The micropyle remains as a small pore in the seed coat. During germination, this facilitates entry of:
(1) Only I
(2) Only II
(3) Both I and II
(4) Neither I nor II
Why do seeds need water to germinate?
(1) Following hydration, enzymes break down stored food and make it available for the embryo.
(2) Water provides energy.
(3) Water activates the chlorophyll molecules so that photosynthesis can begin.
(4) Water dissolves the minerals in the soil so that they become available to the seed.
Genetic self-incompatibility tends to increase
(1) pollen dispersal
If a flower is to be pollinated by moths, it should
(1) be heavily scented
(2) be shaped like a tulip
(3) close about noon
(4) be brightly colored
A fertilized embryo sac of an angiosperm contains:
I. Haploid cells
II. Diploid cells
III. Triploid cells
1. I and II only
2. I and II only
3. II and III only
4. I, II and III
The intine of the pollen grain is a:
1. Thick and discontinuous layer made of sporopollenin
2. Thick and continuous layer made of sporopollenin
3. Thin and discontinuous layer made of cellulose and pectin
4. Thin and continuous layer made of cellulose and pectin
In the monosporic embryo sac of a flowering plant, the number of nuclei that get surrounded by cell walls and thus are organized into cells is:
Female flowers remain submerged in water and the pollen grains are released inside the water in:
1. Sea grasses
3. Water lily
4. Water hyacinth
Scientists are trying to transfer apomictic genes into hybrid varieties of several of our food and vegetable crops so that:
1. They get resistance against common pathogens
2. The yield of these plants can be increased many folds
3. Hybrid seeds need not be produced every year
4. Their germplasm is easily stored in labs for further research
Which of the following is the most common abiotic pollinating agent?
2. Birds and bats