What do you understand by pollen grains?
Important Questions on Reproduction in Lower and Higher Plants
Assertion Xenogamy involves transfer of pollen grains from the flower of one plant to the stigma of another plant.
Reason This is the only type of pollination which brings genetically different types of pollen grains to the stigma.
The correct answer is:
Among the following statements related to pollens, choose the correct one.
Statement : In of angiosperms pollen grains are shed at the —celled stage.
Statement : Intine is made of cellulose and pectin, and it is discontinuous with germ pores.
Assertion Pollengrains are well preserved as fossils
Reason The exine of pollen grains is made up of sporopollenin, which can withstand high temperatures, strong acids and alkali.
(A) Disassociation of microspore as pollen grains
(B) Anther maturation and dehydration
(C) Pollen mother cell undergoes meiotic division
(D) Microspore tetrad
A- Endothecium
B- Tapetum
C- Epidermis
D- Middle Layer
Assertion (A): In some plants the generative cell divides and forms the two male gametes during pollen tube growth in stigma.
Reason(R): In plants which shed pollen in three cell stage, the pollen tube will have two male gametes from the beginning.
The correct option among the following is:
Mateh the following?
| Column - I | Column - II | Column - III | |||
| (a) | Epidermis | (i) | Multi nucleated | (p) | Protection |
| (b) | Endothecium | (ii) | Homogenous | (q) | Formation of Micropores |
| (c) | Tapetum | (iii) | One celled thick | (r) | dehiscence of anther |
| (d) | Sporogenous tissue | (iv) | Fibrous thickness | (s) | Nourishment |
A) Several hormonal and structural changes are initiated for the development of floral primordium.
B) Each anther will have two sporangia at the sides.
C) Stomium will be useful for the dehiscence of pollen sacs.
D) Pollen grains can be stored at .
E) Pollen viability in rice will be days.
