A leaf can be defined as a plant-organ above the ground. A typical leaf is laminar and thin and the main function of the leaves is
photosynthesis. A leaf cell contains chloroplast that is exposed to light to initiate the process of photosynthesis. Other important functions include storage of food and water. However, in some plants the functions of the leaves are modified for certain other purposes. A few of the leaf types are vegetables included in the human diet.
Types of Leaves
There are different kinds of leaf types. The leaves are classified as simple leaves and compound leaves.
When as leaf has only a single leaf blade on its stalk it is known as a simple leaf. The stalk of a simple leaf is attached to the plant body. There is a scar left on the plant body when a stalk is removed from it.
When a leaf has more than one leaf blade on a stalk it is called a compound leaf. The multiple leaf blades are known as leaflets. The leaflets together make a single leaf that is attached to a single stalk. Like a simple leaf, the stalk of a compound leaf is also attached to the plant body and it leaves a scar mark on the plant body when it is removed from the stem.
Different Kinds of Leaves
Two major kinds of leaves commonly found are the
broad and flat and
needle and scale.
A broad and flat leaf is seasonal leaf. A broad leaf is green during the spring season. By the end of summer, the color of broad leaves changes and the plants and trees drop them.
This kind of leaves are found in "evergreen" trees. The "evergreen" trees hold these leaves throughout the winter season. The lengths of this needle-like leaves vary in lengths. The needles grow either singly or in bundles. Most of the needles are narrow and pointed. Scale leaves are often short and flat, and lie close to the plant stem.
Given below are a few different kinds of leaves
The length of a lanceolate leaf is greater than its width. A leaf of this kind has the shape of a lance - broad at the base and narrow towards the apex. An example of this leaf type is green ash.
An ovate leaf is oval in shape. The middle of the leaf is the broadest. An example of an ovate leaf is flowering dogwood.
An oblong leaf has parallel sides. The leaf has a rectangular shape with rounded corners. An example of this kind of leaf is willow.
There are many different kinds of leaves. You can identify the category of a tree by checking out their leaf type. For instance, if the leaves grow on the opposite sides of a twig, there is a possibility of the tree being a dogwood or a maple tree.
