Sexual Reproduction in Flowering Plants MCQs for NEET — Botany Questions with Answers

The above mentioned points explains autogamy.

Allogamy: It is the deposition of pollen grains from the anther of one flower to the stigma of another flower, either in same plant or different plant of the same species.

Xenogamy: Transfer of pollen grains from anther to the stigma of a different plant. This is the only type of pollination which during pollination brings genetically different types of pollen grains to the stigma.

Cross pollination: The transfer of pollen grains from anther of one plant to the stigma of another plant.

(page- 27, 28)

Bees are the dominant biotic pollinating agents because of the secretion of

nectar by flowers, which is collected by them as floral reward to make

honey.

Some flowers are specially adapted for particular species of animals like

daisy and aster attracts bees.

Nectar, pollen grains and shelter for egg laying (the moth deposits its

eggs in the locule of the ovary and the flower, in turn, gets pollinated by

the moth) are the usual floral rewards.

(page- 30)

Outcrossing refers to a cross between individuals of same breed of a

species that have no common ancestors upto 4-6 generations. This

increases genetic diversity by broadening the genetic pool. 

This also limits the chances of bad traits (recessive ones) from getting

passed on. Thus offsprings from outcrosses show additional health and

vigor.

If the female parent bears bisexual flowers, removal of anthers from the flower bud before the anther dehisces is done using a pair of

forceps-emasculation.

Emasculated flowers have to be covered with a bag of suitable size,

generally made up of butter paper, to prevent contamination of its stigma

with unwanted pollen. This process is called bagging.

When the stigma of bagged flower attains receptivity, mature pollen grains

collected from anthers of the male parent (cross pollination) are dusted on

the stigma, and the flowers are rebagged.

(page-33)

It is the outermost layer of endosperm of wheat and other grains. It is a

single layer of cells that synthesizes enzyme alpha-amylase during

germination into endosperm which breaks down starch into maltose and

glucose.

If favourable conditions like- adequate moisture, oxygen and suitable

Temperature, a seed germinates. But it may enter a state of inactivity

called dormancy when not provided with favourable conditions.

(page-36)

The general metabolic activity of embryo slows down when it enters into

state of dormancy when not provided with favourable conditions like

oxygen, moisture and suitable temperature.

(page-36)

Pomegranate would lose its economic value when produced  by

parthenocarpy because parthenocarpy makes fruit seedless and thus

useless.

Orchid fruits contain thousands of tiny seeds. Similar is the case in fruits of

some parasitic species such as Orobanche and Striga.

(page-38)

Hybrid seeds have to be produced year after year because if the seed collected from hybrid plant are sown, the plant in the progeny will segregate (Mendel’s law of segregation) and thus do not maintain hybrid characters.

But if these hybrids are made into apomicts, there is no

segregation of characters in the hybrid progeny. Then the farmers can

keep on using the hybrid seeds to raise new crop year after year and there

is no need to buy hybrid seeds every year.

(page-39)