The only type of pollination that brings genetically different types of pollen grains to the stigma is:
Dioecy in plants prevents:
(1) Autogamy but not geitonogamy
(2) Geitonogamy but not autogamy
(3) Both autogamy and geitonogamy
(4) Neither autogamy nor geitonogamy
If the female parent produces unisexual flower:
(1) Emasculation must be done before maturity
(2) Emasculation must be done after maturity
(3) Emasculation must be done before pollination
(4) Emasculation is not needed
The central cell in the embryo sac, after triple fusion, becomes:
(1) Primary endosperm cell
The endosperm is completely consumed by the developing embryo in all of the following except:
Epicotyl has a shoot apex and a few leaf primordial enclosed in a hollow foliar structure called as the:
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