What is true of the ROOT APICAL MERISTEM?
a. It contains the large amyloplasts that sense gravity
b. It contains cells that are elongating
c. It is protected by the Root Cap
d. a and c
e. all of the above
The correct answer and explanation is:
The correct answer is e. all of the above.
The root apical meristem (RAM) is located at the tip of the growing root and plays a vital role in the growth and development of the root. Let’s break down the options to understand why this is the correct answer:
a. It contains the large amyloplasts that sense gravity
The root apical meristem contains amyloplasts, which are specialized plastids that store starch. These amyloplasts help in the process of gravitropism, which is the plant’s ability to sense and respond to gravity. When gravity affects the root, the amyloplasts move within the cells, helping the root to grow downward. This ensures that roots grow in the direction of gravity, anchoring the plant and allowing it to obtain water and nutrients from the soil.
b. It contains cells that are elongating
The root apical meristem contains cells that are actively dividing and elongating. These cells are constantly pushing the root tip downward as the root grows. The elongation of these cells behind the meristem allows the root to extend deeper into the soil. As the cells mature, they differentiate into various types of tissues, such as the epidermis, cortex, and vascular tissue.
c. It is protected by the Root Cap
The root apical meristem is protected by a structure called the root cap. The root cap is a protective layer of cells that covers the tip of the root, shielding the delicate meristematic cells from mechanical damage as the root pushes through the soil. The root cap also plays a role in sensing gravity, which aids in the directional growth of the root. It is constantly replenished as cells are sloughed off during the root’s growth.
Given all these functions, the root apical meristem is crucial for the root’s growth, protection, and ability to sense and respond to environmental cues. Therefore, all the provided statements are correct.