What is a flower? Draw a typical flower and label its different parts.
A flower is a reproductive part of a plant. It helps in sexual reproduction as it has male parts and female parts.
A fully opened flower has the following parts:
Stalk—A flower is attached to the shoot by means of stalk or pedicel stalk. The tip of the stalk is swollen or flattened. This is called toms or thalamus or receptacle. The different parts of a flower are inserted on the thalamus. There are usually four whorls as Calyx
- Corolla (Petals)
- Androecium (stamens)
- Gynoecium (Carpels)
- Present on the thalamus.
1. Sepals (Calyx): These are the outermost part of the flower. These are leaf-like and green in colour. This is the outer covering of the flower and forms outer whorl in a flower. The Calyx (sepals) enclose the inner parts of the flower when it is a bud. It is protective in function.
2. Corolla (Petals): Petals form the second whorl inner to the sepals. These are usually coloured, gaudy, or white in colour and scented and give a sweet smell. The value of a flower is due to the attractive colour of the petals. These attract the insects for pollination.
3. Stamens (Androecium): The third whorls inner to the petals are stamens. This third whorl is called Androecium. These are the male parts of the flower. Each stamen is formed of a long narrow, hair-like structure called a filament. On its tip, it bears a rounded broad sac-like structure called the anther. Each anther has two anther lobes. Each anther lobe has two pollen sacs which have powdery mass called pollen grains.
4. Carpels (Gynoecium): Carpels are the innermost or fourth whorl in a flower. It is lodged on the thalamus and forms the female part of a flower. This whorl of carpels is called gynoecium. Each carpel or pistil has three parts,
- The lowermost, swollen part is an ovary. It is attached to the thalamus
- The middle part is a style which is narrow, thread-like
- Stigma: The style ends in a knob-like, a rounded structure which is sticky in nature to receive the pollen grains. The ovaries contain ovules which later turn into seeds after fertilization and the ovary wall forms the fruit sometimes the thalamus also becomes a part of the fruit as in apple.