FREE NEET Biology Practice MCQ Test: Cell Cycle And Cell Division Exercise 1 Questions Answers With Detailed Explanations [PDF]

Answer: (a)

Each chromosome composed of one chromatid in Anaphase-II.

Answer: (a)

Synapsis is the pairing of two homologous chromosomes during meiosis. It allows matching-up of homologous pairs prior to their segregation, and possible chromosomal crossover between them. The process of attachment of homologous chromosomes leads to the formation of bivalents. These two events occur in zygotene stage of prophase I.

Answer: (b)

The mitotic spindle forms and the nuclear membrane disperses during prophase.

Answer: (b)

Answer: (b)

Answer: (a)

$G_{1}$ phase means gap 1 phase. It is the interval between mitosis and initiation of DNA replication. The cell is metabolically active and grows continuously but the DNA does not replicate. The cell also synthesizes proteins that are required for DNA replication.

Answer: (b)

Answer: (d)

Answer: (d)

The points of attachment between homologous chromosomes after their separation in diplotene appear X-shaped. They are called chiasmata.

Answer: (c)

Answer: (c)

Anaphase is characterized by splitting of the centromeres and separation of chromatids. Chromatids move to opposite poles from the equatorial plates.

Answer: (b)

A – II, B – III, C – IV, D – I

Anaphase – Movements of chromatids towards opposite poles.

Prophase – Initiation of assembly of mitotic spindle.

Interphase – Proteins are synthesized in preparation for mitosis while cell growth continues.

Metaphase – Spindle fibres attach to the kinetochores of chromosomes.

Answer: (b)

Answer: (b)

Pairs A and B are correctly matched. Diplotene – Chiasmata Meiosis – Haploid cells

Answer: (a)

During zygotene, a substage of Prophase I of meiosis I, chromosomes start pairing together called synapsis. Such paired chromosomes are called as homologous chromosomes. A complex structure i.e., synaptonemal complex is formed by a pair of synapsed homologous chromosomes called a bivalent or a tetrad.

Answer: (b)

Answer: (c)

Answer: (b)

Colchicine is an alkaloid derived from the autumn crocus, Colchicum autumnale. It inhibits spindle formation in cells during mitosis so that chromosomes cannot separate during anaphase, thus inducing multiple sets of chromosomes. Colchicine is used in genetics, cytology, and plant breeding research and also in cancer therapy to inhibit cell division.

Answer: (c)

Answer: (d)