Explain five stem modifications with examples. [5 MARKS]
Explain five stem modifications with examples. [5 MARKS]
1 Mark each
1. Rhizome
It is fleshy, non-green underground stem. It has distinct nodes and internodes. Adventitious roots arise from the lower side. Examples - ginger, turmeric, banana
2. Bulb
It is a highly condensed discoid stem. Its upper surface a terminal bud and many fleshy leaves are present. A cluster of adventitious roots arises from the base of the bulb. Examples - onions, lily
3. Tuber
Stem tuber is a swollen tip of an underground lateral Stem. It is covered by a rough skin with a number small nodes called eyes. Examples - potato, cassava
4. Runner
It is a creeping stem with long internodes, running horizontally on the soil surface. The nodes bear axillary buds, scale leaves, and adventitious roots. Examples - grasses, strawberries.
5. Stem tendrils
Stem or its branches get modified into a green thread-like leafless structures called tendrils which are meant for climbing. These may be branched or unbranched. Examples - grapevines
1 Mark each
1. Rhizome
It is fleshy, non-green underground stem. It has distinct nodes and internodes. Adventitious roots arise from the lower side. Examples - ginger, turmeric, banana
2. Bulb
It is a highly condensed discoid stem. Its upper surface a terminal bud and many fleshy leaves are present. A cluster of adventitious roots arises from the base of the bulb. Examples - onions, lily
3. Tuber
Stem tuber is a swollen tip of an underground lateral Stem. It is covered by a rough skin with a number small nodes called eyes. Examples - potato, cassava
4. Runner
It is a creeping stem with long internodes, running horizontally on the soil surface. The nodes bear axillary buds, scale leaves, and adventitious roots. Examples - grasses, strawberries.
5. Stem tendrils
Stem or its branches get modified into a green thread-like leafless structures called tendrils which are meant for climbing. These may be branched or unbranched. Examples - grapevines
