Embibe Experts Solutions for Chapter: Cell Cycle and Cell Division, Exercise 1: TS EAMCET 2020 (28-Sep Shift-1)

Gene ${\mathrm{P}}^{53}$ guards integrity of $\mathrm{DNA}$ and hence called 'Guardian Angel of Cell's genome'. It checks the integrity of $\mathrm{DNA}$ at

Choose the incorrect statements among the following.
A) Cells of the lining of the gut are replaced by mitotic division constantly
B) Formation of liquid endosperm takes place, if karyokinesis is not followed by cytokinesis
C) In telophase, the chromosomes reach the poles and condenses to form the chromatic network
D) In quiescent stage, the cell is metabolically inactive.

If onion root tip cell has $14$ chromosomes and DNA content as $2\mathrm{C},$ what are the number of chromosomes and DNA content during ${\mathrm{G}}_1, \mathrm{S}$ and ${\mathrm{G}}_2$ phases respectively?

Fill in the blanks
During metaphase, spindle fibres attach to ________.
Centromeres split and chromatids __________ during __________.

Arrange the following statements on meiosis in a correct sequence.
A) Terminalisation of chiasmata.
B) Dissolution of synaptonemal complex.
C) Homologous chromosome separation.
D) Appearance of recombination nodules.
E) Pairing of homologous chromosomes.
F) Disappearance of nuclear envelope.

Assertion $\left(\mathrm{A}\right):$ In crossing over, the exchange of genetic material between two homologous chromosomes occur during both mitotic and meiotic cell divisions.

Reason $\left(\mathrm{R}\right):$ The process of crossing over is only possible and is mediated by recombinase.

The correct answer is:

Match the changes which occur in the chromosomes during meiosis, with the different phases of prophase-I.

The correct answer is

Choose the correct statements among the following.
(A) The stage between two meiotic divisions is called interphase
(B) During zygotene, the pairing of homologous chromosomes and synapsis takes place.
(C) Initiation of mitotic spindle takes place during metaphase
(D) In animals, mitotic cell division takes place in diploid somatic cells and not in haploid cells