Which one is surrounded by callose wall
1. Male gamete
2. Pollen grain
3. Egg
4. Microspore mother cell
Unisexuality of flowers prevents
1. Getionogamy but not xenogamy
2. Autogamy and geitonogamy
3. Autogamy but not geitonogamy
4. Both getionogamy and xenogamy
Flowers are unisexual in:
1. Cucumber
2. China rose
3. Onion
4. Pea
Megasporangium is equivalent to :
1. Fruit
2. Nucellus
3. Ovule
4. Embryo sac
Dioecy in flowering plants prevents:
1. autogamy but not geitonogamy
2. geitonogamy but not autogamy
3. both autogamy and geitonogamy
4. neither autogamy nor geitonogamy
What is the function of germ pores?
1. Absorption of water for seed germination
2. Initiation of pollen tube
3. Release of male gametes
4. The emergence of radicle
(a) | the female flower buds of plant producing unisexual flower need not be bagged. |
(b) | there is no need to emasculate unisexual flowers of selected female parent |
(c) | emasculated flowers are to be bagged immediately after cross pollination |
(d) | emasculated flowers are to be bagged after removal of anthers |
(e) | bisexual flowers, showing protogyny are never selected for cross |
1. | (a), (b) and (c) only | 2. | (b), (c) and (d) only |
3. | (b), (c) and (e) only | 4. | (a), (d) and (e) only |
Which is the most common type of embryo sac in angiosperms?
1. Tetrasporic with one mitotic stage of division
2. Monosporic with three sequential mitotic divisions
3. Monosporic with two sequential mitotic divisions
4. Bisporic with two sequential mitotic divisions
Apomictic embryos in citrus arise from
1. Maternal sporophytic tissue in ovule
2. Antipodal cells
3. Diploid egg
4. Synergids
Plants with ovaries having only one or a few ovules, are generally pollinated by:
1. Bees
2. Butterflies
3. Birds
4. Wind