Q. No.A particular species of the plant produces light, non-sticky pollen in large numbers and its stigmas are long and feathery. These
modifications facilitate pollination by:
1.
Insects
2.
Water
3.
Wind
4.
Animals
modifications facilitate pollination by:
In an embryo sac, the cells that degenerate after fertilisation are:
1. Synergids and primary endosperm cell
2. Synergids and antipodals
3. Antipodals and primary endosperm cell
4. Egg and antipodals
In the embryos of a typical dicot and a grass, true homologous structures are:
| 1. | Coleorhiza and coleoptile | 2. | Coleoptile and scutellum |
| 3. | Cotyledons and scutellum | 4. | Hypocotyl and radical |
The phenomenon observed in some plants wherein parts of the sexual apparatus are used for forming embryos without fertilisation is called
| 1. | Parthenocarpy | 2. | Apomixis |
| 3. | Vegetative propagation | 4. | Sexual reproduction |
In a type of apomixis known as adventive embryony, embryos develop directly from:
1. Nucellus or integument
2. Zygote
3. Synergids of antipodals of embryo sac
4. Accessory embryo sac in the ovule
Parthenocarpic fruits are produced by:
| 1. | Treating plants with phenyl Mercuric acetate. |
| 2. | Treating plants with low concentrations of gibberellic acid and auxin. |
| 3. | Removing androecium of flowers before releasing pollen grains. |
| 4. | Raising plants from vernalised seeds. |
An organic substance that can withstand environmental extremes and cannot be degraded by any enzyme is:
| 1. | Cuticle | 2. | Sporopollenin |
| 3. | Lignin | 4. | Cellulose |
Perisperm differs from endosperm in:
| 1. | having no reserved food. |
| 2. | being a diploid tissue. |
| 3. | its formation by fusion of a secondary nucleus with several sperms. |
| 4. | being a haploid tissue. |
Which one of the following statements is not true?
| 1. | Pollen grains of some plants cause severe allergies and bronchial afflictions in some people. |
| 2. | The flowers pollinated by flies and bats secrete foul odour to attract them. |
| 3. | Honey is made by bees by digesting pollen collected from flowers. |
| 4. | Pollen grains are rich in nutrients, and they are used in the form of tablets and syrups. |
Flowers that have a single ovule in the ovary and are packed into inflorescence are usually pollinated by:
| 1. | Water | 2. | Bee |
| 3. | Wind | 4. | Bat |
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