Practice MCQ Questions and answers on Biology-GK

A typical chromosome has two parts a centrifuge and Centrosome.

In unicellular eukaryotes, reproduction can occur by mitosis and cytokinesis—the other form of cell division.

Healing of wounds is dependent upon the mitotic division of underlying cells.

Chromatin is formed by a repeating nucleosome units, which are closely attached to each other to a continuous fibre.

The centromere is the part of a chromosome where the sister chromatids are linked together during the cell division. In mitosis, spindle fibres attach to the centromere via the kinetochore. Centromeres were first defined as genetic loci that direct the behaviour of chromosomes.

During anaphase, the “upward phase,” the cohesin proteins degrade, and the sister chromatids separate at the centromere. Each chromatid, now called a chromosome, is pulled rapidly toward the centrosome to which its microtubule is attached.

The shape of chromosome is clearly visible at metaphase.

At the end of mitosis, two daughter cells will be formed which are exact copies of the original cell. Each daughter cell will have 30 chromosomes.

Pollen development is a postmeiotic process that produces immature pollen grains from microspores. The maturation process can be dissected into various stages. During microspore mitosis, the pollen first develops a large vacuole that mediates nuclear migration to produce polarized cells.

Completion of meiosis II results in the production of four haploid daughter cells, each of which contains only one copy of each chromosome.