Both plants and animals are equally important to maintain the balance of the earth’s ecosystem. Plants have a major impact on the atmosphere as well as on other living beings. Every part of a plant such as leaves, stem, roots, flowers, and fruits play an essential role in the ecosystem.
Thus, it is worthwhile for you to gather in-depth knowledge about plants. In the following content, the discussion will be on one of the most important parts of plants called leaves, its types, and the difference between simple and compound leaves.
However, before differentiating simple and compound leaves, it is important to know about both types of leaves thoroughly.
As you know, leaves are commonly known as the “kitchen” of plants. This is because leaves perform photosynthesis that provides food for the entire plant body. Moreover, leaves are also used as the reservoirs of plants as it stores water and food.
Leaves are made of leaf blades or lamina, stipule, and petiole. However, depending on the different environmental conditions, they can modify the structure to adapt as per the environment. Different types of plants have various shapes, colours, arrangements, sizes, and patterns of leaves.
Due to this wide range of varieties, leaves can be categorised into two types- simple leaves and compound leaves.
A single leaf that can not be divided into any smaller unit or leaflet is called a simple leaf. This type of leaf joins the stem through petiole without further subdivision in them. True leaves are directly connected to the tree-bud.
Example: Pear, Maple, Hibiscus, Mango, Guava, Oregano, Black oak, etc.
Mainly, simple leaves have four parts. They are-
Leaf base is the expanded area where the stem and leaf connect.
Depending on the species of the plant, the position of stipule change. However, in major cases, these small bud-like structures are situated near the leaf base.
The petiole is the part that attaches leaves to the stems. Plants can have short, long, or no petiole.
Lamina or Leaf Blade
The green expanded part of a leaf is called lamina or leaf blade. This part consists of mesophyll that helps in performing photosynthesis.
The leaf blades of compound leave are divided into several smaller leaflets that connect the stem via petiole. Moreover, the leaf blades also divide completely along the mid-vein. The stem with such an arrangement of leaves is known as rachis, the modified version of mid-vein.
Example: Neem, Rose, Desert cotton, Horse chestnut, Buckeye, Baobab, Poison ivy, etc.
Broadly, compound leaves are classified into two types- pinnately compound leaves and palmately compound leaves.
Pinnately Compound Leaf
Pinnation means the formation of leaflets by dividing a leaf. This pinnate arrangement of leaflets can be evenly or oddly paired.
The leaflet arrangement in even-pinnate is cross-placed, and the rachis sprouts with two leaflets termed as paripinnate. Example: Tamarind, Candle bush, mahogany.
But the leaflet arrangement in odd-pinnate is opposite with the rachis sprouts with one leaflet, termed as imparipinnate. Example: Rose, Pecans, Acacia, etc.
The three major types of Pinnately Compound leaves are-
Unipinnate leaves have a regular leaflet arrangement on the rachis. Example: Azadirachta indica.
Other than the primary axis or rachis, bipinnate leaves have a secondary axis or rachis with leaflet arrangements. Example: Honeylocust, Mimosa pudica.
When bipinnate leaves replace the unipinnate leaves, they are called tripinnate leaves. Example: Moringa oleifera.
Palmately Compound Leaf
In palmately compound leaves, the leaflets grow from a single point of the petiole. As the leaflet arrangement looks like the fingers of palm, it is called palmate. Quadrifoliate, trifoliate, bifoliate, and unifoliate palmate arrangements can be seen in compound leaves.
Example: Clover, Chestnut, Citrus Limon, Buckeye, Citrus maxima, etc.
1. What is the primary difference between Simple and Compound Leaves?
Ans. The basic difference between these two types of leaves is that simple leaves contain a single blade, whereas the blade of compound leaves divides into multiple leaflets.
2. What are Simple Leaves with examples?
Ans. Simple leaves are single leaves that do not contain any sub-divided leaflets. Example: Mango, Oak, Guava, etc.
3. How do Compound Leaves look like?
Ans. Compound Leaves have multiple leaflets attached to the mid-vein with individual stalks.