Sexual Reproduction in Flowering Plants

NEET Biology · 120 questions · Page 8 of 12 · Click an option or "Show Solution" to reveal answer

Q71

Which one of the following statements is not true?

A Tapetum helps in the dehiscence of anther

B Exine of pollen grains is made up of sporopollenin

C Pollen grains of many species cause severe allergies

D Stored pollen in liquid nitrogen can be used in the crop breeding programmes

Correct Answer

Option A

Solution

(a) Tapetum nourishes pollen; it is the endothecium that helps in anther dehiscence.

Q72

The body of the ovule is fused within the funicle at

A Micropyle

B Nucellus

C Chalaza

D Hilum

Correct Answer

Option D

Solution

(d) Hilum: attachment point of funicle and ovule body.

Q73

Micropyle of seed is involved in the passage of the

A male gamete

B pollen tube

C water

D gases

Correct Answer

Option B

Solution

(b) The micropyle serves as entry point for the pollen tube during fertilization.

Q74

Double fertilization and triple fusion were discovered by

A Hofmeister

B Nawaschin and Guignard

C Leeuwenhoek

D Strasburger

Correct Answer

Option B

Solution

(b) Nawaschin and Guignard first demonstrated double fertilization in Fritillaria and Lilium.

Q75

Double fertilization is characteristic of

A Angiosperms

B Pteridophytes

C Gymnosperms

D Bryophytes

Correct Answer

Option A

Solution

(a) Double fertilization is unique to angiosperms.

Q76

In angiosperms, triple fusion is required for the formation of

A embryo

B endosperm

C seed coat

D fruit wall

Correct Answer

Option B

Solution

(b) Triple fusion produces the primary endosperm nucleus (3n).

Q77

If an angiospermic male plant is diploid and female plant tetraploid, the ploidy level of endosperm will be

A haploid

B triploid

C tetraploid

D pentaploid

Correct Answer

Option D

Solution

(d) Tetraploid female polar nuclei = 2n each; diploid male gamete = n; endosperm = 2n+2n+n = 5n = pentaploid.

Q78

Double fertilisation leading to initiation of endosperm in Angiosperms require

A fusion of one polar nucleus and the second male gamete only

B fusion of two polar nuclei and the second male gamete

C fusion of four or more polar nuclei and the second male gamete only

D all the above kinds of fusion in different angiosperms

Correct Answer

Option B

Solution

(b) Second male gamete fuses with two polar nuclei forming triploid primary endosperm nucleus.

Q79

A diploid female plant and a tetraploid male plant are crossed. The ploidy of endosperm shall be

A tetraploid

B triploid

C diploid

D pentaploid

Correct Answer

Option A

Solution

(a) Diploid female: 2 polar nuclei each n; tetraploid male: gamete 2n; endosperm = n+n+2n = 4n (tetraploid).

Wait — diploid female has polar nuclei each n=1n; male tetraploid gamete = 2n; endosperm = 1+1+2 = 4n?

Actually diploid=2n so polar nuclei=n; tetraploid=4n so gamete=2n; endosperm=n+n+2n=4n = tetraploid.

Q80

Double fertilization is

A Fusion of two male gametes of a pollen tube with two different eggs

B Fusion of one male gamete with two polar nuclei

C Syngamy and triple fusion

D Fusion of two male gametes with one egg

Correct Answer

Option C

Solution

Ready for a full NEET mock test? Timed · full syllabus · instant results

Take a Mock Test →