastomere: Cell formed by division of fertilized ovum Braxton-Hicks contractions: Weak, irregular contractions that normally occur late in pregnancy Chorion: Outermost fetal membrane that develops projections (chorionic villi) that penetrate the uterus Cleavage: Process by which the fertilized egg divides by mitosis Colostrum: Thin, yellowish fluid rich in protein and immunoglobulins secreted by the mother’s breast for the first few days after delivery Crowning: First appearance of the top of the baby’s head during birth process Ductus arteriosus: Shunt existing between the pulmonary artery and descending aorta that is present during fetal development Ductus venosus: Shunt bypassing the fetal liver that is present during fetal development Ectoderm: The outer germ layer in a developing embryo Effacement: Progressive thinning of cervical walls during first stage of labor Embryo: Stage of development beginning 16 days after conception and lasting until the eighth week Embryonic stage: Stage of prenatal development beginning after the sixteenth day and lasting until the eighth month Endoderm: Innermost of the three germ layers in a developing embryo Episiotomy: Surgical incision made between vagina and anus to enlarge vaginal opening during birth process Fertilization: The union of an egg and a sperm, which is the beginning of human development
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Fetal stage: Stage of prenatal development beginning the eighth week and lasting until birth Fetus: Unborn human baby from eight weeks following conception until birth Foramen ovale: Opening between the right and left atria present during fetal development; normally closes shortly after birth Gestation: Length of time from conception until birth Human chorionic gonadotropin (HCG): Hormone secreted during the early part of pregnancy that prompts the corpus luteum to secrete estrogen and progesterone; forms the basis for most pregnancy tests Lactation: The process whereby the mammary glands secrete milk Lanugo: Fine hair covering fetus Mesoderm: The middle germ layer in a developing embryo Morula: Cluster of 16 cells resulting from cleavage of an ovum Multipara: Woman who has previously given birth Neonate: Newborn child Parturition: Process of giving birth Placenta: Pancake-shaped accessory organ that supplies the fetus with oxygen and nutrients and also secretes the hormones necessary to maintain the pregnancy Preembryonic: Stage of prenatal development beginning at fertilization and lasting for 16 days Prenatal: Period before birth Primipara: Woman giving birth for the first time Quickening: Fetal movement Senescence: Process of degeneration Surfactant: Lipid and protein mixture that reduces alveolar surface tension in the lungs Trophoblast: Outermost layer of the developing blastocyst Umbilical cord: Cord containing two arteries and one vein that attach the developing fetus to the placenta Vernix caseosa: White cheese-like substance covering fetus Yolk sac: Membranous sac that produces red blood cells during the embryonic stage Zona pellucida: Gel-like membrane surrounding the ovum Zygote: A fertilized egg Allele: Alternative form of a gene Autosomes: Nonsex chromosomes Carrier: Someone who carries a normal gene along with its recessive allele Chromosome: Long strand of DNA found in the cell’s nucleus Disjunction: Process by which homologous chromosomes separate during meiosis to produce two daughter cells Genes: Segments of DNA that contain the traits each person inherits Genetics: The study of heredity or inheritance Genome: A complete set of genetic information for one person Genotype: The genetic information stored at the locus of a gene, even if those traits are not expressed Heredity: The passing of traits from biological parents to children Heterozygous: Possessing different alleles at a given locus Homologous: Similar in structure, such as two similar chromosomes that are paired together
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Homozygous: Possessing similar alleles at a given locus Karyotype: A chart showing all the chromosomes arranged in order by size and structure Locus: The location of a specific gene on a chromosome Monosomy: Condition in which a daughter cells has one chromosome with no mate Multifactorial disorder: Disorder resulting from many contributing factors, including genetic and environmental Mutation: A permanent change in genetic material Nondisjunction: When a pair of chromosomes fails to separate during meiosis and two chromosomes go to the same daughter cell Nondisjunction: When chromosomes fail to separate during meiosis Phenotype: The detectable, outward manifestation of a genotype Polygenic inheritance: Phenomenon whereby genes at two or more loci contribute to the expression of a single trait Sex chromosomes: Chromosomes designated by the letters X and Y that determine gender Trisomy: Condition in which a daughter cells contains three of a particular chromosome
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