Q: The BCRA-1 allele is associated with very high risk of breast and ovarian cancers. Is this allele…
A: The mutation accumulation (MA) theory describes that if harmful or deleterious mutations are…
Q: Using your knowledge of meiosis, explain why Drosophila progeny remain diploid? (2n=8)
A: The indirect process of cell division in which the chromosomes of parent cells divide once but…
Q: Name two ways that genetic diversity is increased during meiosis.
A: Hereditary variety is a proportion of the hereditary contrasts that exist inside a populace. The…
Q: Achondroplasia is a dominant trait that causes a characteristic form of dwarfism. In a survey of…
A: A mutation is a sudden heritable change and a random event. The frequency of mutation is known as…
Q: Butterflies have an X-Y sex-determination system that is different from that of flies or humans.…
A: -The butterfly shown has a completely unique pattern of colors because o a special trait- it has two…
Q: Explain in detail the meaning of gene fusion. How is this process related to prostate cancer…
A: A gene is referred to as the smallest structural and functional unit of heredity. They are made up…
Q: Cancers result from mutations in somatic cells,and these mutations therefore are not passedon to…
A: Mutations are the changes in the DNA sequence that can either be a change in the base pairs or can…
Q: Drosophila melanogaster has four pairs of chromosomes. Sperm for this species are formed by a…
A: The sex determination in drosophila melanogaster is determined by the XX-XO pattern in which the…
Q: The woman in Problem 24 has had two miscarriages. She has come to you, an established genetic…
A: Miscarriage is normally called pregnancy loss. It refers to the natural death of the embryo and the…
Q: Do you know of any genetic diseases or disorders that result from errors in mitosis or meiosis? How…
A: Introduction: Mitosis and meiosis are processes and fundamental stages of cell division and cell…
Q: How many Barr bodies in a person with genotype XXXXX? How is the structure of a Barr body different…
A: The mammalian males contain XY chromosome and females contain XX chromosome. So, the number of…
Q: Colorblindness and hemophilia are both X-linked traits in humans. Explain how a female who has a…
A: Colourblindness and haemophilia are both X-linked traits in humans. Haemophilia is a bleeding…
Q: three children. What is the probability that one their children will be normal (unaffected) and two…
A: Autosomal recessive mutation leads to autosomal recessive disorder. This will occur when you…
Q: Identical twins each carry the same genome, but over time, can develop different phenotypes. How can…
A: Identical twins are formed as a result of the fertilization of a single egg. The zygote later splits…
Q: During spermatogenesis, is there any difference in outcome between first- and second-division…
A: Spermatogenesis is the process of producing spermatozoa(haploid) from germ cells. In the…
Q: The maternal-effect mutation bicoid (bcd) is recessive. Inthe absence of the bicoid protein product,…
A: Introduction: Bicoid (Bcd) protein is a product of the bicoid gene having a maternal effect and is…
Q: sex determenination.
A: In humans males are heterogametic and females are homogametic. heterogametic means production of…
Q: Why are people with balanced chromosomal translocations phenotypically normal? Do they suffer from…
A: Chromosomal translocations are genomic events in which either a part or the entire chromosome breaks…
Q: company that offers PGD terms an embryo “normal and healthy” if it has 46 chromosomes. Why is this…
A: Genetic testing of in vitro embryos is a strong technology where a small number of cells are…
Q: Are mutations that arise during mitosis or meiosis the same?
A: The genetic material consists of a nucleotide sequence that results in the expression of the…
Q: couple has one daughter with Tay-Sachs disease and three other unaffected children. Neither the…
A: Tay-sachs disease appears after birth due to deficiency of enzyme beta-D-N -acetyl…
Q: In the small intestine, stem cells in the crypts divide asymmetrically to maintain the population of…
A: Villi are projections into the lumen of small intestine and are covered with absorptive, mature…
Q: In humans, males are heterogametic and females are homogametic, Explain. Are there any examples…
A: Answer In humans the 23rd pair of chromosomes contains.
Q: Which findings support the fact that the presence of the Y- chromosome rather than the lack of a…
A: In many animals including humans, sex is determined by sex chromosomes, which are X and Y…
Q: During meiosis in male mammals, sex chromosomes segregate to produce two types of sperm: X‑bearing…
A: In mammals sex determination is male heterogametic type in which the male produces two types of…
Q: Answer the following questions given the pedigree below. Please assume that no other mutations are…
A: A pedigree chart is a type of diagram that shows the occurrence and appearance of phenotypes of a…
Q: Mutations in genes that affect meiosis have been identified in many different model organisms. Most…
A: Meiosis is the process of division of a cell in which four daughter cells are produced. The…
Q: Explain in detail 2 human chromosomal disorders. What is the chromosomal abnormality? What are the…
A: A chromosomal disorder is a anomaly, aberration, or mutation is a missing, extra, or irregular…
Q: Tay-Sachs disease most likely demonstrates what type of inheritance? Pedigree information…
A: Mutated genes are located on the non-sex chromosome and the traits for disease get transferred…
Q: Cystic fibrosis is a recessive disease that affects many parts of the body, but primarily presents…
A: The CFTR gene codes for the protein cystic fibrosis transmembrane conductance regulator (CFTR). The…
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- The maternal-effect mutation bicoid (bcd) is recessive. Inthe absence of the bicoid protein product, embryogenesis isnot completed. Consider a cross between a female heterozygousfor the bicoid mutation (bcd+/ bcd-) and a homozygousmale(bcd-/ bcd-). How is it possible for a male homozygous for the mutationto exist?The BCRA-1 allele is associated with very high risk of breast and ovarian cancers. Is this allele consistent with the mutation accumulation theory or the antagonistic pleiotropy theory of senescence? Why? A couple of sentences answer is fine.Cancers result from mutations in somatic cells,and these mutations therefore are not passedon to gametes. However, some families havemuch higher rates of cancer than average,showing that there are heritable factors thatcontribute to the risk of developing cancer. Discuss the roles that somatic mutations and germline mutations play in producing cancer.
- Theodor Boveri predicted that malignancies would often be associated with chromosomal mutation. What lines of evidence substantiate this prediction?Fragile-X syndrome causes the most common form of inherited intellectual disability. What is the chromosomal abnormality associated with this disorder? What is the phenotype of this disorder?Why are people with balanced chromosomal translocations phenotypically normal? Do they suffer from reduced fertility? Why?
- The maternal-effect mutation bicoid (bcd) is recessive. Inthe absence of the bicoid protein product, embryogenesis isnot completed. Consider a cross between a female heterozygousfor the bicoid mutation (bcd+/ bcd-) and a homozygousmale(bcd-/ bcd-). Predict the outcome (normal vs. failed embryogenesis) inthe F1 and F2 generations of the cross described.The woman in Problem 24 has had two miscarriages. She has come to you, an established genetic counselor, with these questions: Is there a genetic explanation of her frequent miscarriages? Should she abandon her attempts to have a child of her own? If not, what is the chance that she could have a normal child? Provide an informed response to her concerns.In the small intestine, stem cells in the crypts divide asymmetrically to maintain the population of cells that make up the villi; after each division, one daughter remains a stem cell and the other begins to divide rapidly to produce differentiated progeny.Explain why or why not.
- Suppose a man and a woman are each heterozygous carriers of a mutation causing a fatal hereditary disease not on the RUSP list. Prenatal genetic testing can identify the genotype of a fetus with regard to this disease and can identify fetuses with the disease. What do you think are the three or four most important factors this couple should consider in their decision making about having children?Mutations in DNA that result in altered proteins can causehereditary diseases. Pedigree studies and genetic testing mayclarify the risk of disease. At the chromosome level, nondisjunctionduring meiosis can result in gametes with too few or too manychromosomes, most of which produce inviable offspring.Imprinting refers to inactivation of alleles depending on whichparent the alleles come from; offspring in whom imprinting occursappear haploid for the affected gene even though they are diploid. During spermatogenesis, is there any difference in outcome between first- and second-division nondisjunction?A company that offers PGD terms an embryo “normal and healthy” if it has 46 chromosomes. Why is this statement misleading? , Two famous male actors had twins using a surrogate mother who carried two embryos that hadbeen fertilized in vitro, one with one man’s sperm and the other with the other man’s sperm. In terms of genetics, how closely are the babies, a boy and a girl, related to each other if they have different fathers?