Page 52 - Biology - XII

Q8. Cell plate formation in dividing plant cells is formed by
(a) products of Golgi complex (b) microtubules

(c) both (a) and (b) (d) none of these
Q9. The phase after cytokinesis is
(a) S-phase (b) G -phase (c) M-phase (d) G -phase
1
2
Q10. The pairing of chromosomes (bivalents) takes place in
(a) pachytene of meiosis I (b) zygotene of meiosis I
(c) pachytene of meiosis II (d) zygotene of meiosis II

Q11. Which of the following traits seen in Pachytene of meiosis?
(a) Chiasmata (b) Crossing over (c) Tetrad (d) All of these

Q12. Answer the following based on the fi gure shown below.

2n

Mention the number of divisions required to get half the chromosome number.

(a) one (b) two (c) three (d) four

Q13. The four phases of mitotic cell division are included in
(a) S-phase (b) G -phase (c) G -phase (d) M-phase
1 2
Q14. Cytokinesis takes place during
(a) telophase (b) anaphase (c) metaphase (d) prophase

Answer key

1. (b), 2. (c), 3. (d), 4. (a), 5. (b), 6. (c), 7. (d), 8. (c), 9. (d), 10. (b), 11. (d), 12. (c), 13. (d), 14. (a)

Assertion-Reason Type Questions

These consist of two statements—Assertion (A) and Reason (R). Answer these questions by selecting
the appropriate option given below:
a. Both A and R are true and R is the correct explanation of A.
b. Both A and R are true, but R is not the correct explanation of A.

c. A is true, but R is false. d. A is false, but R is true.
1. Assertion (A) : Mitosis is known as equational division.
Reason (R) : During gamete formation, mitosis leads to formation of haploid cells of diff erent
shape.

Answer key
1. (c)

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