NCERT Solutions for Class 12 Biology
Chapter 1 – Sexual Reproduction In Flowering Plants
1. Name the parts of an angiosperm flower in which the development of male and female
gametophytes takes place.
Ans: In pollen sacs of the anther, male gametophytes (microgametogenesis) develop up to the
2-celled stage. The nucellus of an ovule is where the gametophyte develops
(megagametogenesis).
2. Differentiate between microsporogenesis and megasporogenesis. Which type of cell
division occurs during these events? Name the structures formed at the end of these two
events?
Ans: Microsporogenesis and Megasporogenesis differ in the following ways:
Microsporogenesis Megasporogenesis
The process by which microspore Megasporogenesis is the process by which
mother cells divide and produce pollen megaspore mother cells are formed and
grains is known as microsporogenesis. differentiate into megaspores by meiosis.
Class XII Biology www.vedantu.com 1
, Located within the pollen sac of the It is present in the nucellus of the ovule.
anthers.
A pollen grain produced by a The megaspores have only one functional
microspore mother cell functions megaspore.
properly.
Results in the formation of pollen Resulting in the formation of embryo sacs
grains (male gametophyte) (female gametophyte)
Microspore mother cells and The mother cells for megaspores and microspores
megaspore mother cells are every enlarge and undergo meiosis in order to produce
diploid, as they have two sets of four haplotypic cells called megaspores and
chromosomes. microspores, respectively.
3. Arrange the following terms in the correct developmental sequence: Pollen grain,
sporogenous tissue, microspore tetrad, pollen mother cell, male gametes.
Ans: The sporogenous tissue is composed of a pollen mother cell, a microspore tetrad, pollen
grains, and male gametes.
4. With a neat, labeled diagram, describe the parts of a typical angiosperm ovule.
Ans:
Class XII Biology www.vedantu.com 2
Chapter 1 – Sexual Reproduction In Flowering Plants
1. Name the parts of an angiosperm flower in which the development of male and female
gametophytes takes place.
Ans: In pollen sacs of the anther, male gametophytes (microgametogenesis) develop up to the
2-celled stage. The nucellus of an ovule is where the gametophyte develops
(megagametogenesis).
2. Differentiate between microsporogenesis and megasporogenesis. Which type of cell
division occurs during these events? Name the structures formed at the end of these two
events?
Ans: Microsporogenesis and Megasporogenesis differ in the following ways:
Microsporogenesis Megasporogenesis
The process by which microspore Megasporogenesis is the process by which
mother cells divide and produce pollen megaspore mother cells are formed and
grains is known as microsporogenesis. differentiate into megaspores by meiosis.
Class XII Biology www.vedantu.com 1
, Located within the pollen sac of the It is present in the nucellus of the ovule.
anthers.
A pollen grain produced by a The megaspores have only one functional
microspore mother cell functions megaspore.
properly.
Results in the formation of pollen Resulting in the formation of embryo sacs
grains (male gametophyte) (female gametophyte)
Microspore mother cells and The mother cells for megaspores and microspores
megaspore mother cells are every enlarge and undergo meiosis in order to produce
diploid, as they have two sets of four haplotypic cells called megaspores and
chromosomes. microspores, respectively.
3. Arrange the following terms in the correct developmental sequence: Pollen grain,
sporogenous tissue, microspore tetrad, pollen mother cell, male gametes.
Ans: The sporogenous tissue is composed of a pollen mother cell, a microspore tetrad, pollen
grains, and male gametes.
4. With a neat, labeled diagram, describe the parts of a typical angiosperm ovule.
Ans:
Class XII Biology www.vedantu.com 2
