Select the false statement

Options

A. Leg-haemoglobin is present in the cytoplasm of infected nodule cells.
B. The host plant (legume) produce globin part while bacteria (Rhizobium) produces haem part of leg-haemoglobin
C. Most of our knowledge about mechanisms of absorption of nutrients by root is based on a single plant cell, isolated tissue and/or organ, and it shows that 3 main phases are involved in this process
D. lon transport across the root obeys the same biophysical laws that govern cellular transport

Answer

To solve the question of selecting the false statement regarding mineral nutrition, we will analyze each option step by step.

### Step-by-Step Solution:

**Step 1: Analyze Option 1**
- **Statement:** "Leg hemoglobin is present in the cytoplasm of the infected nodule cell."
- **Evaluation:** This statement is true. Leg hemoglobin is indeed found in the cytoplasm of infected root nodule cells in legumes, where it plays a role in oxygen regulation for nitrogen-fixing bacteria.

**Step 2: Analyze Option 2**
- **Statement:** "The host plant legume produces globin part while bacteria rhizobium produces heme part of hemoglobin."
- **Evaluation:** This statement is also true. In leghemoglobin, the globin part is synthesized by the legume, while the heme part is produced by the Rhizobium bacteria. This collaboration is essential for nitrogen fixation.

**Step 3: Analyze Option 3**
- **Statement:** "Most of our knowledge about the mechanism of absorption of nutrient by root is based on a single plant cell isolated tissue and/or organ and it shows that three main phases are involved in this process."
- **Evaluation:** This statement is false. The mechanism of nutrient absorption primarily involves two phases: the initial passive phase and the metabolic active phase, which requires ATP. Therefore, the claim of three phases is incorrect.

**Step 4: Analyze Option 4**
- **Statement:** "Iron transport across the root obeys the same biophysical laws that govern cellular transport."
- **Evaluation:** This statement is true. Iron transport in roots follows the principles of biophysical laws such as osmosis, diffusion, and active transport, which are applicable to cellular transport processes.

### Conclusion:
The false statement is **Option 3**, which incorrectly states that there are three phases involved in the absorption of nutrients by roots.

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