The pollen grains are shed at two-celled stage in
(1) 80% angiosperms
(2) 40% angiosperms
(3) 30% angiosperms
(4) 60% angiosperms
Match the following:
1 | Male gametophyte | I | Embryo sac |
2 | Female gametophyte | II | Ovule |
3 | Megasporangium | III | Pollen grains |
4 | Microsporangium | IV | Pollen sacs |
(1) 1-III ; 2-I ; 3-II ; 4-IV
(2) 1-I ; 2-II ; 3-III ; 4-IV
(3) 1-IV ; 2-III ; 3-II ; 4-I
(4) 1-III ; 2-II ; 3-I ; 4-IV
The following figure represents :
(1) Transverse section of young anther
(2) 3-D cut section of mature anther
(3) Cut section of filament
(4) Transverse section of mature filament
Identify A, B and X :-
X contains two cells - A and B. B is bigger than A, it has abundant food reserve and large irregularly shaped nucleus. A is small and floats in the cytoplasm of B. It is spindle shaped with dense cytoplasm and nucleus.
A | B | X | |
(1) | Vegetative cell | Generative cell | Pollen grain |
(2) | Generative cell | Vegetative cell | Pollen grain |
(3) | Generative cell | Vegetative cell | Anther |
(4) | Generative cell | Vegetative cell | Filament |
Which among the following is not true about pollen grain?
(1) Rich in nutrients.
(2) Many species cause severe allergies and bronchial afflictions in some people often leading to chronic respiratory disorders– asthma, bronchitis, etc.
(3) Pollen consumption has been claimed to increase the performance race horses.
(4) Parthenium is used against pollen allergy.
Which among the following is not a feature of pistil?
(1) Monocarpellary
(2) Syncarpous
(3) Monosporic
(4) Apocarpous
A, B, C, D in the following diagram respectively are:-
(1) Hilum, funicle, inner integument, micropyle
(2) Hilum, funicle, outer integument, micropyle
(3) Funicle, outer integument, nucellus, chalazal pole
(4) Funicle, outer integument, nucellus, micropylar end
Microsporangium is generally surrounded by 4 wall layers. Which of the following 3 wall layers perform the function of protection and help in the dehiscence of anther to release the pollen?
(1) Epidermis, tapetum, endothecium
(2) Epidermis, aril, endothecium
(3) Epidermis, endodermis, mesocarp
(4) Epidermis, middle layer and endothecium
The above diagram shows some stages in microgametogenesis. Identify A, Band C:
A B C
(1) Symmetric spindle Generative cell Vegetative cell
(2) Symmetric spindle Vegetative cell Generative cell
(3) Asymmetric spindle Vegetative cell Generative cell
(4) Asymmetric spindle Generative cell Vegetative cell
The viability of pollen grains depends upon:
(1) Prevailing temperature
(2) Prevailing humidity
(3) Genetic potentiality of the concerned species
(4) All of the above