In some members of which of the following pairs of families, pollen grains retain their viability for months after release?
1. Poaceae; Solanaceae
2. Rosaceae; Leguminosae
3. Poaceae; Rosaceae
4. Poaceae; Leguminosae
Which of the following has proved helpful in preserving pollens as fossils?
1. | Pollen kit | 2. | Cellulosic intine |
3. | Oil content | 4. | Sporopollenin |
Pollen grains can be stored for several years in liquid nitrogen having a temperature of:
1. | –120 °C | 2. | –80 °C |
3. | –196 °C | 4. | –160 °C |
In angiosperms, microsporogenesis and megasporogenesis?
1. Occur in anther
2. Form gametes without further divisions
3. Involve meiosis
4. Occur in ovule
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 |
Which one of the following statements is wrong?
1. | Vegetative cell is larger than generative cell |
2. | Pollen grains in some plants remain viable for months |
3. | Intine is made up of cellulose and pectin |
4. | When pollen is shed at a two-celled stage, double fertilization does not take place |