Artificial Chromosome Doubling Can Be Induced by Means of Chemicals

question 110

Multiple Choice

Artificial chromosome doubling can be induced by means of chemicals that prevent the spindle from forming or functioning normally. A certain species of grass has seven pairs of chromosomes. How many chromosomes are present after one round of artificial chromosome doubling? After two rounds of chromosome doubling?

• A)14; 21
• B)14; 28
• C)21; 28
• D)28; 42
• E)28; 56

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Definitions:

Guard Cells

Pairs of cells surrounding stomata in plant leaves and stems, regulating gas exchange and water loss by controlling the opening and closing of stomata.

Epidermis

The outermost layer of cells covering an organism, particularly the surface epithelium of the skin or outer layer of leaves and other plant organs.

Parenchyma

A type of living plant tissue consisting of relatively unspecialized cells with thin cell walls that function in photosynthesis, storage, and as the site of many metabolic processes.

Tracheids

Tracheids are elongated cells in the xylem of vascular plants that serve in transport and structural support, facilitating the flow of water.