Leaves are important parts of the plants. They carry out photosynthesis, storing food and water. Leaves can be of different shapes, sizes, colors and arrangements as well as patterns. Leaf-blade or lamina, petiole, and the stipule are parts of a leaf. Leaf-blade or lamina is a large portion and is attached to the petiole and further extended to the stem. Axil is another point where the petiole joins the stem, whereas the stipule is present at the leaf base. These are the small bud-like structure.
The characteristics of the leaves may vary in different places due to environmental conditions. Leaves can become modified and show adaptations according to the environment. Different patterns and shapes of the leaves help in the identification of the plant’s species.
Simple and compound leaves are the types of leaves based on their shape. Simple leaves have a single blade and incision, which are so light that does not divide the leaf blade whereas, in compound leaves, an incision is so deep that the leaf blades are divided into the leaflets.
|Basis for Comparison||Simple leaves||Compound leaves|
|Definition||The simple leaf is defined as a single leaf that is never divided into the smaller leaflet units.||The compound leafis defined as a leaf consisting of several or many distinct parts joined to a single stem.|
|Stipules||The base of the leaf may have stipules||May occur at the base of the whole leaf|
|Lateral buds||At the base of the petiole||No lateral buds found at the base of each leaflet|
|Leaf-blade||Not divided into smaller, individual leaflets||Divided into smaller, individual leaflets|
|Division in lamina||No division in the lamina||Division in the lamina|
|Axillary bud||Placed in the axil (near the petiole and stem)||Do not have axil, though the buds are placed in the axil of the leaf.|
|Examples||Black gum trees, black cherry trees, Guava, Mangoes, etc||Neem, rose, shame plant, and buckeye.|
What are Simple leaves?
A simple leaf is called simple as it is never divided into smaller leaflets. Simple lead is always attached to the twig by its stem or the petiole. Its margins, edges can be smooth, lobed, jagged, or parted. There are many examples of leaves with a simple pattern; pear plants, hibiscus, oregano, maples, scarlet oak, and black oak.
What are Compound leaves?
A compound leaf has many leaflets joint to the stem through petiole and exhibits the complete division of the lamina or leaf blade along the midrib. The stem on which this arrangement occurs is called the rachis. It is a modified mid vein. Many plants that show this type of pinnation pattern, such as rose, neem, desert cotton, and baobab.
Compound leaves are broadly classified into two types; pinnately compound leaves and palmately compound leaves.
- Pinnately Compound Leaves: The term “pinnation” means the sub-division of a leaf into leaflets. The pinnate leaflet arrangement of compound leaves can be either evenly paired or oddly paired.
In even pinnate leaflet arrangement, the pattern of the leaflets is oppositely, and the rachis at the end are sprout with two leaflets known as paripinnate. Leaves of candle bush and mahogany and tamarind show even pinnate leaflet arrangement.
In odd-pinnate leaflet arrangement, the leaflet pattern is oppositely, but the rachis at the end are sprout with the single leaflet, which is known as imparipinnate. Leaves of rose, pecans, and acacia show this type of pattern.
Pinnately compound leaves are further divided into three types based on the pinnation pattern; unippinate, bipinnate and tripinnate.
- Unipinnate: This is the regular arrangement of leaflets on the rachis. Azadirachte indica shows this type of arrangement.
- Bipinnate: This is also known as twice pinnate or double pinnate. In this arrangement, there is a secondary rachis or axis on which the leaflets are arranged apart from the main rachis. The leaves of mimosa pudica and honeylocus shows this arrangement.
- Tripinnate: In this type of arrangement, the leaflets are bipinnate leaves and so-called tripinnate leaves. The example of tripinnate leaves are leaves of Moringa oleifera.
- Palmately Compound Leaves: The leaflets start from the single point of the petiole is called palmately compound leaves. The leaflets pattern is similar to the fingers of the palm and so the leaves got the name as palmate.
Palmately compound leaves are classified as unifoliate, trifoliate and quadrifoliate. The trees of citrus maxima, citrus limon, hauhinia, yunnanesis, chestnut, oxalis, marsilea and clover shows leaves on this pattern.
- Simple leaves have leaf blade or lamina undivided into lobes and are directly attached to the stem even the arrangement of such leaves is in acropetal succession. In contrast, compound leaves have a proper division of leaf blade or lamina into leaflets which terminate with the single or double leaflets.
- Simple leaves have single lamina or leaf blade, whereas compound leaves have smaller and separate leaf blades called leaflets.
- Simple leaves have stipules at the base, whereas the compound leaves also have stipules at the base but lack additional structures.
- In simple leaf, lateral bud occurs at the base of the petiole, whereas in compound leaf, there is no bud at the bottom of each leaflet.
- Examples of simple leaves plants are black cherry trees, black gum trees, guava, mangoes and oaks, whereas compound leaves plants are rose, shameplant, neem and buckeye.
- Both simple and compound leaves are characteristics of in dicot plants.
- Both simple and compound leaves perform photosynthesis for the plants.
- Both contain a broad lamina.
- Both types of leaves have lamina, petiole and stipule as their components.
- Both types of leaves show adaptation to the habitat where the plants live.
In conclusion, simple and compound leaves differ from each other based on shape. Simple leaves do not have further leaflets, whereas compound leaves have leaflets. Both types of leaves perform the same function for the plants.