Which one of the following statements is not true ?

Options

A. Tapetum helps in the dehiscen of anther
B. Exine of pollen grain is made up of sporopollenin
C. Pollen grains of many species cause severe allergies
D. Stored pollen in liquid nitrogen can be used in the crop breeding programmes

Answer

To determine which statement is not true, we will analyze each of the four statements provided in the question.

**Step 1: Analyze the first statement**
- The first statement claims, "Tapetum helps in the dehiscence of Anther."
- The tapetum is indeed an inner layer of the microsporangium in the anther, but its primary function is to nourish the developing pollen grains, not to assist in the dehiscence (the process of opening) of the anther. Therefore, this statement is incorrect.

**Step 2: Analyze the second statement**
- The second statement states, "Exine of pollen grain is made up of sporopollenin."
- This is true. The exine, which is the outer layer of the pollen grain, is composed of sporopollenin, a highly resistant organic material. This makes the statement correct.

**Step 3: Analyze the third statement**
- The third statement says, "Pollen grains of many species cause self-allergies."
- This statement is also true. Certain pollen grains can trigger allergic reactions in individuals, leading to respiratory issues such as asthma and bronchitis. Thus, this statement is correct.

**Step 4: Analyze the fourth statement**
- The fourth statement claims, "Stored pollen in liquid nitrogen can be used in crop breeding programs."
- This statement is accurate. Pollen can be preserved in liquid nitrogen for future use in crop breeding, similar to how seeds are stored in seed banks. Hence, this statement is also correct.

**Conclusion: Identify the incorrect statement**
- After analyzing all four statements, we find that the first statement regarding the role of tapetum in the dehiscence of anther is the only incorrect statement.

**Final Answer: The statement that is not true is: "Tapetum helps in the dehiscence of Anther."**

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