University of South Florida PCB 3063 Quiz 7 1)The long and short arm of a chromosome are called x and y, respectively y and x, respectively p and q, respectively   q and p, respectively tally and tiny, respectively   2

University of South Florida

PCB 3063

Quiz 7

1)The long and short arm of a chromosome are called x and y, respectively

y and x, respectively p and q, respectively

  q and p, respectively

tally and tiny, respectively

 

2. Crossing over involves the genetic exchange between

  non-sister chromatids of homologous chromosomes

non-sister chromatids of non-homologous chromosomes

 sister chromatids of homologous chromosomes

sister chromatids of non-homologous chromosomes

 

3. When do the sister chromatids separate during meiosis?

in metaphase I

in anaphase I in metaphase II

  in anaphase II

the sister chromatids separate in mitosis but not meiosis

 

4. The spindle fibers are attached to the centromere at the chromatin

aster

  kinetochore

telomere centriole

 

5. Which of the following events occurs in meiosis but NOT mitosis?

 chromatid formation

spindle formation

 

chromosome condensation

  chromosome pairing

chromosome movement to poles

 

6. Immediately following anaphase of mitosis, a cell would have half as many chromosomes as it did before anaphase.

half as much DNA as it did before anaphase.

  twice as many chromosomes as it did before anaphase.

twice as much DNA as it did before anaphase.

both C and D

 

7. Consider a diploid organism that has 3 pairs of chromosomes. Assuming no crossing-over occurs, what proportion of gametes would be expected to contain chromosomes of maternal origin only?

1/4

1/2

  1/8 1/16

none of these choices

 

8. Consider a diploid organism that has 3 pairs of chromosomes. Assuming no crossing-over occurs, what proportion of gametes would be expected to contain some chromosomes from both paternal and maternal origin?

1/4

1/2

  3/4 5/8

none of these wonderful choices

 

9. A cell contains 18 pairs of chromosomes immediately after completion of mitotic cytokinesis. How many chromatids were present in metaphase?

9

18

27

36

  72

 

10. Chiasmata are formed during

  Prophase I

Metaphase

 I Anaphase I

Prophase II

 Anaphase II

 

 

11. An acrocentric chromosome has

a p and a q arm that are equal in size two centromeres

no centromeres

a p arm that is larger than the q arm in size

  none of these choices

 

12. Homologous chromosomes separate during anaphase of mitosis

  anaphase I of meiosis

anaphase II of meiosis

two of the above

none of the above

 

13. In humans, how many tetrads are present in metaphase I of meiosis?

 2

  23

 46

92

 

14. The newly-discovered organism Yawle nhoj, has a diploid chromosome number of 56. How many bivalents and tetrads would be expected to form during meiosis?

  28 and 28, respectively

56 and 28, respectively

56 and 56, respectively

112 and 56, respectively

none of these choices

 

15. The newly-discovered organism Yawle nhoj, has a diploid chromosome number of 56. Suppose that one of the chromosome pairs fails to disjoin properly during Meiosis I. How many chromosomes will be present in each of the four gametes that result from that meiosis? Assume meiosis II is normal.

12, 12, 16, 16

12, 16, 14, 14

28, 28, 0, 0

28, 0, 14, 14

  none of the above

 

16. A cell contains 20 chromosomes immediately after completion of telophase of meiosis II. How many chromatids were present in metaphase I?

10

20

 

40

  80

none of these choices

 

17. What is the correct order for the stages of the cell cycle? G1-G2-M-S

  G1-S-G2-M

M-G1-G2-S

G1-M-G2-S

G1-G2-S-M

 

18. The end results of meiosis is the formation of two genetically identical cells.

two genetically different cells.

four genetically identical cells.

  four genetically different cells.

 

19. Which of the following best describes the chromosomal composition of a daughter cell immediately following telophase I of meiosis?

haploid, and each chromosome consists of a single chromatid

  haploid, and each chromosome consists of two chromatids

diploid, and each chromosome consists of a single chromatid diploid, and each chromosome consists of two chromatids

none of the above

 

20. Mendel’s second law (independent assortment) can be explained by the separation of chromatids during anaphase II of meiosis

the crossing over between homologous chromosomes during prophase I of meiosis

  the random arrangement of homologous chromosomes at metaphase I of meiosis

 the random arrangement of genes on a chromosome

the separation of chromatids during anaphase of mitosis

 

21. In a human, how many different types of gametes are possible? Assume no crossing-over.

23

46

2 x 23

23 x 23

  2^23

 

22. In mitosis, chromosomes consist of two chromatids from G1 of interphase through metaphase.

G1 of interphase through anaphase.

  G2 of interphase through metaphase.

 

G2 of interphase through anaphase.

S of interphase through prophase.

 

23. Assume the amount of DNA in a cell immediately following mitotic cytokinesis is C. The amount of DNA during G1 of interphase would be

  C.

2C

4C

C/2 C/4

 

24. In a particular animal, lung cells have 32 pairs of chromosomes. How many chromosomes does a sperm cell contain?

64

32

16

8

4

 

25. The five sub-stages of prophase I are, in order,

diplonema, zygonema, pachynema, leptonema, diakinesis leptonema,

pachynema, zygonema, diplonema, diakinesis leptonema, zygonema,

 pachynema, diakinesis, diplonema zygonema, diplonema, pachynema, leptonema, diakinesis

  leptonema, zygonema, pachynema, diplonema, diakinesis

 

26. In an animal with 2n = 24, what is the total number of chromatids present at prophase I of meiosis?

12

24

  48

 96

none of these choices

 

27. In a plant with 2n = 40, what is the total number of chromatids present at prophase of mitosis? 10

20

40

  80

none of these choices

 

28. Mitosis is used for

asexual reproduction in unicellular organisms

 

growth and repair in multicellular organisms production of gametes in multicellular organisms

  two of the above

all of the above

 

29. The synaptonemal complex is the nucleoprotein complex that makes up a chromosome

makes up the spindle fibers

  holds homologous chromosomes together during meiosis

holds sister chromatids together during meiosis

 

30. The events of meiosis II are most similar to meiosis I

  Mitosis

 Interphase

 interkinesis

 

31. Meiosis I is called the

  reductional division.

equational division.

multiplicational division.

recombinational division.

“no name” division.

 

32. In humans, how many chromosomes are present in metaphase II of meiosis?

2

  23

46

92

 

33. Drosophila melanogaster has 2n = 8. How many bivalents are present in prophase I of meiosis?

 1

2

  4

8

16

 

34. The housefly, Musca domestica, has 2n =12. A fly would have             chromosomes in metaphase of mitosis; sister chromatids in metaphase I meiosis and                  chromosomes in prophase II of meiosis.

24; 24; 12

  12; 24; 6

12; 12; 12

 

24; 12; 6

12; 12; 6

 

35. The organism Sllub adirolfhtuos has 16 pairs of long chromosomes, whereas the organism Scub yabapmat has 20 pairs of short chromosomes. The expected chromosome number in somatic tissues of a hybrid between these two organisms is

18

28

36

56

72

 

 

36. The G0 phase occurs before G1.

 

  between G1 and S.

 between S and G2.

 between G2 and M.

in prophase.

 

37. The DNA in G1 is found as chromosomes.

  chromatin.

chromatids.

 chromamia.

 

38. Which of the following terms is NOT used to describe the position of the centromere in eukaryotic chromosomes?

submetacentric t

elocentric

  anticentric

metacentric

 

39. A locus is

an alternative form of a gene.

the point of formation of spindle fibers.

the point of attachment of spindle fibers.

 

  the position of a gene on a chromosome.

the position of a chromosome during metaphase.