Question

Identify the correct order from proximal to distal region of root

Answer 1

Answer:

Hello

Explanation:

The root tip can be divided into three zones: a zone of cell division, a zone of elongation, and a zone of maturation and differentiation ((Figure)). The zone of cell division is closest to the root tip; it is made up of the actively dividing cells of the root meristem.

Answer 2

Answer:

If we move from the proximal to the distal end of the root- the Region or zone of maturation comes first, then the region of elongation followed by the region of cell division, and at last tip of the root is covered by the root cap.

Explanation:

1. Region of Maturation- consists of root hairs, also called root hair zone. Narrow trichomes are the most common type of root hairs and can be seen extending out from this region. They are made of epidermal cells.

• Root hairs increase the surface area for absorption of minerals and water.

• Above this zone, at the extreme proximal end, there is a region where new lateral roots emerge.

2. Region of elongation- It is located just above the root cap and root apical meristem. It is only a few millimeters long and the cells in this region are specialized to undergo cell division and cells expand enormously.

• Outermost cells are protoderm and forms epidermis and in the center, there is provascular tissue that forms the primary xylem and phloem.
• Parenchyma is present between the protoderm and provascular tissue which develops in the root cortex.

• Tissues are very permeable here and minerals can diffuse deep into the root through apoplast.

3. Region of cell division- It consists of Apical meristem which is further covered by the root cap.

• Apical meristem produces cells regularly which are later extended into mature root tissue.

• It contains a center called the quiescent center which is initially an inactive central region, it is a reserve of healthy cells as it gets activated only if the part of the apical meristem or the root cap is damaged and helps by forming a new apical meristem. A new quiescent center is formed in the new apical meristem when the central cells become inactive again.

The root cap is the distal-most point of the root. Root cap secretes mucigel( complex polysaccharide) that helps in lubricating the passage of the root through the soil when it grows deeper in the soil.