Biology 1081 Unit 3 Mock Exam PDF

BIOLOGY 1081 Mock Exam Unit 3 Choose the answer that best completes the statement or answers the question. 1. Homologous chromosomes 6. Crossing over occurs a. Carry information for the same traits a. During metaphase I and allows the b. Carry...

BIOLOGY 1081 Mock Exam Unit 3 Choose the answer that best completes the statement or answers the question. 1. Homologous chromosomes 6. Crossing over occurs a. Carry information for the same traits a. During metaphase I and allows the b. Carry identical genetic information chromosomes to line up at the equator of the c. Are separated from each other in anaphase II cell d. Carry the same alleles b. During prophase II and allows the sister chromatids to exchange genetic information 2. An animal cell undergoes cytokinesis, forming the c. During telophase I and allows the cells to get cleavage furrow through ready for meiosis II a. Microtubules forming a contractile ring d. During prophase I and allows the homologous b. Actin filaments creating a contractile ring chromosomes to exchange genetic information c. Phospholipid membrane forming a wall, with each other separating the two cells d. Actin filaments pulling apart the two cells 7. Which of the following is true? a. Cyclin stays at a constant concentration 3. A certain animal has two unlinked genes: one for ear throughout the entirety of the cell cycle shape (E) and one for coat color (C). The animal has a b. CDKs stay at a constant concentration genotype of EeCc. Which of the following genotypes throughout the entirety of the cell cycle is possible in a gamete from this organism? c. Cyclins are enzymes that regulate cell division a. Ee d. CDKs are proteins that fluctuate in b. E concentration throughout the progression of the c. ec cell cycle d. EeCc 8. In strawberries, the color of the stem and the color 4. Barr bodies of the seeds are on genes that are close together on the a. Are formed in males same chromosome, meaning that they cannot assort b. Are formed in females independently. What is this an example of? c. ethanol fermentation a. linkage d. glycolysis b. epistasis c. Mendelian inheritance 5. In cats, the gene for coat color is found on the X d. pleiotropy chromosome. A female embryo has one orange coat color allele (O) and one black coat color allele (B). 9. Sister chromatids separate during Which of the following is correct about this embryo? a. Anaphase of meiosis II a. It will become a black cat since the allele for b. Metaphase of meiosis II orange coat color is recessive c. Anaphase of meiosis I b. It will be either orange since the chromosome d. Prophase of meiosis I carrying the black allele will be inactivated c. It will become an orange cat since the allele for 10. Interphase involves all of the following steps black coat color is recessive EXCEPT d. It will become a calico cat a. Cell growth b. DNA replication  c. The condensation of chromatin 15. A healthy human cell undergoes meiosis, resulting d. Production of cellular components necessary in four gametes. Which of the following is true? for mitosis a. After meiosis I, the cells are diploid b. After meiosis I, the cells are haploid 11. Place the following events of mitosis in the correct c. After meiosis II, the cells are diploid order. d. After meiosis I, the cells have homologous I. Sister chromatids align on the metaphase plate. chromosomes in each cell II. The cleavage furrow forms. III. The nuclear membrane breaks up. 16. A couple has a child with Down syndrome. The IV. Sister chromatids condense. mother is 39 years old at the time of delivery. Which V. Sister chromatids separate. of the following is the most probable cause of the child's condition? a. III, IV, I, V, II a. The mother had a chromosomal duplication b. III, I, IV, III II b. One member of the couple underwent c. IV, III, I, V, II nondisjunction in somatic cell production. d. IV, I, V, III, II c. The woman inherited this tendency from her parents 12. Which of the following statements about sister d. The mother most likely underwent chromatids is true? nondisjunction during gamete production a. Sister chromatids are produced only during mitosis. 17. Color blindness is a sex-linked recessive trait in b. After mitosis, sister chromatids contain the humans. Two people with normal color vision have a same genes, but they may have different alleles. color-blind son. What are the genotypes of the parents? c. Sister chromatids are exact copies of each other a. XNXn and XNY and are formed just prior to cell division. b. XNXN and XNY d. After mitosis, sister chromatids contain the c. XNXN and XnY same genes, but they may have different alleles. d. XnXn and XnY 13. A species that has three sets of homologous 18. A black rabbit crossed with an albino rabbit chromosomes (AaBbCc) can have __ different produced twelve black offspring. When the albino was combinations of chromosomes in its gametes? crossed with a different black rabbit, six black and six a. 6 albinos were produced. What is the best explanation b. 3 for this genetic situation? c. 8 a. Albino and black are codominant. d. 2 b. Albino is dominant; black is incompletely dominant. 14. When a pink flower is self-fertilized, the offspring c. Albino is recessive; black is codominant. are red, pink, or white. What type of inheritance d. Albino is recessive; black is dominant. pattern does flower color exhibit in this example? a. dominance 19. Black fur in mice (B) is dominant to brown fur (b). b. codominance Short tails (T) are dominant to long tails (t). What c. incomplete dominance fraction of the progeny of crosses BbTt × BBtt will be d. euploidy expected to have black fur and long tails? a. 1/16 b. 1/8  c. 1/2 a. Are both present in every somatic cell of males d. 1/4 and females b. Include genes that determine an individual's sex 20. In mice, coat color is controlled by two genes: the c. Are the same size and have the same number of A gene determines if the coat will be agouti (a mix of genes black and yellow bands on each hair), and the C gene d. Are condensed in the form of Barr bodies when determines whether any pigment is produced at all. If a not replicating mouse has two recessive alleles (cc) for the C gene, it will have an albino (white) coat regardless of the 24. Which of the following is true? alleles present at the A gene. a. Cell division is unregulated Which of the following best explains this genetic b. Homologous chromosomes are connected at the interaction? kinetochore a. The A gene is pleiotropic, affecting both the c. Chiasmata is visible between two sister pattern and color intensity of the coat. chromatids during prophase b. The C gene is epistatic to the A gene, as it d. Chiasmata is visible during prophase I determines whether any pigment will be deposited in the fur. 25. A cell begins to replicate out of control. Under c. The A gene displays incomplete dominance, closer inspection, it is found that the original cell had affecting the shade of the coat color in all synthesized the copy of DNA incorrectly during cases. replication. Which checkpoint should have caught this? d. The C gene shows codominance with the A a. G1/S gene, resulting in a blend of albino and agouti b. G2/M coat colors. c. Spindle d. GBM 21. Males are more often affected by sex-linked traits than females because _____. 26. Albinism is an autosomal recessive trait. A man a. Female hormones such as estrogen often and woman are both of normal pigmentation and have compensate for the effects of mutations on the one child out of three who is albino (without melanin X chromosome pigmentation). What are the genotypes of the albino's b. Males are hemizygous for the X chromosome parents? c. Females produce Barr bodies to reduce the a. One parent must be homozygous for the effect of a harmful sex-linked trait recessive allele; the other parent can be homozygous dominant, homozygous recessive, 22. A male is heterozygous for the trait that produces or heterozygous. freckles on the skin, and he has freckles. If he marries b. One parent must be heterozygous; the other a woman who is also heterozygous for freckles, parent can be homozygous dominant, ______ percent of their children are predicted to be homozygous recessive, or heterozygous. freckled. Also, of all their children, ______ percent are c. Both parents must be heterozygous predicted to be heterozygous. d. One parent must be homozygous dominant; the a. 25; 100 other parent must be heterozygous b. 75; 50 c. 50; 50 27. In carrots, orange carrot color (C) is dominant over d. 25; 75 (c) yellow carrots. Dark green stems (G) are also dominant over light, sage colored stems (g). A plant 23. In humans, the X and Y chromosomes _____ with orange carrots and dark green stems is crossed with a carrot with a yellow carrot with sage stems. This b. Rr and Rr cross produces the following offspring: c. rr and rr - Orange carrot with green stems: 545 d. Rr and rr - Orange carrot with white stems: 12 - Yellow carrot with green stems: 15 31. Marfan syndrome, a genetic condition caused by a - Yellow carrot with white stems: 553 mutation in the FBN1 gene, causes long limbs, What is the recombination frequency of this cross? cardiovascular issues, and vision problems. This wide a. 7.8 cM range of symptoms is because the FBN1 gene affects b. 7.8 λm multiple systems in the body. Which of the following c. 2.4 λm best explains why a single mutation in the FBN1 gene d. 2.4 cM causes such varied symptoms? a. The FBN1 gene directly codes for several 28. A human cell undergoing meiosis has different proteins, each affecting a separate part nondisjunction at chromosome 21. What has occurred of the body. here? b. The FBN1 gene undergoes multiple mutations a. The G1/S checkpoint failed to check that the to produce different effects in different organs. DNA was undamaged before replication c. The FBN1 gene exhibits pleiotropy, meaning it b. The G2/M checkpoint failed to check that the influences multiple traits across different organ DNA was replicated properly systems. c. The spindle checkpoint failed to ensure d. The FBN1 gene has an incomplete dominance spindles were attached at all chromosomes effect, leading to a variety of symptoms in the before anaphase I or II could occur body. d. The spindle checkpoint failed to check that the 32. You observe a sample of onion root tip cells under DNA was replicated properly a microscope and notice that some cells have chromosomes lined up along the center of the cell, 29. In mice, the allele for insulin-like growth factor 2 while others have chromosomes being pulled toward (lgf2) is an autosomal Mendelian trait in which the opposite poles of the cell. maternal allele is silenced. The recessive allele can Which of the following best explains what is prevent normal growth. What proportion of offspring happening in these different cells? will have normal growth if a homozygous dominant a. The cells with chromosomes aligned in the mother is crossed with a carrier father? center are in metaphase, while the cells with a. 1/2 chromosomes being pulled apart are in b. 1/4 anaphase. c. 3/4 b. The cells with chromosomes aligned in the d. All will have normal growth center are in prophase, while the cells with chromosomes being pulled apart are in 30. In peonies, red petals (R) are dominant over white telophase. petals (r). A gardener is attempting to grow only red c. The cells with chromosomes aligned in the peonies, but she is unsure that the red peonies she center are in telophase, while the cells with bought are purebred. She decides to run a test cross on chromosomes being pulled apart are in them, finding out 30 out of the 60 offspring are red, prophase. and the other 30 are white. d. The cells with chromosomes aligned in the What are the genotypes of the flowers involved in the center are in anaphase, while the cells with test cross? chromosomes being pulled apart are in a. RR and rr metaphase. 33. A geneticist is studying the inheritance of two traits 34. In a genetics experiment, a plant with purple in pea plants: seed shape (round or wrinkled) and seed flowers (heterozygous genotype, Pp) is crossed with a color (yellow or green). They notice that these traits plant with white flowers (homozygous recessive, pp). are inherited independently and that crossing two The offspring display a 1:1 ratio of purple to white heterozygous plants (RrYy) results in offspring with a flowers. 9:3:3:1 ratio of phenotype combinations. Which of the following best explains why this ratio Which of the following best explains why? occurs in the offspring? a. The traits are linked and always inherited a. The purple and white flower color alleles together due to their location on the same undergo independent assortment, resulting in chromosome. equal expression of each allele. b. The traits undergo independent assortment, b. The law of segregation states that each parent’s meaning each trait is inherited independently of alleles for flower color separate, so each the other due to the random alignment of gamete receives only one allele, resulting in a chromosomes during meiosis. predictable 1:1 phenotypic ratio in the c. The traits exhibit incomplete dominance, offspring. resulting in a blending of phenotypes. c. The law of independent assortment ensures that d. The traits show codominance, resulting in both only the purple flower color is expressed in all phenotypes being equally expressed in each offspring due to the dominance of the P allele. offspring. 38. Draw a picture of a cell in a certain phase of meiosis that would cause ALL of the resulting gametes to be aneuploid. Label the phase in which this occurs. 39. In an imaginary species of cows, red coat color (CR) and white coat color (CW) are codominant over black coat color (c). Heterozygotes will appear spotted. Determine the genotypes and phenotypes of the offspring of a homozygous red cow and a heterozygous white cow, showing how you got your answers. 40. In tigers, the dominant N allele is necessary for normal sight whereas blindness is recessive (n). However, a dominant allele F at a different locus means that a tiger will be blind even if they have the phenotype for normal sight. You cross an individual with the genotype NNff with another with the genotype NnFf. What proportion of the offspring is blind?