Which of the following statement is not true ?

Options

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

Answer

To determine which statement is not true, we will analyze each statement one by one:

1. **Statement A:** "The enzyme of pollen grains is made up of sporopollenin."
- **Analysis:** This statement is true. Sporopollenin is indeed the outer covering of pollen grains and is known for its durability and resistance to degradation.

2. **Statement B:** "The pollen grains of many species cause several allergies."
- **Analysis:** This statement is also true. Pollen grains are a common cause of seasonal allergies, often referred to as hay fever, affecting many individuals when they are exposed to pollen in the air.

3. **Statement C:** "Stored pollen in liquid nitrogen can be used in crop breeding programs."
- **Analysis:** This statement is true as well. Pollen can be preserved in liquid nitrogen at very low temperatures, which allows it to be stored for extended periods and used in crop breeding techniques.

4. **Statement D:** "Tapetum helps in the dehiscence of anther."
- **Analysis:** This statement is not true. The dehiscence of the anther, which is the process by which pollen is released, is primarily facilitated by the anther wall (specifically the layer called the androthecium), not the tapetum. The tapetum serves to nourish the developing pollen grains.

**Conclusion:** The statement that is not true is **Statement D**.