Cell Cycle and Cell Division — Page 4 | NEET Biology

Q31

Microtubule is involved in the

A cell division

B muscle contraction

C membrane architecture

D DNA recognition

Correct Answer

Option A

Solution

(a) The spindle fibres involved in cell division are made of microtubules.

Q32

During cell division, the spindle fibres attach to the chromosome at a region called

A chromocentre

B kinetochore

C centriole

D chromomere

Correct Answer

Option B

Solution

(b) Kinetochore is the proteinaceous covering of centromere, to which spindle fibers attach.

Q33

If you are provided with root-tips of onion and asked to count the chromosomes, which stage is most convenient?

A Metaphase

B Telophase

C Anaphase

D Prophase

Correct Answer

Option A

Solution

(a) Chromosomes are most distinct in the metaphase stage.

Q34

Synapsis occurs between:

A mRNA and ribosomes

B spindle fibres and centromere

C two homologous chromosomes

D a male and a female gamete

Correct Answer

Option C

Solution

(c) Synapsis is the pairing of two homologous chromosomes that occurs during prophase I of meiosis.

Q35

At metaphase, chromosomes are attached to the spindle fibres by their:

A satellites

B secondary constrictions

C kinetochores

D centromere

Correct Answer

Option C

Solution

(c) Kinetochores are large protein complexes that bind centromeres of chromosomes to microtubules of mitotic spindle fibres.

Q36

The complex formed by a pair of synapsed homologous chromosomes is called

A Kinetochore

B Bivalent

C Axoneme

D Equatorial plate

Correct Answer

Option B

Solution

(b) The complex formed by a pair of synapsed homologous chromosomes is called a bivalent or a tetrad.

Q37

Which of the following is not a characteristic feature during mitosis in somatic cells?

A Spindle fibres

B Disappearance of nucleolus

C Chromosome movement

D Synapsis

Correct Answer

Option D

Solution

(d) Synapsis is the pairing of homologous chromosomes that occurs during meiosis, not mitosis.

Q38

Spindle fibres attach on to

A Telomere of the chromosome

B Kinetochore of the chromosome

C Centromere of the chromosome

D Kinetosome of the chromosome

Correct Answer

Option B

Solution

(b) Attachment of microtubules to chromosomes is mediated by kinetochores.

Q39

Which of the following options gives the correct sequence of events during mitosis?

A Condensation nuclear membrane disassembly arrangement at equator centromere division segregation telophase

B Condensation crossing over nuclear membrane disassembly segregation telophase

C Condensation arrangement at equator centromere division segregation telophase

D Condensation nuclear membrane disassembly crossing over segregation telophase

Correct Answer

Option A

Solution

(a) Correct sequence: DNA condensation, disassembly of nuclear membrane, chromosomes align at equator, centromere division, segregation, telophase.

Q40

Dissolution of the synaptonemal complex occurs during

A Zygotene

B Diplotene

C Leptotene

D Pachytene

Correct Answer

Option B

Solution

(b) Dissolution of the synaptonemal complex occurs during diplotene stage of Prophase-I of Meiosis-I.