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Stamen is the male reproductive organ of the plant which consists of an anther and a filament. Anther produces male gametes in the pollen grains. The anthers release the pollens which fertilize the eggs after pollination. Carpel is the female reproductive organ of the plant which consists of the stigma, the style and the ovary. The stigma is sticky and receives pollens. Ovary contains ovules which has female gametes (eggs). After pollination on stigma, pollen is sent to ovary. The fertilization of male gamete and female gamete takes place within the ovule which becomes a seed and ovary becomes the fruit.

1. The pollen grains which fall on the stigma of a flower germinates. 

2. A pollen tube is formed from the pollen grains. 

3. The pollen tube travels from stigma to the ovules in the ovary. 

4. Fertilization and zygote formation occur in ovary. 

5. The zygote develops into an embryo.

1. After fertilization, the ovary ripens and turns into fruit. ’ 

2. The remaining floral parts will fall off. 

3. The ovules become the seeds.

After fertilization the ovary ripens and grows into a fruit.

Fertilization : Fusion of male and female gametes to form zygote is called fertilization. This is the process of formation of zygote.

Self-Pollination:

(a) Pollen grains are transferred to the stigma of the same flower.
(b) Occurs in bisexual plants having anther and stigma maturing at the same time.
(c) It takes place in plants like wheat, peas etc.

Cross-Pollination:

(a) Pollen grains are carried to the stigma of another flower.
(b) Occurs in bisexual flowers having anther and stigma maturing at different times.
(c) It takes place in plants like lady-finger, tomato, brinjal etc.

Following are the ways by which the seeds are dispersed:

• Some light seeds like that of madar, which are hairy, dry and small are carried away by the wind to different places.
• Spiny seeds and fruits like that of. Xanthium and Urena, stick to the clothes of passers-by and animals. These seeds are carried away by these agents to different places.
• In some plants having heavy seeds like that of coconut, water acts as the dispersing agents.
• Some seeds are dispersed when the fruits burst like, in case of balsam and castor.

The process of pollen grains reaching the stigma from another is known as pollination.

Megaspore mother cell undergoes the normal meiosis and four megaspores formed gradually disappear. A nucellar cell becomes activated and develops into a diploid embryo sac. This type of apospory is also called somatic apospory. Examples Hieracium and Parthenium.

Tenuinucellate Ovule: 

1. Ovules with hypodermal sporogerous cell with unilayerd nucellus tissue is  called tenuinucellate type.

2. They have very small nucellus

Crassinucellate Ovule: 

1. Ovule with subhypodermal sporogenous cell is called crassinucellate type. 

2. They have large nucellus

(a) Statement 1 is correct and statement 2 is incorrect.

In some plants, fruits develop from ovary without fertilization process. Such fruits are called parthenocarpic fruits. They lack true seeds.

Exine: 

1. Thick outer layers

2. It is made of cellulose, sporopollenin and pollenkitt. 

3. Ununiform layer

Intine: 

1. Thin inner layer 

2. It is made up of pectin, hemicellulose, cellulose and callose 

3. Uniform layer

In some plants, all the microspores in a microsporangium remain held together called / poilinium. 

Example: Calotropis.

(b) Tetrasporangiate

Correct Answer is: (c) Tapetum

Correct Answer : (d) iv only

When the pollen grain reaches the stigma of the same species flower, it starts growing out into the pollen tube of the stigma. This tube continues to grow inside the style until it reaches the ovule. Male cells are released into the ovule for the fertilization with the female egg cell and thus the zygote is formed. After this process of fertilization, the ovary develops into fruit and ovule into seeds.

Unisexual flowers that contain only androecium are called male flowers.

The flower consists of four parts. Sepal, Petal, Stamen and Pistil.

Unisexual flowers that contain only gynoecium are called female flowers.

The flowers which have both androecium and gynoecium is called bisexual flowers.

Anther wall : The mature anther wall consists of the following layers

a. Epidermis 

b. Endothecium

c. Middle layers 

d. Tapetum.

a. Epidermis: It is single layered and protective in function. The cells undergo repeated anticlinal divisions to cope up with the rapidly enlarging internal tissues.

b. Endothecium: It is generally a single layer of radially elongated cells found below the epidermis. The inner tangential wall develops bands (sometimes radial walls also) of a cellulose (sometimes also slightly lignified). The cells are hygroscopic. In the anthers of aquatic plants, saprophytes, cleistogamous flowers and extreme parasites endothecial differentiation is absent. The cells along the junction of the two sporangia of an anther lobe lack these thickenings. This region is called stomium. This region along with the hygroscopic nature of endothecium helps in the dehiscence of anther at maturity.

c. Middle layers: Two to three layers of cells next to endothecium constitute middle layers. They are generally ephemeral. They disintegrate or get crushed during maturity.

d. Tapetum: It is the innermost layer of anther wall and attains its maximum development at the tetrad stage of microsporogenesis. It is derived partly from the peripheral wall layer and partly from the connective tissue of the anther lining the anther locule. Thus, the tapetum is dual in origin. It nourishes the developing sporogenous tissue, microspore mother cells andmicrospores.

The cells of the tapetum may remain uninucleate or may contain more than one nucleus or the nucleus may become polyploid. It also contributes to the wall materials, sporopollenin, pollenkitt, tryphine and number of proteins that control incompatibility reaction .Tapetum also controls the fertility of sterility of the microspores or pollen grains.

Pectin, cellulose, hemicellulose, callose, sporopollenin, pollenkitt and other proteins.

Correct Answer : (d) Tapetum

(b) R explains A.

(c) Epidermis → endothelium → middle layers → tapetum

Correct Answer is: (d) seed

(a) Sporogenous cell is hypodermal

(d) G.B.Amici

(a) Epidermis 

(b) Endothecium 

(c) Middle layers 

(d) Tapetum

(b) Embryo sac

(c) Nucellus – nutritive tissue for developing embryo

Based on the presence and absence of floral parts flowers are two types: 

(i) Complete flower

(ii) Incomplete flower.

Based on the presence of both or single sexual parts flowers are of two types:

(i) Bisexual flowers

(ii) Unisexual flowers

(d) More than one option is correct

(b) 2 celled stage

In general, the pollen grains are liberated at 2 – celled stage. On reaching the stigma at this stage, the generative cell divides meiotically and form two male gametes (male cells)

(b) G.B. Amici

(a) 10 micrometer

(c) Stylar region of gynoecium

(a) Microspore

(d) Tapetum, middle layers endothecium epidermis

The correct option is C) Tomato.

1. Animals, birds and human beings eat these fruits and the seeds are thrown away. 

2. Like that way, seeds will be dispersed to different places. 

3. For the purpose of reproduction many fruits are sweet and fleshy,

The correct option is A) Plants.

The correct option is B) Water.

The correct option is D) Water.

(b) Entamophily

(d) Synergids