exam 1

.pdf

School

Texas A&M University *

*We aren’t endorsed by this school

Course

320

Subject

Biology

Date

Apr 3, 2024

Type

pdf

Pages

Uploaded by SeanTran

Exam 1 BIMS/GENE 320 2024 Printed Name __________________________ Multiple Choice (2 points each) 1. In his monohybrid crosses, Mendel deduced that one trait was recessive because _____. A. that trait was not present in the F 1 and did not reappear in the F 2 B. that trait was present only in the F 2 C. that trait was not present in the F 1 and reappeared in the F 2 D. that trait was present in the F 1 and in the F 2 E. that trait was present only in the parents 2. What does OMIM stand for? A. Obesity and Multifactorial Impact Mutations B. Only Mendelian Inherited Mutations C. Original Mutations in Mitosis D. OMIM is a common symbol used in human medicine E. Online Mendelian Inheritance in Man 3. When discussing the complicated issues of human multifactorial traits in class, we introduced the concept of the “threshold model.” This model helps to understand the frequency of a disorder among relatives compared with the frequency of the disorder among the general population. What human disorder did we discuss in class that is clinically handled as a “threshold disorder?” A. Eye color B. Diabetes C. One type of skin cancer D. None of these disorders were discussed in relationship to multifactorial traits E. Progeria 4. What is genomics? A. the study of genomes and their genetic content, organization, function and evolution. B. the complete chromosome set in a cell. C. the total haploid set of DNA sequences carried by an individual D. all of the DNA, RNA and protein in an individual cell E. None of these answers define a genomics 5. What Mendel called “factors” we now call ____ . A. nucleotides B. bases C. genes D. chromosomes E. DNA 6. In the ABO multiple allele system, there are the following combinations of genotypes and phenotypes: A. 4 genotypes, 6 phenotypes B. 4 genotypes, 4 phenotypes C. 6 genotypes, 4 phenotypes D. 6 genotypes, 6 phenotypes E. 3 genotypes, 4 phenotypes 7. A 10 year old boy has a serious disorder known as cystic fibrosis and his younger sister has the same disorder. Neither of the children’s parents have the disorder. Assuming this is a genetic trait, what is the most likely inheritance pattern of this disorder?

A. Autosomal dominant B. It is not possible to tell the inheritance pattern from this information. C. X-linked dominant D. X-linked recessive E. Autosomal recessive 8. Mendel’s principle of independent assortment is directly related to an event that occurs in _____ of meiosis. A. anaphase I B. prophase I C. metaphase II D. prophase II E. metaphase I 9. A child is born with a lethal dominant allele. This would seem to be impossible since either parent, had they possessed this allele, would have suffered its lethal effects. What is a possible explanation? A. The allele could have varied expressivity and not always be lethal. B. The allele could have delayed onset. C. The child's allele is a spontaneous mutation that neither parent had to deal with. D. All of these are possible. E. None of these is possible. 10. Which of the following is an event that does NOT occur in prophase of mitosis? A. The nuclear envelope starts to break up. B. The mitotic spindle begins to form. C. The chromosomes line up on the equator of the cell. D. The chromosomes begin to condense. E. All of these are events that occur in prophase of mitosis. 11. Which of the following is a goal of human pedigree analysis? A. To determine the severity of the disorder B. To determine the molecular cause of a phenotype C. To determine how DNA replicates D. To determine the inheritance of non-genetic traits. E. None these things can be determined using pedigree analysis 12. What is the chance that a woman who has a recessive form of X chromosome red/green color blindness will have a son who is not color blind? A. 25 percent B. 100 percent C. 50 percent D. 0 percent E. 75 percent 13. One of the important properties of genes is that they have the ability to "recombine." This refers to their ability to ____. A. be transmitted from parents to children B. undergo changes C. break into pieces and then reassemble D. be turned on and off E. move from one chromosome to another 14. In meiosis, what is physically exchanged during the process of crossing-over? A. mitochondrial DNA.

B. regions of non-sister chromatids. C. usually abnormal karyotypes. D. only single copy genes and a few gene families. E. none of these. 15. Mendel is considered the “Father of Genetics”. His work on the transmission of “factors’ in pea plants is applicable to ____. A. all plants, but only plants B. all organisms on this planet C. really only pea plants D. none of these are true E. all plants and a few animals 16. In genetics, alternate forms of a gene are best described as _____. A. homozygous B. loci C. alleles D. homologues E. heterozygous 17. A cell that could not form spindle fibers could not complete ____. A. protein synthesis B. mitosis C. DNA replication D. cellular energy production E. gas exchange across the plasma membrane 18. In a cross involving mitochondrial inheritance _____. A. the dominant phenotype is expressed in the F 1 B. F 1 heterozygotes almost never have a phenotype like one of the parents C. the phenotypic ratio and genotypic ratio in the F 2 are identical D. Mendelian rules do not apply E. the recessive phenotype is expressed in the F 1 19. If a man expresses a Y-linked trait, we can draw the following conclusion: A. His mother most likely had the mutation gene. B. Some of his brothers may also show the trait. C. His mother was heterozygous or homozygous for the trait. D. none of these are true. E. His father most likely did not transmitt the trait to his son. 20. If a large pedigree of 5 generations shows only affected males in each generation, what is the most likely mose of inheritance? A. Autosomal recessive inheritance B. X-linked recessive inheritance C. X-linked dominant inheritance D. Y-linked inheritance E. None of these explain this type of inheritance. 21. Normal human haploid gametes (sperm and eggs) contain: A. 92 chromosomes B. 46 chromosomes C. 23 chromosomes and 46 chromatids

D. none of these are true E. 23 chromosomes 22. The phenotype is _____. A. never homozygous B. controlled by the genotype C. the result of inheritance from both parents D. the expression of a trait in an organism E. all of these 23. A man is heterozygous for two genes that occur on autosomes. Just concerning these two genes, how many different types of sperm cells can he produce and in what proportions? A. 2 in the ration of 1:1 B. 5 in the ratio of 1:2:3:2:1 C. 16 in the ration of 9:3:3:1 D. 4 in the ratio of 1:1:1:1 E. none of these are correct. 24. In humans, autosomes represent ____. A. all chromosomes including the sex chromosomes B. chromosome pairs with unlike members C. those chromosomes found only in gametes D. all chromosomes other than the sex chromosomes E. the half of the chromosomes inherited from one parent 25. Twins are said to be concordant for a trait when A. only fraternal twins exhibit the trait. B. fraternal twins more often show the trait than identical twins C. only identical twins exhibit the trait. D. both twins exhibit the trait. E. none of these is true. 26. If a trait is inherited in an autosomal recessive fashion, which of the following is true? A. All of these are true. B. About one-fourth of the offspring of two heterozygotes will be affected. C. Two affected individuals cannot have an unaffected child. D. The trait often appears in the progeny of unaffected parents. E. Both sexes are equally affected. 27. For cells in culture, the Hayflick limit describes ____. A. the size limit to which a cell can grow B. the largest number of chromosomes an organism can possess C. how rapidly DNA replication occurs D. none of these are true E. the number of divisions a cell can undergo 28. Parents with normal pigmentation have an albino daughter. What is the chance that their next two children are males and have normal pigmentation? A. 1/4 B. none of these C. 1/2 D. 3/4 E. 1/16

Your preview ends here

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