What is a flower? Describe the parts of typical angiosperm plants
The flower is a modified shoot with nodes and modified floral leaves. The parts of typical angiosperm plants are: - i. Calyx (Sepals): - It is the green outer whorl of the flower. The members of the calyx are termed sepals. It is a leaf-like structure. It performs an important role in the protection of the flower in the bud stage. It may be ‘polysepalous’ i.e., sepals free or ‘gamosepalous’ i.e., sepals united. ii. Corolla (Petals): - It is the second whorl of the flower situated inside the sepals. The petals are usually bright and colourful. The insects are attracted to the brightly coloured petals so they add in pollination. The lower, stalk-like portion of the petal is known as a claw. The upper, extended portion is known as a limb. iii. Androecium (male reproductive part): - Androecium, a male reproductive part of a flower, consists of the stamen. Each stamen is made up of two parts: Filament and Anther. a) Anther: - It is a bilobed structure. Each anther lobe contains two pollen sacs. Pollen sacs produce pollen grains. b) Filament: - It is a stalk-like structure by which anther lobes are attached is called a filament. iv. Gynoecium (female reproductive part): - It is made up of one or more carpels. A carpel consists of 3 parts: - Stigma, Style and Ovary. a) Stigma: - Stigma is the uppermost part of the pistil and is the receptive surface for pollen grains. b) Style: - It is a stalk-like structure that connects the stigma to the ovary. c) Ovary: - The basal part that bears one or more ovules attached to a flattened cushion-like placenta.
