Deck 20: Sexual Reproduction, Meiosis, and Genetic Recombination

Question 1

As a result of nondisjunction, an individual with Turner syndrome is genotypically XO- lacking one of the sex- determining chromosomes. Taking this into account, the fusion of the gamete containing the extra chromosome with a normal gamete could result in an individual with the genotype

A)XXX.
B)XXY.
C)XYY.
D)A or B
E)A, B, or C

Answer 1

D

Question 2

Mitosis and meiosis differ in that

A)sister chromatids are separated in anaphase of mitosis.
B)homologs are separated in prophase I of meiosis.
C)sister chromatids are separated in prophase I of meiosis.
D)homologs are separated in prophase II of meiosis.
E)homologs are separated in prophase of mitosis.

Answer 2

B

Question 3

A series of three genes is known to be on the same chromosome. In examining recombination events, you obtain the following data: $\begin{array}{ll}\text {no observable recombination }&30\%\\\text {between A and } B & 15 \% \\\text { between B and } C & 35 \%\\\text { between A and } C & 20 \%\end{array}$ What is the order of genes on this chromosome?

A)ACB
B)BAC
C)ABC
D)BCA
E)cannot determine from this information

Answer 3

BAC

Question 4

All of the following are capable of reproducing by parthenogenesis EXCEPT

A)Komodo dragons.
B)bees.
C)parasitic wasps.
D)scorpions.
E)kangaroos.

Question 5

You are attempting to clone your first gene. Up to the point of screening, everything has gone well. The vector has a gene for ampicillin resistance. In addition to the gene DNA, the insert also carries a gene for streptomycin resistance. Based on restriction digest, if properly inserted into the vector, your inserted DNA should be located within the ampicillin gene. Therefore, when screening you should look for clones that are

A)ampicillin resistant and streptomycin sensitive.
B)ampicillin resistant and streptomycin resistant.
C)ampicillin sensitive and streptomycin resistant.
D)ampicillin sensitive and streptomycin sensitive.
E)Not enough information is given to determine the answer.

Question 6

During bacterial conjugation, interrupted matings yielded the following information: leu 10 minutes, arg 8 minutes, str 15 minutes, and amp 12 minutes. Based on this information, the order of the genes beginning at the origin is

A)leu- arg- str- amp.
B)amp- arg- leu- str.
C)arg- amp- leu- str.
D)arg- leu- amp- str.
E)str- amp- leu- arg.

Question 7

Charlie, an Angus bull, is heterozygous (Bb)for coat color, where B = black and b = brown. Charlie therefore has a black coat. Black is Charlie's

A)phenotype.
B)genotype.
C)homozygous state.
D)heterozygous state.
E)gene conversion.

Question 8

Of the subphases of prophase I of meiosis, the phase at which mammalian egg cells are arrested for years during oogenesis is

A)diakinesis.
B)pachytene.
C)zygotene.
D)leptotene.
E)diplotene.

Question 9

You have recently purchased a black angus bull named Maxwell, an advertised "pure- breeding" champion, for which you pay $1,000,000. You mate Max with several cows that are verified pure breeding black angus cows. Several years later, you mate different pairs of Max's offspring (F1 x F1)and find that with certain pairings, approximately one fourth of the progeny are red (F2). If B = black and b = red, what were the genotypes of the original cross, Maxwell x cow?

A)bb x bb
B)BB x BB
C)BB x bb
D)Bb x Bb
E)Bb x BB

Question 10

You purchase a black dog from a pet shop that tells you this animal is a purebred and that they will forward its papers to you at a later date. In this breed, black is dominant to white. You mate the dog with a white dog of the same breed. If the dog you purchased was a purebred animal, what approximate percentages of colors should you see in the offspring?

A)50% white, 50% black
B)100% black
C)25% white, 75% black
D)75% white, 25% black
E)100% white

Question 11

Mosses and ferns produce gametes by the process of

A)gene conversion.
B)binary fission.
C)meiosis.
D)cloning.
E)mitosis.

Question 12

The genotype of a particular pea plant is TtYy, corresponding to a phenotype of tall and yellow. How many different types of gametes are expected to be produced by this individual?

A)2
B)4
C)1
D)5
E)8

Question 13

The synaptonemal complex forms in which subphase of prophase I of meiosis?

A)leptotene
B)pachytene
C)diplotene
D)zygotene
E)diakinesis

Question 14

Which of the following is NOT a "natural" means of transferring DNA in prokaryotes?

A)transformation
B)electroporation
C)infection
D)transduction
E)conjugation

Question 15

When looking at a linear ascus of spores in Neurospora, you find the following octet: leu- leu-
+
+
Leu- leu- leu-
+
This sequence of spores most likely arose as the result of

A)gene conversion.
B)mitosis.
C)mutation.
D)meiosis II.
E)meiosis I.

Question 16

Using restriction enzymes, a eukaryotic gene is cut, ligated into a bacterial plasmid, and introduced into a strain of E. coli. To better the odds of getting expression of the eukaryotic gene in this system, you need to make certain that

A)the gene and the plasmid were cut with different restriction enzymes.
B)the gene has a eukaryotic promoter for transcription.
C)mRNA is used for ligation directly into the vector.
D)the plasmid has a prokaryotic promoter for transcription.
E)the gene product is toxic to the bacterial cell.

Question 17

An individual has the genotype AaBbCcDdEe. How many different type of gametes can this individual make?

A)625
B)32
C)5
D)10
E)25

Question 18

Fungi produce spores by which of the following processes?

A)mitosis
B)binary fission
C)cloning
D)gene conversion
E)meiosis

Question 19

Which of the following organisms spends its life cycle in the haploid state?

A)fungus
B)humans
C)bacteria
D)Drosophila
E)trees

Question 20

In studying T cell proliferation (cell division)in response to a specific antigen, you decide to stimulate these T cells with antigen and examine the genes that are activated by the interaction. To do this, following stimulation you should isolate

A)tRNA.
B)mRNA.
C)rRNA.
D)DNA.
E)plasmid DNA.

Question 21

The first disease to be treated by gene therapy was .

Question 22

How many chromatids are present in prophase I of meiosis I in a diploid cell, 2n = 12?

A)12
B)24
C)48
D)6

Question 23

Genetic variability in sexually reproducing organisms arises within

A)egg and sperm genetic recombination from distinct individuals.
B)crossover events between sister chromatids.
C)crossover events between nonsister chromatids.
D)egg and sperm genetic recombination from an individual.
E)both B and C

Question 24

During bacterial conjugation, you wish to examine genes associated with the F plasmid of your bacterial strain of interest, as you feel that it possesses an additional gene. You are able to easily determine the presence or absence of the gene you believe to be associated with the plasmid. In order to investigate this possibility, you must allow conjugation between your strain and a compatible strain that is

A)another F+ strain.
B)the same F+ strain.
C)a Hfr strain.
D)a F' strain.
E)a F- strain.

Question 25

In mosses and fungi, the process of meiosis produces

A)pollen nuclei.
B)egg cells.
C)sperm cells.
D)spores.
E)prothalli.

Question 26

A bacterial cloning vector for the cloning of large DNA fragments that was derived from an F plasmid is the

A)SacB.
B)YAC.
C)BAC.
D)Ti.
E)both A and C

Question 27

The alternative forms of a gene that can be expressed are known as

A)alleles.
B)haplotypes.
C)genes.
D)loci.
E)spores.

Question 28

The DNA of gene X in humans has been isolated, cloned, and sequenced and is 8000 base pairs in length. From cells that were actively transcribing gene X, a cDNA library was made. In this case, gene X was found to produce from a mRNA that was 4200 bases in length. The most probable explanation of these results is that

A)the DNA encoded introns that were excised during mRNA processing.
B)a mutation resulted in a large loss of this particular gene.
C)reverse transcription of the mRNA isolate was not complete.
D)there was no mRNA in the cells of the mRNA used to make the cDNA library.
E)none of the above

Question 29

The genes along a particular linear chromosome are illustrated below: The frequency of crossover events between these loci will be least frequent when considering genes

A)b and c.
B)d and e.
C)c and d.
D)a and e.
E)a and b.

Question 30

In bacterial cells, a cell that had the F plasmid integrated into the chromosome is known as

A)F+.
B)F'.
C)Hfr.
D)F- .
E)none of the above

Question 31

Metaphase II arrest is mediated by , a biochemical activity present in mature eggs.

Question 32

It is your task to prove the chromosomal theory of inheritance in your cell biology class. Your task is limited by examining only one trait in Drosophila. You may use the tools of modern biotechnology to aid you in your progress. Which of the following would be least likely to help you in your endeavor?

A)examining a trait that is the genotype AA in all of the available parental stocks
B)genetic manipulation to add a marker to a particular chromosome in the germline
C)examining a trait that is the genotype AA or aa in all of the available parental stocks
D)DNA sequence analysis
E)protein sequencing

Question 33

You mate a squash with the genotype AAbb with a squash with the genotype aaBB. The resulting F1 squash are all AaBb. After mating two F1 squash, you obtain a F2 generation of squash as follows: Are A and B linked? Why or why not?

Question 34

Homologous chromosomes are held together in the

A)nucleus.
B)synaptonemal complex.
C)centromere.
D)MTOC.
E)kinetochore.

Question 35

The phases of meiosis that most resemble those of mitosis are

A)the meiosis II phases.
B)meiosis I, except for the pairing of homologs.
C)meiosis II, except for the pairing of homologs.
D)the meiosis I phases.
E)both A and B