Question

Draw and label the parts of L. S of the flower.

Answer 1

Hint: Each flower has four whorls – calyx, corolla, androecium, and gynoecium.

Complete answer:

Fig. L. S of flower
A flower with all the four whorls is called a complete flower.
Calyx
- It is the outermost whorl of a flower composed of a number of lobes called sepals.
- When the sepals are free, the calyx is called polysepalous and when the sepals are fused, the calyx is called gamosepalous
- It is usually green or colored.
Corolla
- It is the second whorl of a flower composed of petals.
- When the petals are free the corolla is called polypetalous and when petals are fused, it is called gamopetalous.
- They are usually larger, brightly colored, and strongly scented which attracts insects for pollination.
Androecium
- It is the third whorl of a flower composed of stamens.
- The stamen represents the male reproductive organ consists of two parts – a thin slender stalk called filament and at the tip of which there is a bilobed box- like structure called the anther.
- The two anther lobes are connected with a tissue called connective.
Inside the anther, there are two pollen sacs enclosing pollen grains.
Gynoecium
- It is the innermost female reproductive whorl of the flower composed of carpels. Each carpel has three parts – ovary, style, and stigma.
- The ovary is the basal swollen portion of carpels.
- The style connects the ovary with the stigma and usually arises from the top of the ovary.
The stigma is usually placed on the style.

Note: Sometimes calyx and corolla are not distinguishable from one another and the whorl is this called perianth. The separate parts of the perianth are called tepal.