Which one of the following is surrounded by a callose wall?
(1) Microspore mother cell
(2) Male gemete
(4) Pollen grain
What would be the number of chromosomes in the cells of the aleurone layer in a plant species with 8 chromosomes in it synergids ?
Parthenocarpic tomato fruits can be produced by :
(1) removing androecium of flowers before pollen grains are released
(2) treating the plants with low concentrations of gibberellic acid and auxins
(3) raising the plants from vernalized seeds
(4) treating the plants with phenylmercuric acetate.
Long filamentous threads protruding at the end of a young cob of maize are :
The arrangement of the nuclei in a normal embryo sac in the dicot plant is :
In angiosperms, microsporogenesis and megasporogenesis
(1) occur in anther
(2) form gametes without further divisions
(3) involve meiosis
(4) occur in ovule
Coconut water from a tender coconut is
1. Immature embryo
2. Free nuclear endosperm
3. Innermost layers of the seed coat
4. degenerated nucellus
Which of of the following fruits is parthenocarpic?
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
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