The innermost layer of the anther wall is called:
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: D
Answer: Tapetum
Explanation: The innermost wall layer is the tapetum.
Cells of sporogenous tissue undergo which division to form microspore tetrads?
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: B
Answer: Meiosis
Explanation: Cells of the sporogenous tissue undergo meiotic divisions to form microspore tetrads.
Pollen grains represent the:
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: B
Answer: Male gametophyte
Explanation: The pollen grains represent the male gametophytes.
The exine of pollen grains is made of:
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: C
Answer: Sporopollenin
Explanation: The hard outer layer called the exine is made up of sporopollenin.
Germ pores are areas on the exine where:
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: B
Answer: Sporopollenin is absent
Explanation: Pollen grain exine has prominent apertures called germ pores where sporopollenin is absent.
The vegetative cell of the pollen grain has:
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: B
Answer: Large irregularly shaped nucleus
Explanation: The vegetative cell... has abundant food reserve and a large irregularly shaped nucleus.
In 60% of angiosperms, pollen is shed at:
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: B
Answer: 2-celled stage
Explanation: In over 60 per cent of angiosperms, pollen grains are shed at this 2-celled stage.
Parthenium or carrot grass causes:
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: B
Answer: Pollen allergy
Explanation: Parthenium or carrot grass... causes pollen allergy.
Pollen grains can be stored in liquid nitrogen at:
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: B
Answer: -196 C
Explanation: It is possible to store pollen grains... in liquid nitrogen (-196 C).
A multicarpellary, syncarpous pistil is found in:
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: B
Answer: Papaver
Explanation: Pistils may be fused together (syncarpous) (Figure 1.7b - Papaver).