NEET BIOLOGY

Detailed explanation-1: -Spines are also modified leaves. In cacti, spines are wholly transformed leaves that protect the plant from herbivores, radiate heat from the stem during the day, and collect and drip condensed water vapour during the cooler night.

Detailed explanation-2: -1: Types of modified leaves. A) Bracts, B) Spines, C) Reproductive leaves (e.g. Bryophyllum daigremontianum), D) Tendrils (e.g. cucumber), E) Storage (e.g. aloe), F) Trap leaves (e.g. Drosera anglica).

Detailed explanation-3: -Leaves can be modified in the form of spines that reduce water loss and also act as a defence. Some are modified into tendrils to provide support to the plant. Some leaves are thick that help in water storage. Some are modified to catch and digest insects.

Detailed explanation-4: -Spines are sharp, pointed structures on a plant and are modified leaves. They protect the plant from predators. An example of spines can be seen in the Opuntia plant where the minute leaves of axillary buds transform into spines. Another example is pineapple where the margin of leaves is modified into spines.