Sexual Reproduction in Flowering Plants

Which one of the following statements is correct?

1. Cleistogamous flowers are always autogamous.
2. Xenogamy occurs only by wind pollination.
3. Chasmogamous flowers do not open at all.
4. Geitonogamy involves the pollen and stigma of flowers of different plants.

Which of the following statements is correct?

1. Sporopollenin can be degraded by enzymes.
2. Sporopollenin is made up of inorganic materials.
3. Sporopollenin can withstand high temperatures as well as strong acids and alkalis.
4. Sporopollenin can withstand high temperatures but not strong acids.

The viability of seeds is tested by :

1. 2,3,5-triphenyl tetrazolium chloride
2. Safranine
3. 2,6-dichlorophenol indophenol
4. DMSO

What is the function of germ pore?

1. Emergence of radicle
2. Absorption of water for seed germination
3. Initiation of pollen tube
4. Release of male gametes

Which one of the following statements is wrong?

1. When pollen is shed at two-celled stage, double fertilization does not take place.
2. Vegetative cell is larger than generative cell.
3. Pollen grains in some plants remain viable for months.
4. Intine is made up of cellulose and pectin.

Plants with ovaries having only one or a few ovules, are generally pollinated by

1. bees
2. butterflies
3. birds
4. wind

Both, autogamy and geitonogamy are prevented in

1. Papaya
2. cucumber
3. castor
4. maize.

An organic substance that can withstand environmental extremes and cannot be degraded by any enzyme is

1. cuticle
2. sporopollenin
3. lignin
4. cellulose.

Even in absence of pollinating agents seed-setting is assured in

1. Commelina
2. Zostera
3. Salvia
4. fig.

In angiosperms, functional megaspore develops into

1. embryo sac
2. ovule
3. endosperm
4. pollen sac.