Chromosome Kit: 27 MCQs with answers

W.S. Sutton and T. Boveri

The source states that in 1902, W.S. Sutton and T. Boveri suggested that chromosomes were the physical structures which act as messenger of heredity.

Metaphase

The source mentions that after specific staining, chromosomes can be clearly seen during mitotic cell division particularly during the metaphase.

Homologues

The source defines the two chromosomes that form a pair as homologues.

46

The source states that each cell in every human being has 46 chromosomes consisting of 23 different pairs.

Haploid

The source defines a single set of chromosomes found in a mature egg or spermatozoa as a haploid set, denoted by n.

One X and one Y chromosome

The source states that in the XX-XY system, males have one X chromosome and a reduced size Y chromosome.

Chromatin

The source states that the material of chromosomes is called chromatin.

True

The source states that in all eukaryotic organisms including fishes, the DNA molecules in the nucleus are combined into proteins, mainly histones, to make chromosomes.

DNA and histone proteins

Chromosomes are made of highly coiled DNA combined with histone proteins.

In pairs

Chromosomes occur in pairs in diploid organisms.

It reduces by half

Meiosis reduces the chromosome number by half to form haploid gametes.

It restores the diploid number

Fertilization restores the diploid number of chromosomes.

By centromere position

Chromosomes are classified by their centromere position.

They are darkly stained bodies

Chromosomes are darkly stained, small bodies in the nucleus.

To determine the mechanism of inheritance

Chromosomes determine the mechanism of inheritance.

The number, size, and shape of chromosomes

The number, size, and shape of chromosomes vary by species.

Diploid

Diploid refers to the condition when a cell has two sets of chromosomes.

Gene

A gene is the basic unit of heredity that is carried by chromosomes.

Metacentric

The source describes metacentric chromosomes as having the centromere located approximately at the centre, with arms approximately equal, appearing U or V shaped during movement.

Acrocentric or telocentric

The source states that acrocentric or telocentric chromosomes, where the centromere is located at the end, are the most common karyotypes among fish species.

Maintain the integrity of chromosome threads

The source states that telomeres are stable entities, usually heterochromatic, and are for maintaining the integrity of chromosomes threads.

Polyploidy

The source defines polyploidy as the condition when more than two sets of chromosomes occur in cells.

Euchromatin

The source states that euchromatin is believed to contain the genes in a linear array like beads on a string.

It is reduced to one half

The source states that meiosis involves reduction of the number of chromosomes to one half, and each gamete receives half as many chromosomes as those contained in the cells of the parent.

True

The source states that heterochromatin is regarded as genetically inert and to have a function in maintaining the structural integrity of the chromosome and perhaps regulating gene expression.

Ribosome

The source describes chromosomes as consisting of a limiting membrane called pellicle, an amorphous matrix, and chromonema. Ribosomes are not mentioned as chromosome components.

Salmonids and catostomids

The source mentions that some rare species of fish are tetraploids, notably the salmonids and catostomids.