Sexual Reproduction in Flowering Plants

Sexual reproduction can be defined as the production of new progeny due to fusion of gametes called as sexual reproduction.

Characteristics features of sexual reproduction:

1) Formation of gametes takes place.

2) Two parents involved.

3) Sexual reproduction occurs when male gamete fuses with the female gamete that is fusion of gametes.

4) Sexual reproduction occurs in higher organism such as plants, animals and humans.

Diagram of flower showing reproductive organs

Process of sexual reproduction in flowering plants:

1) The sexual reproduction takes place in flowering plants. Flower is the reproductive organ for sexual reproduction.

2) Sexual reproduction in flowering plant occurs in two generations such as gametophytic generations and sporophytic generation.

3) The gametophytic generation involves a single set of chromosome called as haploid (n). Haploid denoted as “n”.

4) Sporophytic generation of the plants involves fusion of gametes and producing diploid state. Diploid can be denoted as (2n).

5) Both the generators are required for sexual reproduction. Therefore, the alteration n gametophytic and sporophyte generation called as sexual life cycle of flowering plant.

A) Sporophyte generation

Sporophyte generation is the major step in life cycle of flowering plants. Sporophyte generation involve spore producing parts of a plant. The female spore producing organ called as ovaries whereas the male spore producing organ called as anther. Therefore, sporophyte generation divided into two types :

1) Microsporogenesis:

i) The microsporogenesis is the formation or development of spore from the male organ called microsporogenesis.

ii) Male reproductive organ called as anther.

iii) The anther is a bilobed structure contains the pollen sac.

iv) This pollen sac contains sporogenous cell also called as microspore Mother Cell (MMC).

v) Each MMC (Microspore Mother Cell) by the process of meiosis gives rise to number of microspores.

2) Megasporogenesis:

i) Megasporogenesis can be defined as formation of megaspore from female reproductive organ called as megasporogenesis.

ii) The female reproductive organ called as ovaries.

iii) The ovule is present within ovaries, which releases the sporogeous cells called as Megaspore Mother Cell (MMC).

iv) The MMC (Megaspore Mother Cell) releases number of megaspore by the process of meiosis.

B) Gametophytic Generation:

Gametophytic generations involve formation of haploid gametes.

The haploid gametes which contains single set of chromosomes. The male gametophyte will lead to formation of male gamete and female gametophytic will lead to formation of female gamete. The male gamete is called as sperm (n) and female gamete called as egg (n). After the formation of male gamete, next stage is fertilization.

C) Fertilization:

Fertilization is the process of fusion of male and female gamete. The fertilization will occur with two sperms. When one sperm fertilizes the egg, it lead to formation of zygote and the develops into embryo. The other sperm (n) will unite with second nucleus (2n) and leads to formation of endosperm.

Question and Answers:

1.) What is sexual reproduction?

Answer: Sexual reproduction can be defined as the production of new progeny due to fusion of gametes called as sexual reproduction.

2.) What are the characteristic features of sexual reproduction?

Answer:

i) Formation of gametes takes place.

ii) Two parents involved.

iii) Sexual reproduction occurs when male gamete fuses with the female gamete that is fusion of gametes.

iv) Sexual reproduction occurs in higher organism such as plants, animals and humans.

 3.) What is gemetophytic generation?

Answer: Gametophytic generations involve formation of haploid gametes. The haploid gametes which contains single set of chromosomes. The male gametophyte will lead to formation of male gamete and female gametophytic will lead to formation of female gamete. The male gamete is called as sperm (n) and female gamete called as egg (n). After the formation of male gamete, next stage is fertilization.

4.) What is microsporogenesis?

Answer:

i). The microsporogenesis is the formation or development of spore from the male organ called microsporogenesis.

ii) Male reproductive organ called as anther.

iii) The anther is a bilobed structure contains the pollen sac.

iv) This pollen sac contains sporogenous cell also called as microspore Mother Cell (MMC).

v) Each MMC 9microspore Mother Cell) by the process of meiosis gives rise to number of microspores.

5.) What is megasporogenesis?

Answer:

i) Megasporogenesis can be defined as formation of megaspore from female reproductive organ called as megasporogenesis.

ii) The female reproductive organ called as ovaries.

iii) The ovule is present within ovaries, which releases the sporogeous cells called as Megaspore Mother Cell (MMC).

iv) The MMC (Megaspore Mother Cell) releases number of megaspore by the process of meiosis.

6.) What is fertilization?

Answer: Fertilization is the process of fusion of male and female gamete. The fertilization will occur with two sperms. When one sperm fertilizes the egg, it lead to formation of zygote and the develops into embryo. The other sperm (n) will unite with second nucleus (2n) and leads to formation of endosperm.


Leave a Reply

Your email address will not be published. Required fields are marked *

six − 4 =