Deck 2: Mitosis and Meiosis

Question 1

Name two cellular organelles,each having genetic material,that are involved in either photosynthesis or respiration.

Answer 1

chloroplasts and mitochondria

Question 2

How many haploid sets of chromosomes are present in a diploid individual cell with a chromosome number of 46? 32?

Answer 2

2; 2

Question 3

Which type of cell structure is the nucleolus organizer (NOR)responsible for producing?

Answer 3

ribosome

Question 4

The ant Myrmecia pilosula is found in Australia and is named bulldog because of its aggressive behavior.It is particularly interesting because it carries all its genetic information in a single pair of chromosomes.In other words,2n = 2.(Males are haploid and have just one chromosome.)Which of the following figures would most likely represent a correct configuration of chromosomes in a metaphase I cell of a female?

A)A
B)B
C)C
D)D
E)E

Question 5

If a typical somatic cell has 64 chromosomes,how many chromosomes are expected in each gamete of that organism?

A)8
B)16
C)32
D)64
E)128

Question 6

An interesting group of ants consists of several virtually identical,closely related species,with females having chromosome numbers of 18,20,32,48,60,62,and 64.If one crossed a female of species (A)with 32 chromosomes and a male species (B)with 9 chromosomes (males are haploid,and each gamete contains the n complement),how many chromosomes would one expect in the body (somatic)cells of the female offspring?

A)4)5
B)9
C)25
D)32
E)41

Question 7

How many haploid sets of chromosomes are present in an individual cell that is tetraploid (4n)?

Question 8

List four terms used to describe the normal morphologies,with respect to arm ratio,of eukaryotic chromosomes.

Question 9

In which stage of the cell cycle is G0 located?

Question 10

The house fly,Musca domestica,has a haploid chromosome number of 6.How many chromatids should be present in a diploid,somatic,metaphase cell?

Question 11

In an organism with 52 chromosomes,how many bivalents would be expected to form during meiosis?

A)13
B)26
C)52
D)104
E)208

Question 12

Homologous chromosomes can be matched by their similar structure and function within a nucleus.Which chromosomes making up a genome do not follow the same characteristics of homology?

Question 13

After which meiotic stage (meiosis I or II)would one expect monads to be formed?

Question 14

In a healthy male,how many sperm cells would be expected to form from (a)400 primary spermatocytes? (b)400 secondary spermatocytes?

A)(a)800; (b)800
B)(a)1600; (b)1600
C)(a)1600; (b)800
D)(a)400; (b)400
E)(a)100; (b)800

Question 15

When cells withdraw from the continuous cell cycle and enter a "quiescent" phase,which stage are they said to be in?

Question 16

What is the outcome of synapsis,a significant event in meiosis?

A)side-by-side alignment of nonhomologous chromosomes
B)dyad formation
C)monad movement to opposite poles
D)side-by-side alignment of homologous chromosomes
E)chiasma segregation

Question 17

Regarding the mitotic cell cycle,what is meant by a checkpoint?

Question 18

During interphase of the cell cycle,________.

A)DNA recombines
B)sister chromatids move to opposite poles
C)the nuclear membrane disappears
D)RNA replicates
E)DNA content essentially doubles

Question 19

For the purposes of this question,assume that a G1 somatic cell nucleus in a female Myrmecia pilosula contains 2 picograms of DNA.How much DNA would be expected in a metaphase I cell of a female?

A)16 picograms
B)32 picograms
C)8 picograms
D)4 picograms
E)Not enough information is provided to answer the question.

Question 20

In a healthy female,how many secondary oocytes would be expected to form from 100 primary oocytes? How many first polar bodies would be expected from 100 primary oocytes?

A)200; 50
B)100; 50
C)200; 300
D)100; 100
E)50; 50

Question 21

There is about as much nuclear DNA in a primary spermatocyte as in ________ (how many)spermatids?

Question 22

If a typical G1 nucleus contains 2C (two complements)of DNA,a gamete that is haploid (n)contains 1C of DNA.

Question 23

Assume that an organism has a diploid chromosome number of 6.Two chromosomal pairs are telocentric,and the other pair is metacentric.Assume that the sex chromosomes are morphologically identical.Draw chromosomes as you would expect them to appear at the following stages:
primary oocyte (metaphase)
secondary spermatocyte (metaphase)
first polar body (metaphase)

Question 24

Assume that the somatic cells of a male contain one pair of homologous chromosomes (e.g.,A?Ab)and an additional chromosome without a homolog (e.g.,W).Which chromosomal combinations would be expected in the meiotic products (spermatids)of a single primary spermatocyte? (There may be more than one answer.)

Question 25

The horse (Equus caballus)has 32 pairs of chromosomes,whereas the donkey (Equus asinus)has 31 pairs of chromosomes.How many chromosomes would be expected in the somatic tissue of a mule?

Question 26

List,in order of appearance,all the cell types expected to be formed during (a)spermatogenesis and (b)oogenesis.

Question 27

Down syndrome,or trisomy 21,in humans is caused by an extra copy of the relatively small,acrocentric 21.Including only chromosome 21,the X chromosome (medium in size and somewhat metacentric),and the Y chromosome (small and acrocentric),draw one possible array of chromosomes in the four sperm cells produced by the complete meiosis of one primary spermatocyte.For the purposes of this question,assume that males with Down syndrome produce normal ratios of sperm cells.(More than one answer is possible.)

Question 28

List in order of occurrence the phases of mitosis.

Question 29

Name two evolutionarily significant benefits of meiosis that are not present in mitosis.

Question 30

What is meant by the term chiasma?

Question 31

If a typical G1 nucleus is 2n and contains 2C (two complements)of DNA,a prophase I cell is 2n and contains 4C of DNA.

Question 32

A chromosome may contain one or two chromatids in different phases of the mitotic or meiotic cell cycle.

Question 33

Trisomy 21 or Down syndrome occurs when there is a normal diploid chromosomal complement of 46 chromosomes plus one (extra)chromosome 21.Such individuals therefore have 47 chromosomes.Assume that a mating occurs between a female with Down syndrome and a normal 46-chromosome male.What proportion of the offspring would be expected to have Down syndrome? Justify your answer.

Question 34

You may have heard through various media of an animal alleged to be the hybrid of a rabbit and a cat.Given that the cat (Felis domesticus)has a diploid chromosome number of 38 and a rabbit (Oryctolagus cuniculus)has a diploid chromosome number of 44,what would be the expected chromosome number in the somatic tissues of this alleged hybrid?

Question 35

Drosophila melanogaster,the fruit fly,has a 2n chromosome number of 8.Assume that you are microscopically examining the mitotic and meiotic cells of this organism.You note that in the female,two chromosomal pairs are metacentric and two pairs are acrocentric.
(a)Draw the chromosomal configurations as you would expect to see them at the stages listed:
mitotic metaphase first polar body (metaphase)
primary oocyte (metaphase) ootid (G1)
secondary oocyte (metaphase)
(b)Given that the previously mentioned cells are from individuals heterozygous for two independently segregating,autosomal loci,plum eyes and curled wings,place appropriate symbols (of your designation)on chromosomes in the drawings you made for part (a).Assume no crossing over,and there may be more than one correct answer in some cases.
(c)Assuming that a somatic G2 nucleus from the individuals mentioned above contains about 8.0 picograms of DNA,how much nuclear DNA would you expect in each of the cells mentioned in part (a)?

Question 36

S phase is the part of interphase when DNA duplication takes place.

Question 37

Normal diploid somatic (body)cells of the mosquito Culex pipiens contain six chromosomes.Assign the symbols A^mA^p,B^mB^p,and C^mC^p to the three homologous chromosomal pairs.The "m" superscript indicates that the homolog is maternally derived; the "p" indicates a paternally derived homolog.Assume that in the genus Culex,the sex chromosomes are morphologically identical.

Question 38

The centromere of a chromosome separates during anaphase.

Question 39

The accompanying sketch depicts a cell from an organism in which 2n = 2 and each chromosome is metacentric.
(a)Circle the correct stage for the cell in this sketch:

anaphase of mitosis
anaphase of meiosis I
anaphase of meiosis II
telophase of mitosis
(b)Given that each G1 nucleus from this organism contains 16 picograms of DNA,how many picograms of chromosomal DNA would you expect in the cell shown here?

Question 40

The two terms reductional and equational generally refer to which stages of meiosis (I or II)?

Question 41

The meiotic cell cycle involves two cell divisions but only one DNA replication.

Question 42

An organism with a diploid chromosome number of 46 will produce 2²³ combinations of chromosomes at the end of meiosis.

Question 43

During meiosis,chromosome number reduction takes place in anaphase II.

Question 44

An organism with a haploid number of 10 will produce 1024 combinations of chromosomes at the end of meiosis.

Question 45

A bivalent at pachytene contains four chromatids.