Sporopollenin is a constituent of pollen exine.
It can be degraded by the action of
(1) enzymes
(2) high temperature
(3) strong acids
(4) cannot be degraded
The pollen grains of rice and wheat lose their viability in ___ minutes of their release.
(1) 30
(2) 10
(3) 60
(4) 90
After double fertilizaton, a mature ovule has
(1) 1 diploid and 1 haploid cell
(2) 1 diploid and 1 triploid cell
(3) 2 haploid and 1 triploid cell
(4) 1 haploid and 1 triploid cell
How many haploid nuclei are present in a mature pollen grain?
(1) One
(2) Two
(3) Three
(4) Four
What is the correct sequence of the formation of female gametophyte in angiosperms?
(1) Nucellus, megapore tetrad, megaspore mother cell, megaspore, female gametophyte
(2) Megaspore tetrad, nucellus, megaspore mother cell, megaspore, female gametophyte
(3) Nucellus, megaspore mother cell, megaspore tetrad, megaspore, female gametophyte
(4) Megaspore mother cell, megaspore tetrad, megaspore, nucellus, female gametophyte
Primary endosperm nucleus (PEN) is formed by the fusion of
1. 2 polar nuclei + 1 synergid cell nucleus
2. 1 polar nucleus + 1 antipodal cell nucleus + 1 synergid cell nucleus
3. 2 polar nuclei + 1 male gamete nucleus
4. 2 antipodal cell nuclei + 1 male gamete nucleus
Match column I with column II and select the correct option from the given codes.
Column - I | Column - II | ||
A. | Parthenocarpy | (i) | Seed formation without fertilization |
B. | Polyembryony | (ii) | More than one embryo in same seed |
C. | Apomixis | (iii) | Seedless fruits without fertilization |
D. | Somatic embryogenesis | (iv) | Embryo develops from a somatic cell |
1. A - (iv), B - (ii), C - (iii), D - (i)
2. A - (iii), B - (ii), C - (i), D - (iv)
3. A - (i), B - (iv), C - (iii), D - (ii)
4. A - (ii), B - (iii), C - (i), D - (iv)
The following is the diagram of T.S. of anther. Identify the parts labelled A, B and C.
1. | A - Connective tissue, B - Pollen grains, C - Endothecium |
2. | A - Endothecium, B -Connective tissue, C - Pollen grains |
3. | A - Pollen grains, B - Connective tissue, C - Endothecium |
4. | A - Endothecium, B - Pollen grains, C - Connective tissue |
Select the option that contains all plants which produce non-endospermic seeds.
(1) Gram, Pea, Bean, Groundnut
(2) Castor, Peanut, Orchid, Wheat
(3) Coconut, Walnut, Wheat, Gram
(4) Castor, Maize, Coconu, Orchid
Pollination in Rafflesia is occurred by
a. carrion flies
b. elephant
c. bat
d. crow