Pollen grains remain preserved as fossils due to the presence of :
- Epidermal layer
- Tapetum
- Exine layer
- Intine layer
Answer
(3) Exine layer
Solution
The exine of the pollen grain is made of sporopollenin, one of the most resistant organic materials known. It withstands high temperatures, strong acids and alkalis, and no enzyme can degrade it.
Hence pollen grains are well preserved as fossils.
Answer: (3)