Long filamentous threads protruding at the end of a young cob of maize are :
1. | anthers | 2. | styles |
3. | ovaries | 4. | hairs |
In angiosperms, microsporogenesis and megasporogenesis
(1) occur in anther
(2) form gametes without further divisions
(3) involve meiosis
(4) occur in ovule
Which of of the following fruits is parthenocarpic?
1. Brinjal
2. Apple
3. Jackfruit
4. Banana
Male gametophyte in angiosperms produces
1. two sperms and a vegetative cell
2. single sperm and a vegetative cell
3. single sperm and two vegetative cells
4. three sperms
Which one of the following statements is not true?
1. Pollen grains are rich in nutrients and they are used in the form of tablets and syrups
2. Pollen grains of some plants cause severe allergies and bronchial afflictions in some
people
3. The flowers pollinated by flies and beetles secrete foul odour to attract them
4. Honey is made by bees by digesting pollen collected from flowers
Pollen grains are shed at which stage?
(1) 2 celled
(2) 3 celled
(3) Usually at 2-celled, but sometimes 3-celled
(4) Single celled stage
False fruit in an apple is formed from
(1) receptacle
(2) thalamus
(3) peduncle
(4) petals.
Seed of castor is
(1) non-endospermic, exalbuminous
(2) endospermic albuminous
(3) endospermic exalbuminous
(4) non-endospermic albuminous.
During formation of which of the following free nuclear division occurs?
(1) Flower
(2) Endosperm
(3) Gametes
(4) Fruit
Pollen grains are able to withstand extremes of temperature and dessication because their exine is composed of
(1) cutin
(2) suberin
(3) sporopollenin
(4) callose