Question

Which of the following statements is CORRECT?

Select one:

a. The first meiotic division results in the segregation of sister chromatids into daughter cells.

b. Polar bodies are only observed in male meiotic divisions.

c. The second meiotic division results in a reduction in chromosome number from diploid to haploid.

d. In females, the cytoplasm is divided unequally amongst the four daughter cells after meiosis II.

If the cyclins that control the transition between S & G2 phase have been inactivated. Which of the following scenarios would be the MOST LIKELY result?

Select one:

a. Cells would enter M phase where errors in DNA replication will be corrected.

b. Cells would progress through the rest of the cell cycle without any problems.

c. Cells would enter M phase containing errors following DNA replication that will not be corrected.

d. Cells would not enter M phase at all and would be pushed into G0 phase.

Two genes are required for the determination of hair colour in guinea pigs:
i. One for the production of the coloured pigment (where P encodes black pigment which is dominant over p for grey pigment)
ii. Another gene is required for the fixation of the pigment to the strand of hair (where F is dominant and fixes the hair pigment, while f is recessive and does not fix the hair pigment).

Therefore, the F gene is epistatic to the P gene. In an individual who is albino (i.e. has no hair colour at all), which of the following genotypes is MOST LIKELY?

Select one:

a. ppFf

b. PPFF

c. PpFf

d. Ppff

A mating between two parents, both with blood type AB, will result in progeny with which of the following blood types?

Select one:

a. 50% A; 25% B; 25% AB

b. 25% A; 25% B; 50% AB

c. 100% AB

d. 25% A; 50% B; 25% AB

Answer 1

Answer:

d. In females, the cytoplasm is divided unequally amongst the four daughter cells after meiosis II.

Explanation:

The first meiotic division results in a reduction in chromosome number from diploid to haploid.

The second meiotic division results in the segregation of sister chromatids into daughter cells.

The one egg cell that results from meiosis contains most of the cytoplasm, nutrients, and organelles. The unequal distribution of the cytoplasm during oogenesis is necessary as the zygote that results from fertilization receives all of its cytoplasm from the egg. So the egg needs to have as much cytoplasm as possible

2). d. Cells would not enter M phase at all and would be pushed into G0 phase.

Explanation:

If any probles arises during the stage, the cell cycle moves to G0 phase to get repaired.

3). D). Ppff

Explanation:

P_F_ = Black

ppF_ = grey

P_ff or ppff = albino

4). b. 25% A; 25% B; 50% AB

Explaantion:

IAIB x IAIB –Parents

	IA	IB
IA	IAIA (type A)	IAIB (type B)
IB	IAIB (type AB)	IBIB (type B)

Type A = 25%, Type B = 25% & Type AB = 50%