Describe the structure and function of a root hair cell, identify the main parts of a plant root, and explain the roles of the endodermis, pericycle, and vascular tissues.

2.1 a) I cannot draw a diagram, but I can describe the structure of part 1, which is a root hair cell.
A root hair cell is an epidermal cell with a long, thin, finger-like extension. It has a thin cell wall, a large central vacuole, cytoplasm, and a nucleus.

2.1 b)
The function of this structure is the absorption of water and mineral salts from the soil.

2.2
The three main parts that plant roots consist of are:

• Epidermis (Layer 1)
• Cortex (Layers 2, 3, 4)
• Vascular Cylinder/Stele (Layer 9)

2.3
The layers or cell types that make up the cortex are:

• Parenchyma cells (Layers 2, 3, 4)

2.4 a)
The Casparian strips are found in layer 5 (the endodermis).

2.4 b)
Casparian strips are waxy, waterproof bands of suberin found in the radial and transverse cell walls of endodermal cells.

2.4 c)
A function of Casparian strips is to regulate the movement of water and dissolved minerals into the vascular cylinder, forcing them to pass through the cytoplasm of endodermal cells (symplast pathway).

2.5
Layer 6 is the pericycle.
Its functions include:

• The origin of lateral roots.
• In dicots, it contributes to the vascular cambium during secondary growth.

2.6

a) Companion cells: Phloem (Part 7)

b) Tracheids: Xylem (Part 8)

c) Xylem and phloem tissue: Vascular Cylinder/Stele (Part 9)