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Thickness of exine is increased by :...

Thickness of exine is increased by :

A

Pollen kitt

B

Cellulose

C

Pectocellulose

D

Ubisch bodies

Text Solution

AI Generated Solution

The correct Answer is:
To determine what increases the thickness of the exine in pollen grains, we can follow these steps: ### Step-by-Step Solution: 1. **Understand the Structure of Pollen Grains**: - Pollen grains are the male gametes in flowering plants and have a protective outer covering known as the sporoderm. 2. **Identify the Layers of the Sporoderm**: - The sporoderm consists of two layers: the outer layer called the exine and the inner layer called the intine. 3. **Composition of the Exine**: - The exine is primarily composed of a substance known as sporopollenin, which is one of the most resistant organic materials. 4. **Factors Affecting Exine Thickness**: - The thickness of the exine can be influenced by various factors, including the presence of certain bodies that contribute to its development. 5. **Role of Ubisch Bodies**: - Ubisch bodies are small structures found in the tapetum layer of the anther. They play a crucial role in the development of pollen grains and are involved in the formation of the exine. 6. **Conclusion**: - The thickness of the exine is increased by the presence of Ubisch bodies, which contribute to the deposition of sporopollenin in the exine layer. ### Final Answer: The thickness of the exine is increased by Ubisch bodies. ---
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