Read the following statements carefully and select the correct
a. Tapetum cells possess dense cytoplasm and generally have more than one nucleus
b. Sporopollenin is absent in the areas called germ pore
c. Generative cell is small, spindle shaped with a irregularly shaped nuclei
d. Spindle of first mitosis in pollen is asymmetric
1. a,b,c & d
2. a,b & c
3. a,c & d
4. a,b & d
When both male and female flowers are present on the same plant, then plant is said to be:
1. Bisexual
2. Monoecious
3. Unisexual
4. Dioecious
Seeds offer several advantages to angiosperms. Seed formation is more dependable because:
1. Seeds have better adaptive strategies for dispersal
2. Reproductive processes become independent of water
3. Hard seed coat provides protection to the young embryos
4. They generate new genetic combinations leading to variations
Ovule generally differentiate a single _____ in the ______ region of the nucellus.
(1) Megaspore mother cell, micropylar
(2) Megaspore, micropylar
(3) Megaspore, mother cell, chalazal
(4) Primary
In which one of the following, both autogamy and geitonogamy are prevented?
1. Wheat
2. Papaya
3. Castor
4. Maize
What type of pollination takes place in Vallisneria?
1. | Pollination occurs in submerged conditions by water. |
2. | Flowers emerge above the surface of water and pollination occurs by insects. |
3. | Flowers emerge above the water surface and pollen is carried by the wind. |
4. | Male flowers are carried by water currents to female flowers at the surface of the water. |
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
A: | Pollen grains carry the male gamete from microsporangium to micropyle of ovule in angiosperms. |
B: | Pollen grain itself a male gamete further divides and form another one on stigma only. |
1. Both A and B are correct
2. A is correct only
3. B is correct only
4. Both A and B are incorrect
Most abundant/common type of pollen tetrad is _________ and it is formed due to _________ cytokinesis.
1. Tetrahedral, successive
2. Tetrahedral, simultaneous
3. Isobilateral, successive
4. Isobilateral, simultaneous
Double fertilization is different from single fertilization because of the presence of
1. Syngamy
2. Seed
3. Triple fusion
4. Megaspore and micropore