Based on Figure 2, identify parts M, N, and O, state which part would be stained blue and why, and name the processes by which nitrate ions and water enter the root through structures labelled L. Also

Here are the answers to the questions based on Figure 2:

a)

• (i) Identify the parts labelled M, N and O in Figure 2. M: $\boxed{\text{Epidermis / Root hair cell}}$ N: $\boxed{\text{Cortex}}$ O: $\boxed{\text{Xylem}}$

• (ii) Which labelled part in Figure 2 would be stained blue? $\boxed{\text{O}}$

• (iii) Give a reason for your answer in (a)(ii). Part O (xylem) is responsible for the transport of water and dissolved substances from the root to other parts of the plant. The blue solution, being water-based, would be transported through the xylem.

b) Name the process by which

• (i) nitrate ions would enter the root through structures labelled L. $\boxed{\text{Active transport}}$
• (ii) water enters the root through structures labelled L. $\boxed{\text{Osmosis}}$

c) State two ways in which the structure of the part labelled L is adapted to its function.

1. $\boxed{\text{It has a long and narrow extension (root hair) to increase the surface area for absorption.}}$
2. $\boxed{\text{It has a thin cell wall and cell membrane to allow for faster diffusion and osmosis.}}$ (Other valid answers include: high concentration of solutes in cytoplasm to maintain a steep water potential gradient; numerous mitochondria to provide energy for active transport.)