The probability of fruit set in a self-pollinated bisexual flower of a plant is far greater than a dioecious plant explain

2

(a)

In a self-pollinated bisexual flower, the anthers and sigma lie close to each other and when the anthers dehisce, the pollen grains fall on the stigma and pollination is effected even in the absence of a pollinator.
But in dioecious plants, an agent or a pollinator is necessary.

Name the type of pollination in self-incompatible plants.

2

(a)

Cross pollination or xenogamy.

Are pollination and fertilisation necessary in apomixis? Give reason.

2

(a)

What is seed dormancy ? Give any two advantages of seed dormancy.

2

(a)

Indicate the stages where meiosis and mitosis occur (1, 2 or 3) in the flow chart
Megspore mother cell \(\overset { 1 }{ \rightarrow } \) Megaspores \(\overset { 2 }{ \rightarrow } \) Embryo sac \(\overset { 3 }{ \rightarrow } \)Egg.

2

(a)

Which are three cells found in pollen grain when it is shed at the three called stage?

2

(a)

Which is the triploid tissue in a fertilized ovule? How is the triploid condition achieved ?

2

(a)

Name the parts of pistil which develop into fruits and seeds

2

(a)

Name the organic materials of which exine and intine of angiosperm pollen grains are made up of. Explain the role of exine.

2

(a)

Some plants have a mechanism of shedding of pollen before maturation of stigma. Why?

2

(a)