Prophase II

Q.

What is the DNA content of somatic cells in the G₂ phase if their meiotic outcome contains 20 picograms of DNA?

1. 80 pg

2. 160 pg

3. 40 pg

4. 20 pg

Q.

What is the difference between law of independent assortment and the law of segregation?

Q. 2n=16 in a primary spermatocyte whisch is in metaphase of first meiotic division. What shall be the total number of chromatids in each of the secondary spermatocyte?

Q. Distance between the genes and percentage of recombination shows

1. a direct relationship
2. an inverse relationship
3. a reciprocal relationship
4. no relationship

Q. How many of the following statements are correct?
Statement I: Recombination of genes is directly proportional to the strength of linkage.
Statement II: Recombination of genes is inversely proportional to the strength of linkage.
Statement III: More the distance between the two genes on a chromosome, less the strength of linkage.
Statement IV: More the distance between the two genes on a chromosome, more the strength of linkage.
Statement V: Recombination frequency is inversely proportional to the distance between the genes present on a chromosome.

1. Three
2. Four
3. Two
4. One

Q. Statement 1: The physical distance between two linked genes determines both the strength of linkage and frequency of crossing over between them.
Statement 2: Linked genes show a higher chance of inheritance together if the distance between them is longer.

Choose the correct option

1. Both the statements are correct
2. Statement 1 is correct and statement 2 is incorrect
3. Statement 1 is incorrect and statement 2 is correct
4. Both the statements are incorrect
   

Q. The recombination frequency between three genes X, Y and Z are as follows
X-Y = 5.5%, Y-Z = 3.5% and X-Z = 1.5%
Which of the following shows the correct order of the arrangement of these genes on the chromosome?

1. Z-X-Y
2. X-Y-Z
3. Y-X-Z
4. X-Z-Y

Q. Give difference between mitosis and meiosis on the basis of number of daughter cells produced.​

Q.

What happens to the four daughter cells after meiosis?

Q.

Assertion (A): Meiosis is also known as reduction division.
Reason (R): Meiosis involves formation of daughter cells with half the number of chromosomes than that of parent cell.

1. Both A and R are true and R is the correct explanation for A.

2. Both A and R are true and R is the not the correct explanation for A.

3. A is true and R is false.

4. A is false and R is true.

Q.

Lack of independent assortment of two genes A and B in fruit fly Drosophila is due to

1. Recombination

2. Repulsion

3. Crossing over

4. Linkage

Q. How many of the following statements are wrong?
Statement I: Strength of linkage is directly proportional to the recombination of genes.
Statement II: Recombination of genes is inversely proportional to the strength of linkage.
Statement III: More the distance between the two genes on a
chromosome, less will be the strength of linkage.
Statement IV: More the distance between the two genes on a
chromosome, more the strength of linkage.
Statement V: Recombination frequency is inversely proportional to the distance between the genes present on a chromosome.

1. Three
2. Four
3. Two
4. One

Q.

Crossing over leads to _____________.

Q.

How does linkage affect inheritance?

Q. If the four genes A, B, C and D are 5, 10 and 30 Map units away from each other respectively and arranged in the same manner in a chromosome, which two genes would likely show more recombination?

1. A and B
2. B and C
3. C and D
4. A and C

Q. Which of the following events do not usually occur between two genes closely located to each other on the same chromosome?

1. Recombination
2. Crossing over
3. Both a and b
4. Transmission to progeny together as a unit

Q.

How many chromatids of a chromosome do a centromere hold?

Q. Pick the correct option with respect to the linkage and recombination.

1. Tightly linked genes on the same chromosomes show a higher recombination frequency
2. Genes far apart on the same chromosome show very few recombinations
   
3. Genes loosely linked on the same chromosome show very few recombinations
4. Tightly linked genes on the same chromosome show very few recombinations
   

Q. What happens in interkinesis?

1. DNA replication
2. Chromosome duplication
3. Resting stage
4. Preparation of second meiotic division

Q. The quantity of DNA in a chromosome at metaphase is :

1. One in mitosis and two in meiosis
2. Two in mitosis and four in meiosis
3. Two each in meiosis and mitosis
4. Two in mitosis and one in meiosis

Q. Aneuploidy is characterized by

1. presence of three sets of chromosomes
2. presence of an extra copy of chromosome
3. absence of a copy of chromosome
4. both b and c

Q. Which of the following is true regarding female Drosophila?

1. It shows very low recombination
2. It shows very high recombination
3. It shows no recombination at all
4. Only parental combinations are observed

Q. Which of the following events is/are less likely to occur in case of genes located in proximity to each other on the same chromosome?

I. Linkage
II. Recombination
III. Crossing over
IV. Dominance

1. I and IV only
2. I, II, and III
3. II, III, and IV
4. II and III only

Q.

Fill in the blanks:

Meiosis I is also known as _____ division.

Q.

What is recombination of gene?

Q. Given below are assertion and reason. Point out if

1. (A)
2. (B)
3. (C)
4. (D)

Q. In which stage of meiotic division centromere divides?

1. Metaphase II
   
2. Anaphase II
3. Anaphase I
4. Both A and B
   

Q. What will be the content of DNA in a somatic cell at G${}_2$ if its meiotic products have 20 picogram of DNA?

1. 40 pg
2. 80 pg
3. 20 pg
4. 160 pg

Q.
Meiosis II is similar to mitosis in that

1. chromosome number is reduced
2. DNA replicates before the division
3. sister chromatids separate during anaphase
4. homologous chromosomes synapse

Q.

Down's syndrome is due to

1. Non-disjunction of chromosome

2. Sex-linked inheritance

3. Crossing over

4. Linkage