A mutant plant has roots that grow in all directions. Which of the following organelles would you expect to be missing in the cell?

mitochondria

amyloplast

chloroplast

nucleus

amyloplast

Explanation:

Amyloplasts are nonpigmented organelles specializing in synthesizing and storing starch granules formed by polymerization of the glucose molecule. They are found in plant cells of some plants, especially tubers and bulbs, such as potatoes. They are essential for plants as they serve to store stockpiles, as under stressful conditions amyloplasts can break down starch into sugars used to nourish the cell and plant tissues.

In addition to their function of storing reserve material, amyloplasts are also involved in the perception of the severity of plants (called gravitropism). In the terminal portion of the roots (hood) is a central region, the columella, filled with special cells, the statocysts. Within these, a large amount of amyloplasts, usually large in size and densely filled, can be found. These organelles move within the cytoplasm of the statocysts depending on the root growth position. If it grows downward, vertically and in favor of gravity, the amyloplasts concentrate at the base (lower portion) of the columella cells. If the root develops laterally in the soil in the horizontal position, the amyloplasts are positioned on the side of the cell. Thus, the root columella is said to act in the perception of the gravitational orientation (gravitropism) of the plant. If the plant has roots that grow in all directions, it means the plant has a mutation. This mutation was caused by the lack of amyloplast in the root cells.