Sexual Reproduction in Flowering Plants — Page 2 | NEET Biology

Q11

An organic substance that can withstand environmental extremes and cannot be degraded by any enzyme is

A Cuticle

B Sporopollenin

C Lignin

D Cellulose

Correct Answer

Option B

Solution

(b) Sporopollenin is the most resistant biological substance known.

Q12

Both, autogamy and geitonogamy are prevented in

A Papaya

B Cucumber

C Castor

D Maize

Correct Answer

Option A

Solution

(a) Papaya is dioecious, preventing both autogamy and geitonogamy.

Q13

Which of the following statements is correct about sporopollenin?

A Sporopollenin can withstand high temperatures but not strong acids

B Sporopollenin can be degraded by enzymes

C Sporopollenin is made up of inorganic materials

D Sporopollenin can withstand high temperatures as well as strong acids and alkalis

Correct Answer

Option D

Solution

(d) Sporopollenin is extremely resistant — withstands high temperature, strong acids and alkalis.

Q14

Animal vectors are required for pollination in

A Maize

B Vallisneria

C Mulberry

D Cucumber

Correct Answer

Option D

Solution

(d) Cucumber is pollinated by bees (entomophily).

Q15

Megaspores are produced from the megaspore mother cells after

A Meiotic division

B Mitotic division

C Formation of a thick wall

D Differentiation

Correct Answer

Option A

Solution

(a) MMC undergoes meiosis to form 4 haploid megaspores (megasporogenesis).

Q16

Which one of the following statements is correct about pollination types?

A Geitonogamy involves the pollen and stigma of flowers of different plants

B Cleistogamous flowers are always autogamous

C Xenogamy occurs only by wind pollination

D Chasmogamous flowers do not open at all

Correct Answer

Option B

Solution

(b) Cleistogamous flowers never open, ensuring autogamy.

Q17

Which one of the following statements is correct about pollen?

A Sporogenous tissue is haploid

B Endothecium produces the microspores

C Tapetum nourishes the developing pollen

D Hard outer layer of pollen is called intine

Correct Answer

Option C

Solution

(c) Tapetum nourishes developing pollen grains.

Q18

Product of sexual reproduction generally generates

A Prolonged dormancy

B New genetic combination leading to variation

C Large biomass

D Longer viability of seeds

Correct Answer

Option B

Solution

(b) Sexual reproduction leads to genetic variation in offspring.

Q19

Advantage of cleistogamy is

A More vigorous offspring

B No dependence of pollinators

C Vivipary

D Higher genetic variability

Correct Answer

Option B

Solution

(b) Cleistogamy ensures pollination without pollinators.

Q20

Megasporangium is equivalent to

A Fruit

B Nucellus

C Ovule

D Embryo sac

Correct Answer

Option C

Solution

(c) Ovule = integumented megasporangium.