Morphology: root, stem, leaf and modifications
- Identify the correct set of statements :(a) The leaflets are modified into pointed hard thorns in Citrus and Bougainvillea(b) Axillary buds form slender and spirally coiled tendrils in cucumber and pumpkin(c) Stem is flattened and fleshy in Opuntia a… Answer: 4. (b), (c), (d) and (e) Only (a) In Citrus and Bougainvillea, axillary buds (stems) become thorns, not leaflets: false. (b) Axillar... 1
- The roots that originate from the base of the stem are : Answer: 1. Fibrous roots Key idea: Roots arising from the base of the stem are adventitious and, in monocots, form a fibrous root system. In... 1
- Sweet potato is a modified Answer: 3. Adventitious root Sweet potato is a root that stores food, and it arises from a non-root part, so it is an adventitious root. Tap... 1
- Pneumatophores occur in Answer: 1. Halophytes Pneumatophores are breathing roots that grow upward out of waterlogged, salty soil. They are found in mangrove plants... 1
- In Bougainvillea thorns are the modifications of : Answer: 2. Stem The thorns of Bougainvillea are modified stems (axillary buds changed into hard, pointed thorns). They protect the plant fro... 1
- Root hairs develop from the region of : Answer: 4. Maturation Key idea: Root zones from tip upward: root cap, meristematic, elongation, maturation. Cells in the maturation zone dif... 1
- Stems modified into flat green organs performing the functions of leaves are known as : Answer: 3. Phylloclades Flat, green stems that do the work of leaves (photosynthesis) are phylloclades, e.g. Opuntia. Cladodes: short stem b... 1
- Which of the following is not a stem modification ? Answer: 1. Pitcher of Nepenthes The pitcher of Nepenthes is a modified leaf, not a stem. Thorns of citrus: modified axillary buds (stem). Te... 1