Hint: Leaf, the normally flattened green outgrowth of a vascular plant's stem. Leaves provide food for plants as the main photosynthesis sites, which in turn eventually nourish and support all land animals.
- Leaves are an important part of the stem system in botanical terms. They are connected to the rest of the plant by a continuous vascular system so that free exchange of nutrients , water, and photosynthesis end products (in particular oxygen and carbohydrates) can be carried to its various parts.
- In the apical bud (growing tip of a stem), leaves are initiated along with the stem tissues themselves.
- The sharp spines of cacti, the needles of pines and other conifers, and the scales of an asparagus stalk or a lily bulb are some of the organs that are superficially very different from the normal green leaves that are shaped in the same manner and are actually modified leaves.
- A leaf usually consists of a broad expanded blade (the lamina), connected by a stalk like petiole to the plant stem.
- Leaves usually have a pair of structures known as stipules in angiosperms, which are situated on either side of the base of the leaf and may resemble scales, spines, glands, or leaflike structures. However, in size , shape, and various other characteristics, leaves are quite diverse, including the nature of the blade margin and the type of venation.
- The main function of a leaf is photosynthesis to provide food for the plant. The material that gives plants their characteristic green colour, chlorophyll, absorbs light energy.
- The role of the stomata is to allow the leaf to move in and out with water vapour and gases. Also, the stomata are responsible for the transpiration process, the rate at which water is lost by a plant. Via the stomata, air reaches into the plant.
The correct answer is option (A) Transpiration and Photosynthesis.
Note: Whole leaves or sections of leaves are also modified for special purposes, such as climbing and attaching substrates, storage, defence from predation or climatic conditions, or insect prey trapping and digesting.