Test: The Root (NCERT) - NEET MCQ

• The root is covered at the end by a thimble like structure called root cap.
• Meristematic tissue helps in the growth of plants.
• Meristematic cells when mature form the so called permanent cells.
• Root hairs increase the surface area which helps in increasing the levels of water absorption.

Line in NCERT: "The root is covered at the apex by a thimble-like structure called the root cap."

• Roots undergo modifications to perform conduction of water and minerals.
• Prop roots help in anchoring banyan tree to the ground.
• Pneumatophores are present in Rhizopora that help them to respire easily.
• Tap roots in turnip and carrot store food in their roots.

Line in NCERT: "The roots in some plants get modified for storage of food, mechanical support and respiration."

Fasciculated fleshy roots are modified adventitious roots, in which swollen roots or root tubers occur in clusters from lower nodes of stem example, Dahlia and Asparagus. In Curcuma, nodulose roots are found where the swelling occur only near the tips.

Line in NCERT: "Generally, dicotyledonous plants have tap roots while monocotyledonous plants have fibrous roots."

Part  A is the root hair zone which represents the zone of differentiation or maturation. This is the most suitable part for anatomical studies of root because different types of primary tissues differentiate or mature in this region. Xylem, phloem, pericycle, endodermis, cortex and epilema are clearly visible in this region.

Line in NCERT: "The cells of this region are very small, thin-walled and with dense protoplasm. They divide repeatedly."

1. Aerial roots are a part of shoot system - This statement is incorrect. Aerial roots are specialized structures that come from the shoot system but are still considered roots, not shoots. They are used for support and sometimes for photosynthesis or absorbing moisture from the air, but they are not part of the shoot system.

2. The portion of a plant that grows above the soil is called shoot system - This is generally correct. The shoot system usually refers to the parts of the plant that are above ground.

3. Shoot system comprises leaves, branches, flowers, and fruits - This is correct. All these structures are part of the shoot system and are involved in the growth and reproductive processes of the plant.

4. The shoot system develops from the plumule - This is correct. In the embryonic stage of a seed, the plumule is the part that develops into the shoot system after germination.

Therefore, the incorrect statement about the shoot system is: Aerial roots are a part of shoot system.

Line in NCERT: "The portion above the ground forms the shoot system."

• Tap root grows deep into the soil.
• Fibrous root grows laterally in the soil.
• In tap root system, one primary root and more than one secondary root is present.
• Most of the dicotyledons adopt tap root system.

Line in NCERT: "In majority of the dicotyledonous plants, the direct elongation of the radicle leads to the formation of primary root which grows inside the soil. It bears lateral roots of several orders that are referred to as secondary, tertiary, etc. roots."

The root cap's primary function is to protect the apical meristem (growth tissue) at the root tip as the root pushes through the soil. It plays no direct role in water absorption primarily because: It has no root hairs. Root hairs, which are extensions of root epidermal cells, are key structures in water and nutrient absorption from the soil. They are not found on the root cap but rather in the zone of maturation, which is located behind the zone of elongation and the root cap.

Given figure is of fasciculated root, which is the modified adventitious root that stores food material.

The zone of maturation has very fine thread-like structures known as root hair. These help in the absorption of water and minerals from the soil.

Line in NCERT: "From this region some of the epidermal cells form very fine and delicate, thread-like structures called root hairs."

The zone of elongation is a region located behind the root tip, where the newly formed cells from the root apical meristem undergo rapid elongation. In this region, the cells elongate and increase in length, pushing the root tip forward and causing the root to grow in length.

Line in NCERT: "The cells proximal to this region undergo rapid elongation and enlargement and are responsible for the growth of the root in length. This region is called the region of elongation."