Which one of the following statements is not true ?

Options

A. stored pollen in liquid nitrogen can be used in the crop breeding programmes
B. tapeturn helps in the dehiscence of anther
C. exine of pollen grains is made up of sporopolleniin
D. pollen grans of many species cause severse allergies

Answer

To determine which statement is not true, let's analyze each statement one by one:

1. **Statement 1**: "The stored pollen in the liquid nitrogen can be used in the crop breeding programs."
- This statement is true. The process of cryopreservation involves storing pollen at very low temperatures (like in liquid nitrogen at -196 degrees Celsius) to preserve it for future use in crop breeding programs.

2. **Statement 2**: "The tapetum helps in the desense of the anther."
- This statement is not true. The tapetum is the innermost layer of the anther and plays a crucial role in providing nourishment to the developing pollen grains. It does not help in the "desense" (which seems to be a typographical error for "defense" or "destruction") of the anther.

3. **Statement 3**: "The exine of the pollen grain is made up of sporopollenin."
- This statement is true. The exine is the outermost layer of the pollen grain, and it is indeed composed of sporopollenin, which is known for its decay resistance and durability.

4. **Statement 4**: "The pollen grains of many species cause several allergies."
- This statement is also true. Pollen grains can trigger allergic reactions in some individuals, particularly during certain seasons when pollen is abundant.

Based on this analysis, the statement that is not true is **Statement 2**: "The tapetum helps in the desense of the anther."