BIO201 Lab 5

pdf

School

West Coast University *

*We aren’t endorsed by this school

Course

201

Subject

Biology

Date

Jan 9, 2024

Type

pdf

Pages

Uploaded by ChiefKnowledge11777

Lab 5 Tissues and Skin BIO201L Student Name: Ani Harutyunyan Access Code (located on the lid of your lab kit): AC-BX89CU Lab Report Format Expecta0ons U"lize college level grammar and professional forma4ng when comple"ng this worksheet. Submissions without proper forma4ng, all required photos or suﬃcient responses will be rejected. Pre-lab Ques>ons 1. What is a (ssue? Tissue is composed of similar cells working together to perform parBcular tasks in the body. The 4 primary categories are epithelial, connecBve, muscle, and nervous Bssue and each type plays a role in the structure and operaBon of organs and enBre body systems. 2. What is the func(on of epithelial (ssue? Epithelial Bssue covers and lines body surfaces, performing protecBve, absorpBve, secretory, excretory, and sensory funcBons. 3. What is the func(on of connec(ve (ssue? ConnecBve Bssue supports, binds, and protects structures in the body, facilitates transportaBon of substances, stores energy, and helps in immune responses. 4. What is the func(on of muscular (ssue? Muscular Bssue is responsible for producing movement, maintaining posture, and generaBng heat through contracBon. 5. What is the func(on of nervous (ssue? Nervous Bssue coordinates and controls body acBviBes by transmiNng electrical impulses throughout the body. 6. Describe sebaceous glands, sweat glands, and hairs with regard to the func(on of the skin. Sebaceous glands, sweat glands, and hairs each play a disBnct role in the funcBon of the skin: Sebaceous glands: They secrete sebum to moisturize and protect the skin.

Lab 5 Tissues and Skin BIO201L Sweat glands: Eccrine glands regulate temperature through sweat evaporaBon, while apocrine glands, acBve from puberty, play a role in body odor. Hairs: They provide a protecBve barrier, thermal insulaBon, and sensory input via hair follicles. Together, sebaceous glands, sweat glands, and hairs contribute to the protecBve, regulatory, and sensory funcBons of the skin, which include maintaining homeostasis, protecBng against environmental hazards, and allowing for sensaBon. 7. What is the func(on of melanin? Melanin is a pigment that protects the skin from UV radiaBon and contributes to its color. 8. List the similari(es and differences of the layers of the epidermis. similariBes: - Every layer belongs to the epidermis and shares the primary role of bodily defense. - They are all primarily composed of keraBnocytes at various levels of development. - The layers collecBvely uphold the skin's protecBve barrier. Differences: -Stratum Basale: Deepest, with acBvely dividing cells and melanocytes. -Stratum Spinosum: Several layers thick, with cells developing intercellular spiny projecBons. -Stratum Granulosum: Cells accumulate keraBn, begin to lose nuclei, iniBaBng cell death. -Stratum Lucidum: Present only in thick skin, with dead, ﬂa]ened, translucent cells. -Stratum Corneum: Outermost, with layers of dead cells filled with keraBn, providing barrier protecBon.

Lab 5 Tissues and Skin BIO201L EXPERIMENT 1: OBSERVATION OF MITOSIS IN A PLANT CELL Introduc>on Ques>ons 1. What is the difference between simple, stra(fied and pseudostra(fied epithelial (ssue? Simple epithelial Bssue is a single layer of cells for absorpBon and filtraBon, straBfied epithelium consists of mulBple cell layers for protecBon, and pseudostraBfied Bssue, while appearing layered due to uneven nuclei, actually has all cells touching the basement membrane and is typically ciliated for secreBon and movement of mucus. 2. What is the difference between mul(polar, bipolar and unipolar neurons? MulBpolar neurons have mulBple extensions for complex connecBons in the CNS, bipolar neurons have two extensions for specific sensory pathways, and unipolar neurons have a single process that branches to relay sensory informaBon to the spinal cord. Does the number of cell layers or the cell shape play a role in the func(on of the epithelial (ssue? Provide three examples. Certainly, the funcBonality of epithelial Bssues is significantly inﬂuenced by their cellular arrangement and shape, as demonstrated by these instances: Simple Squamous Epithelium: - Composed of a single layer of thin cells. - Role: Enables quick diffusion and filtering. - LocaBon: Found in lung alveoli for eﬃcient gas exchange and within blood vessel linings for effecBve transfer of substances. StraBfied Squamous Epithelium: - Consists of several layers of ﬂa]ened cells. - Role: Offers protecBon against physical damage and microbial intrusion. - LocaBon: Present in the outer layer of the skin, safeguarding against external damage and infecBon. Simple Columnar Epithelium: - A single layer of tall, pillar-like cells. - Role: Specialized in absorbing nutrients and releasing digesBve enzymes. - LocaBon: Lines the stomach and intesBnal walls, aiding in digesBon and nutrient uptake.

Your preview ends here

Eager to read complete document? Join bartleby learn and gain access to the full version

Access to all documents
Unlimited textbook solutions
24/7 expert homework help

Lab 5 Tissues and Skin BIO201L The design of these epithelial Bssues is tailored to meet specific funcBonal needs in various parts of the body.

Lab 5 Tissues and Skin BIO201L Data and Observa>ons 1. Iden(fy the following (ssue slides . ( Hint : Use the given (ssue types to find them within the online database.) ” A. Simple Squamous Epithelium B. Simple Cuboidal Epithelium C. Adipose ConnecBve Tissue D. ReBcular ConnecBve Tissue E. ElasBc CarBlage ConnecBve Tissue F. Cardiac Muscle Tissue G. Skeletal Muscle Tissue H. ReBcular ConnecBve Tissue A) Epithelial Tissue B) Epithelial Tissue C) Connec5ve Tissue D) Connec5ve Tissue E) Connec5ve Tissue F) Muscular Tissue G) Muscular Tissue H) Uniden5fied Tissue

Lab 5 Tissues and Skin BIO201L Results and Discussion 1. Describe the cell shape of squamous, cuboidal and columnar epithelial cells. Squamous cells are ﬂat for diffusion, cuboidal cells are cube-shaped for secreBon and absorpBon, and columnar cells are tall for protecBon and specialized funcBons. List and describe the different types of connec(ve (ssue. What similari(es and differences did you no(ce when viewing the prepared slides? Adipose Tissue - Close-knit fat cells at low magnificaBon, with detailed cellular structures visible at high magnificaBon. Areolar ConnecBve Tissue - Tan with speckled fibroblasts; resembles the moon's surface under high magnificaBon. ReBcular ConnecBve Tissue - Yellow-orange with a crystal-like appearance at low power; detailed fibrous branches at high power. Dense Regular ConnecBve Tissue- Appears as a stream of red collagen fibers and cells at low power, with idenBfiable fibroblast nuclei at high power. Dense Irregular ConnecBve Tissue - ChaoBc arrangement of fibers and cells at low power, detailed collagen network at high power. Hyaline CarBlage- Follicle-like structure with a dense outer layer and central cells in lacunae at low power. ElasBc CarBlage- Scaly texture at low power, with a thick outer layer and visible cells and lacunae at high power. FibrocarBlage - Cells appear as holes at low power, with a textured, mountain-like structure at high power. 2. What are the three components of the extracellular matrix in connec(ve (ssue? It’s composed of a supporBve ground substance, strengthening fibers, and specialized cells. 3. What are the three types of car(lage? What are their similari(es and differences? The 3 types of carBlages are hyaline, fibrocarBlage, and elasBc. All three types of carBlage contain chondrocytes and are avascular, but hyaline is moderately supporBve and ﬂexible, fibrocarBlage is tough and resistant to pressure, while elasBc carBlage is highly ﬂexible. 4. What are the three types of muscular (ssue? For each, describe the cell shape, the type of control (voluntary or involuntary) and the presence or absence of stria(ons. Skeletal Muscle: Long, striated fibers, mulBple nuclei, voluntary control. Cardiac Muscle: Branched, striated fibers with intercalated discs, single nucleus, involuntary control.

Your preview ends here

Eager to read complete document? Join bartleby learn and gain access to the full version

Access to all documents
Unlimited textbook solutions
24/7 expert homework help

Lab 5 Tissues and Skin BIO201L Smooth Muscle: Spindle-shaped, non-striated fibers, single nucleus, involuntary control. 5. Looking at the nervous (ssue, state the cell processes visible (i.e., axon) on the prepared slide. For each process, state the func(on. 1. Axons: Relay signals from the neuron body outward. 2. Dendrites: Gather incoming signals toward the neuron body. 3. Synapses: JuncBons where neurons exchange informaBon. 4. Axon Hillock: Launches electrical impulses down the axon.

Lab 5 Tissues and Skin BIO201L EXPERIMENT 2: MICROSCOPIC SLIDE EXAMINATION - SKIN Introduc>on Ques>ons 1. List the five layers of the epidermis from most internal to most external and describe their func(on. Stratum Basale (Basal Layer): -FuncBon: foundaBon layer; where new skin cells are generated and is the site of melanin (the pigment in skin) producBon. Stratum Spinosum (Spiny Layer): - FuncBon: lends skin its strength and suppleness, with cells starBng to produce the protein keraBn. Stratum Granulosum (Granular Layer): - FuncBon: skin cells conBnue to ﬂa]en and pack with keraBn, beginning the process of cell death. Stratum Lucidum (Clear Layer): - FuncBon: Found only in the thick skin of the hands and feet, it adds an addiBonal defense layer. Stratum Corneum (Horny Layer): - FuncBon: Comprising several layers of dead, ﬂat cells, it forms the tough outer shell of the skin, offering protecBon from external elements. 2. List the two layers of the dermis from most internal to most external and describe their func(on. ReBcular Layer: The thicker, deep layer providing skin with strength and resilience due to dense connecBve Bssue. Papillary Layer: The outer layer closest to the epidermis, nourishing it and creaBng fingerprints with its projecBons. Data and Observa>ons 1. Label the arrows in the following slide image: A. Epidermis Layer

Lab 5 Tissues and Skin BIO201L B. sweat gland duct C. dermal papillae D. dermis layer E.

Your preview ends here

Eager to read complete document? Join bartleby learn and gain access to the full version

Access to all documents
Unlimited textbook solutions
24/7 expert homework help

Lab 5 Tissues and Skin BIO201L Results and Discussion 1. Determine whether the following statements pertain to the epidermis or dermis. ” Statement Epidermis or Dermis This layer consists of the papillary layer and the re(cular layer. Dermis Composed of kera(nized stra(fied Squamous epithelium. Epidermis Langerhans cell and Merkel cell reside in this layer. Epidermis Composed of dense irregular connec(ve (ssue. Dermis The fingerprint paRern, unique to each individual, is created in this layer. Dermis Outermost layer of skin. Epidermis This layer has laminated granules and keratohyalin granules within the stratum granulosum. Epidermis The dense supply of blood allows this layer to play a part in body temperature regula(on. Dermis

Lab 5 Tissues and Skin BIO201L EXPERIMENT 3: OBSERVATION OF MITOSIS IN A PLANT CELL Introduc>on Ques>ons 1. What is the purpose of sweat glands? Why do they produce sweat? Sweat glands regulate body temperature by producing sweat, which cools the body as it evaporates from the skin, keeping a stable internal body temperature. 2. How does sweat achieve its intended purpose? Sweat evaporaBng from the skin draws heat away, thereby reducing body temperature and providing a cooling effect. Data and Observa>ons Record your observa(ons from the experiment below in Table 2. Table 2: Sweat Gland Distribu5on Results and Discussion 1. What area of the body had the greatest density of sweat glands, based on your experimental results? What area had the lowest? Why do you think this is? Sweat emi]ed onto the skin absorbs body heat, and upon evaporaBon, it releases this heat into the atmosphere, lowering the body's temperature and providing a cooling effect, a crucial mechanism for body temperature regulaBon in hot condiBons or during exercise. Body Region Sweat Glands/cm 2 Right Anterior Forearm 45 Right Palm 60 Right Anterior Thigh 30 Right Anterior Foot 42

Lab 5 Tissues and Skin BIO201L EXPERIMENT 4: SKIN RECEPTORS Introduc>on Ques>ons 1. Certain areas of the body will have a greater concentra(on of skin receptors. Formulate a hypothesis that aims to predict where you will find the highest and lowest density of receptors. Use what you know about skin receptors to provide reasoning that backs up your hypothesis. Hypothesis: The highest density of skin receptors will be found in areas of the body that require the most tacBle sensiBvity and fine motor control, such as the fingerBps, lips, and face. Conversely, the lowest density of receptors will likely be found in areas with less need for such sensiBvity, like the back or the soles of the feet. Reasoning: The density of skin receptors, especially mechanoreceptors involved in touch and propriocepBon, is greater in areas requiring fine sensory discriminaBon and complex tasks, such as the fingerBps and face. This allows for precise acBons and social interacBons. Body parts less involved in such detailed funcBons, like the back, have fewer receptors, correlaBng with their minimal need for tacBle sensiBvity. Data and Observa>ons Record your caliper measurements in the table below. Table 3: Two-Point Discrimina5on Test Results Body Region LeM-Side Caliper Measurement Right-Side Caliper Measurement Scalp 3.5 4.0 Forehead 2.0 2.0 Lips 1.5 2.0 Front of Neck 3.0 3.0 Back of Neck 1.5 1.5 Shoulder 3.5 3.5 Upper Arm 3.0 3.0 Elbow 1.5 1.0 Forearm 2.5 2.5 Wrist 4.0 3.5 Back of Hand 1.5 1.5

Your preview ends here

Eager to read complete document? Join bartleby learn and gain access to the full version

Access to all documents
Unlimited textbook solutions
24/7 expert homework help

Lab 5 Tissues and Skin BIO201L Results and Discussion 1. Was your hypothesis stated in Ques(on 1 of the introductory ques(ons correct? If not, why do you think this is the case? The findings supported my hypothesis, showing that the fingerBps had the highest concentraBon of skin receptors, aligning with their role in fine motor skills and the need for heightened tacBle sensiBvity. This validates the noBon that body areas requiring precise sensory input possess more receptors. Meanwhile, the back, less involved in detailed touch, had fewer receptors, as expected. 2. Which region was most sensi(ve to this test? Which was least sensi(ve? most sensiBve- palms, fingerBps least sensiBve- scalp 3. Was there a difference between the measurements of the le‘ and right side of the body? Why or why not? Observed measurements varied, with some higher on the lek side and others on the right, likely due to an asymmetrical distribuBon of touch receptors. Palm of Hand 1.0 1.0 Tip of Thumb 2.5 2.5 Tip of Index Finger 2.0 2.0 Tip of Middle Finger 2.0 2.0 Tip of Ring Finger 1.5 1.5 Tip of Pinkie 1.0 1.0 Body Region LeM-Side Caliper Measurement Right-Side Caliper Measurement

Lab 5 Tissues and Skin BIO201L EXPERIMENT 5: INTRODUCTION TO THE FETAL PIG Introduc>on Ques>ons 1. Why is the fetal pig an appropriate choice for this experiment? Fetal pigs are effecBve for anatomical study due to their similarity to human anatomy, ethical sourcing, and clear Bssue preservaBon, making them valuable for hands-on educaBonal use. Data and Observa>ons Take note of your observa(ons in the table below. Ensure you provide enough detail such that you demonstrate your knowledge on the subject and that you note any features which were men(oned in the experimental procedure. The observa(ons you state must also match the photo you provide. Table 4: External Observa5on of the Fetal Pig Area Observa>ons Skin A delicate hue, blending light brown with hints of pink, and a smooth, so‘ texture. Head Region Closed eyes, protruding tongue Neck Region Creased Trunk Region The longest segment displayed uniform hair coverage across the skin, and the umbilical cord was s(ll aRached. Tail Region (including sex of pig) so‘&smooth, female

Lab 5 Tissues and Skin BIO201L Insert a high resolu(on photo of the fetal pig you observed in the dissec(on tray. Your handwriRen name and access code must be clearly visible in the background . Photos that are of too low resolu(on, that appear inauthen(c, that appear edited, or that do not show the pig, dissec(on tray and a clearly wriRen name and access code will be rejected.

Your preview ends here

Eager to read complete document? Join bartleby learn and gain access to the full version

Access to all documents
Unlimited textbook solutions
24/7 expert homework help

BIO201 Lab 5

Related Documents