Astral rays arise from
Number of mitotic division required in a cell of root tip for formation of 128 cells is
Barr body is found in the cytoplasm during
(a) interphase in cell of female mammal.
(b) interphase in cell of male mammal.
(c) prophase in cell of female mammal.
(d) prophase in cell of male mammal.
When synapsis is complete all along the chromosome, the cell is said to have entered a stage called
Many cells function properly and divide mitotically even though they do not have
(a) Plasma membrane
Which of the following is not a characteristic of meiosis?
(a) It involves two stages of DNA replication one before meiosis-I and another before meiosis-II
(b) It involves recombination and crossing over
(c) Sister chromatids separate during anaphase- II
(d) Nuclear membrane disappears during prophase.
Microtubule depolymerizing drug such as colchicine is expected to
(a) inhibit spindle formation during mitosis
(b) inhibit cytokinesis
(c) allow mitosis beyond metaphase
(d) induce formation of multiple contractile
Which of the following statements is incorrect about G0 phase.
(a) Mitosis occurs after G0 phase.
(b) Biocatalysts can be used to exit G0 phase.
(c) Cell volume keeps on increasing during this phase.
(d) Cell metabolism occurs continuously in G0 phase.
Beads on string like structures of A are seen in B, which further condense to form chromosomes in C stage of cell division.
A B C
(a) Chromonema Chromatin Metaphase
(b) Chromatin Chromatid Metaphase
(c) Chromonema Chromosome Anaphase
(d) Chromonema Chromatid Anaphase.
In a diploid cell, at which stage of cell cycle, the amount of DNA is doubled?
(a) G1 and G2 phase
(b) G0 phase
(c) S, G2 and M phase
(d) S phase