Quiz 5 Bio 110

A common feature shared by DNA replication, transcription and translation in eukaryotes is that all three processes: A) produce a polymer from monomers. B) take place within the nucleus. C) require a supply of nucleotides. D) take place within the cytoplasm.

A

Based upon what you know about the position of genes and the frequency of crossing-over between them, which gametes would you expect to be produced more often by crossing over? A) Gametes with the genotypes ab and AB. B) Gametes with the genotype aB and Ab. C) Gametes with the genotype CD and cd. D) Gametes with the genotype Cd and cD

A

In fruit flies, a gene for eye color is found on the X chromosome. Red eyes are dominant and white-eyes are recessive. If a female who is heterozygous for eye-color is mated to a male with red eyes, what are the expected phenotypes in their offspring? A) All females will have red-eyes, half of the males will have red eyes and half will have white eyes. B) All females and all males will have red eyes. C) Half of the females will have red eyes and half will have white, all males will have red eyes. D) All females and all males will have white eyes.

A

In humans, males tend to have sex linked disorders A) more frequently than females. B) less frequently than females. C) There is no difference in frequency of sex linked disorders in males and females.

A

Normally, human females have two X chromosomes and males have one. In spite of this, males do not have less of the proteins produced by the genes on the X chromosome. This is because A) one X chromosome is inactivated in the cells of females. B) males have X chromosomes that are double the size of female X chromosomes. C) the Y chromosome has all the genes that are on the X chromosome. D) the genes on the X chromosome are only expressed in females, so have no effect in males.

A

Which of the following is true about DNA polymerase? A) It can synthesize DNA in the 5' to 3' direction B) It can synthesize DNA in the 3' to 5' direction C) It can synthesize mRNA in the 3' to 5' direction D) It can synthesize mRNA in the 5' to 3' direction

A

Which of the following sequences of DNA was produced using this strand as a template? 5' ACAGTCGAGCCTCGT 3' A) 3' TGTCAGCTCGGAGCA 5' B) 3' ACGAGGCTCGACTGT 5' C) 3' ACAGTCGAGCCTCGT 5' D) 3' UGUCAGCUCGGAGCA 5'

A

You are studying two different autosomal genes and each gene has two alleles. Each allele is either completely dominant or recessive. You cross one parent that is homozygous recessive with a parent that is heterozygous for both genes, and observe four phenotypic classes in a ratio of 1:1:1:1. You conclude that A) the genes may or may not be on the same chromosome. B) the genes can only be on different chromosomes. C) the genes can only be on the same chromosome D) you can't tell if these genes are linked because crossing-over might have occurred between sister chromatids during anaphase II.

A

Which of the following statements is true of linked genes? Select all that apply. A) They assort independently because they are found on different chromosomes. B) They do not assort independently because they are found on different chromosomes. C) They experience crossover at frequencies proportional to the distance between them. D) They are the result of a mutation in a sister chromatid.

A & C

Which of the following is true of an inactive X chromosome? A) It appears as a Barr Body. B) It is always the maternal X that is inactivated. C) It is inactivated by the action of a gene on the Y chromosome. D) The gene responsible for inactivation is the XIST gene.

A & D

A woman has red-green colorblindness and she is married to a man with normal vision. Which of the following statements is true? Select all that apply. A) All of her sons will have red-green colorblindness. B) Her father has red-green colorblindness. C) All of her daughters will be carriers for red-green colorblindness. D) Half of her sons will have normal vision and half will be red-green colorblind.

A, B & C

Which of the following is true of the genetic code? Select all that apply. A) It is universal. B) Several different codons can encode the same amino acid. C) Bacteria use a different genetic code than eukaryotes. D) A group of 3 bases codes for an amino acid or a stop codon. E) The mRNA is read by the ribosome in an overlapping fashion.

A, B, D

Calico coat coloration in cats is the result of a gene on the X-chromosome. Cats that are heterozygous for this gene are calico. However, male calico cats are rare because A) X-inactivation only occurs in females. B) a male would need to have XXY chromosomes. C) the gene for coat color is on the Y chromosome in males.

B

During DNA replication, the enzyme primase is responsible for A) initiating replication by synthesizing a DNA primer. B) initiating replication by synthesizing an RNA primer. C) initiating replication by unwinding the DNA double helix. D) synthesizing the DNA polymer.

B

The process of DNA replication occurs A) during mitosis, producing sister chromatids. B) during interphase, producing sister chromatids. C) during interphase, producing homologous chromosomes. D) during mitosis, producing homologous chromosomes.

B

The recessive alleles for scute bristles (s) and vestigial wings (v) identify two autosomal genes on the third chromosome of Drosophila melanogaster. When females, heterozygous at these two genes (Ss Vv), were crossed with scute-bristled, vestigial winged males, the following classes and numbers of progeny (n=1000) were obtained: Wild-type bristles, wild-type wings: 108 Wild-type bristles, vestigial wings: 382 Scute bristles, vestigial wings: 112 Scute bristles, wild-type wings: 398 Based upon these results, the map distance between the s and vg genes is estimated to be A) 10.8 map units B) 22.0 map units. C) 38.2 map units. D) 78 map units. E) Greater than 50 map units so the genes are unlinked.

B

This is a karyotype (picture of a person's chromosomes) from a boy with Klinefelter syndrome. How many Barr bodies would you expect to find in this boy's cells? A) 0 - males don't produce Barr bodies B) 1 C) 2 D) 3

B

Which of the following parental crosses could have given rise to the females used in the cross described above? All parent individuals are true breeding. A) wild-type bristles, wild-type wings X scute bristles, vestigial wings B) wild-type bristles, vestigial wings X scute bristles, wild-type wings C) scute bristles, vestigial wings X scute bristles, vestigial wings D) wild-type bristles, wild-type wings X wild-type bristles, wild-type wings

B

You are studying a molecule of DNA and note that the 22% of the bases are adenine. What percent of the molecule should be guanine? A) 22% B) 28% C) 44% D) 56%

B

Which of these is true of translation? Select all that apply. A) The information in a DNA molecule is used to produce a protein. B) The transfer RNAs bring amino acids to the ribosome. C) The process continues until a stop codon is reached. D) The mRNA provides the information to direct the synthesis of a polypeptide. E) It occurs in the nucleus.

B, C & D

Consider the relative distance between four genes on a chromosome as shown here. What is the expected recombination frequency between genes A and C? A-------6 m.u.-------B----8 m.u.----C---------7 m.u.------D A) 21% B) 8% C) 14% D) 7%

C

Hunter's syndrome is a sex-linked recessive disease. A man with Hunter's syndrome and a woman without the disease (but her father had the disease) are having a daughter. What is the likelihood that she will have the disease? A) 0 B) 1/4 C) 1/2 D) 1

C

In a species of yeast, the tRNA population does not contain any tRNAS with the anticodon 3' ACC 5'. During translation, these yeasts could not produce any polypeptides that contain the amino acid: A) Thr B) Gly C) Trp D) Pro

C

In birds, sex is determined by a ZW chromosome scheme. Males are ZZ and females are ZW. A recessive lethal allele that causes death of the embryo is sometimes present on the Z chromosome in pigeons. What would be the sex ratio in the offspring of a cross between a male that is heterozygous for the lethal allele and a normal female? A) 1:1 male to female B) 4:3 male to female C) 2:1 male to female D) 3:1 male to female

C

In humans and other mammals, males, have XY sex chromosomes and are___________ and produce two different kinds of gametes, whereas females with XX sex chromosomes are ___________ and produce only one kind. A) homogametic; heterogametic B) dioecious; monoecious C) heterogametic; homogametic D) monoecious; dioecious E) monoecious; heterogametic

C

Okazaki fragments are joined together by: A) RNA polymerase. B) DNA polymerase. C) Ligase D) Helicase E) Primase

C

Okazaki fragments are produced along the lagging strand of DNA. This is because replication proceeds ___________ the replication fork, and DNA polymerase adds nucleotides to the _______ end of the newly synthesized strand. A) toward / 3' B) toward / 5' C) away from / 3' D) away from / 5'

C

Ribosomes need both mRNA and tRNA to help complete the process of protein synthesis. Which statement correctly describes their roles? A) tRNA builds the ribosome, while mRNA translates the nucleus into a protein. B) mRNA helps the tRNA translate the ribosome into a protein. C) tRNA translates the code in the mRNA into a string of amino acids. D) Ribosomes build tRNAs, which are translated into mRNA messages.

C

True or False? Human males with a normal complement of chromosomes can be carriers for sex-linked traits. A) True because both males and females can express recessive traits. B) True because the Y chromosome can carry the recessive allele. C) False because males only have one copy of the X chromosome. D) False because males don't have sex chromosomes.

C

What proportion of the female's gametes are (s v)? A) 10.8% B) 38.2% C) 11.2% D) 39.8%

C

When you examine the polypeptide encoded by this template DNA, what type of mutation has occurred? Normal allele: 3' TTTGTAACG 5' Mutant allele: 3' TTTGTAACT 5' A) The loss of the start codon. B) The substitution of an amino acid with a different amino acid. C) The substitution of an amino acid with a stop codon. D) The mutation is silent due to the redundancy of the genetic code.

C

Which form of RNA carries amino acids to the ribosome during translation? A) rRNA B) mRNA C) tRNA

C

You start your experiment with the genotypes AABB and aabb in the P generation. You then cross one of their offspring, with the genotype AaBb, to an individual with the genotype aabb (the F1 generation). If these two genes are completely linked, which of these genotypes could you see in the F2, the offspring of this AaBb and aabb cross? A) Only AAbb B) Only aaBB C) AaBb and aabb D) AaBb, Aabb, aaBb, and aabb

C

Crossing-over occurs between __________________ and occurs at ________________ locations along the length of the chromosomes. A) sister chromatids/predetermined B) sister chromatids/random C) nonsister chromatids/predetermined D) nonsister chromatids/random

D

In corn plants, the yellow kernels (Y) are dominant to white kernels (y) and smooth kernels (S) are dominant to shrunken (s). When females corn plants that are heterozygous at these two genes (YySs) were crossed with white, shrunken kerneled males, the following classes and numbers of progeny (n=1000) were obtained: Yellow kernel, Smooth kernel: 254 Yellow kernel, Shrunken kernel: 253 White kernel, Smooth kernel: 246 White kernel, Shrunken kernel: 247 Which of the following statements about the distance between these two genes is true? A) These two genes are 25 map units apart. B) These two genes are 50 map units apart. C) These two genes are located on different chromosomes. D) These two genes could either be 50 or more map units apart, or could be on different chromosomes.

D

In the diagram above, A and B refer to which ends, respectively? A) A= 3' and B = 3' B) A = 3' and B = 5' C) A = 5' and B = 3' D) A = 5' and B = 5'

D

The pedigree above tracks Duchenne Muscular Dystrophy (DMD) through several generations. DMD is an X-linked recessive trait. If individuals I-1 and I-2 had another son, what is the chance that he would have DMD? A) 0% B) 25% C) 50% D) 100%

D

You have just sequenced a new gene from a species of fish and you want to determine the sequence of the polypeptide that the gene encodes. The template strand from the first 15 bases of the gene is given below. What is the sequence of amino acids in the polypeptide encoded by this gene? 3' TAC TTA CGC AAG CCG 5' A) TYR - LEU - ARG - LYS - PRO B) MET - TYR - PRO - ASP - GLY C) ALA - VAL - ARG - ILE - HIS D) MET - ASN - ALA - PHE - GLY

D