Key differences in structure examples and diagram of pinnate and palmate compound leaves
Leaves are an essential part of plants. They photosynthesise and produce food for plants. Leaves are mainly of two types, simple and compound leaves. Compound leaves are further classified into two types, mainly pinnately and palmate compound leaves. When we surround ourselves with nature, we are mesmerised by the bright green colour which strikes our eyes. This green colour comes from leaves. Leaves are born on the stem and rise at nodes. Have you ever thought about where the green colours on leaves come from?
Chlorophylls absorb light which allows plants to collect energy from the Sun. As a result, leaves are green because chlorophylls absorb every colour of UV light except for the green colour. When you look closer at leaves have you ever noticed how different they are in shape, size, and texture? There exists a wide diversity between leaves. There are some general characteristics between them but some have unique abilities.
Leaves are built from three main types: the base, the blade, and the petiole. The longest part of the leaf is the blade. The base is known as the region of the blade that attaches to the petiole.
Types of Leaves
Simple Leaves – Simple leaves possess the entire lamina. Even if the lamina is carved, it does not reach the midrib. They do not have leaflets.
Compound Leaves – Compound leaves possess leaflets. The lamina of a leaf is divided into many leaflets and blades.
Simple Leaf
Compound Leaf
What is a Simple Leaf?
A leaf that can not be further divided into any smaller sections or leaflets is called a simple leaf. This type of leaf joins the stem through the petiole.
Structure of Simple Leaves:
Simple leaves consist of four parts:
Leaf Base - It is the expanded area where the stem and leaf connect.
Stipules - The position of the stipule changes depending on the species of the plant. These small bud-like structures are situated near the leaf base.
Petiole - The petiole is the part that adheres the leaves to the stems. Plants can have short, long, or no petioles at all.
Lamina or Leaf Blade - The green extended part of a leaf is called the lamina or leaf blade. This part consists of mesophyll that helps in performing photosynthesis.
What is a Compound Leaf?
Compound leaves are those leaves when the lamina of a leaf is divided into many leaflets. The incision made in the lamina is reached into the midrib which is further divided into multiple leaflets. The leaflets in the compound leaf do not possess buds in their axes.
Compound leaves are of two types:
Pinnate Compound Leaves
Palmate compound leaves
Pinnately Compound Leaf with Examples
In pinnate compound leaves, leaflets are present on the common axis. The midrib is represented by the common axis called the rachis.
Examples: Ash, Hickory, Walnut, Pecan, Black lotus, Neem, Cassia fistula.
There exist three types of pinnate leaf arrangement:
Even-pinnate Leaflet Arrangement: In this arrangement, leaflets are in pairs along the rachis without a single terminal leaflet. This type of arrangement is also known as paripinnate.
Odd-pinnate Leaflet Arrangement: In this arrangement, instead of a terminal pair of leaflets, there is a single terminal leaflet at the top. This type of arrangement is also known as imparipinnate.
Alternate-pinnately Leaflet Arrangement: In this type of arrangement, leaflets are produced alternately along the rachis with a single terminal leaflet. This type of arrangement is also known as aternipinnada.
Pinnate Compound Leaves and Types
Bipinnately and Tripinnately Compound Leaves
Pinnately leaves that further divide are called bipinnately compound leaves. These compound leaves have leaflets from secondary rachises. The axillary buds are actually found in the angle between the petiole and the stem of pinnate leaves, not in the axils of leaflets is the main distinguishing factor to recognize bipinnate leaves.
Even if these leaflets are twice or thrice divided, they all still account for one leaf branching off the stem. Since the leaflets are formed on primary and secondary veins, the leaflets formed are given the name pinna.
Palmately Compound Leaf with Examples
In simple palmate leaf, the leaflets are formed and arise from a single point of attachment called the distal end of the rachis.
Each leaf is a part of an individual leaf and all are branching from the axil part of the leaf. These compound leaves do not have rachises as each palmate branches out directly from the petiole, each petiole may also branch off to other petioles.
Examples: Clover, potentilla indica, oxalis, Silk, and Cotton.
Difference Between Pinnately and Palmately Compound Leaf
Interesting Facts
Leaf cells consist of organelles known as chloroplasts which contain specialised pigments called chlorophyll.
Since leaves do not absorb green colour, they instead reflect it which is seen by our eyes.
Important Questions
What are the two types of compound leaves?
Ans: The two types of compound leaves are pinnately and palmately compound leaves. In pinnately compound leaves, leaflets are present on the common axis and in palmately compound leaves, leaflets are present on the distal end of the rachis.
What are the various parts of the leaves?
Ans: The various parts of the leaves are midribs, axil, stem, leaf base, petioles, vein, venules, tip, and leaf base. Each part of the leaf has a function that is used in the function of the leaves.
Key Features
Just like the name of the palmately compound leaves, the whole leaf is shaped like the palm and fingers of your hand.
Pinnately leaves show the resemblance of a feather.
FAQs on Difference Between Pinnate and Palmate Leaves Explained
1. What is the difference between pinnate and palmate compound leaves?
The main difference between pinnate and palmate compound leaves is the arrangement of leaflets on the petiole. In pinnate compound leaves, leaflets are arranged along a central axis called the rachis, whereas in palmate compound leaves, all leaflets arise from a single point at the tip of the petiole.
- Pinnate compound leaf: Leaflets attached on both sides of a rachis (feather-like).
- Palmate compound leaf: Leaflets spread out from one point like fingers of a hand.
- Both are types of compound leaves, meaning the blade is divided into separate leaflets.
2. What is a pinnate compound leaf?
A pinnate compound leaf is a type of compound leaf in which leaflets are arranged on either side of a central axis called the rachis. This arrangement resembles a feather.
- The rachis is an extension of the petiole.
- Leaflets are attached laterally along the rachis.
- Example: Neem (Azadirachta indica) and rose.
3. What is a palmate compound leaf?
A palmate compound leaf is a compound leaf in which all leaflets arise from a single point at the end of the petiole. The arrangement looks like the palm of a hand with spreading fingers.
- No rachis is present.
- Leaflets radiate from one common point.
- Example: Bombax and Trifolium (clover).
4. What are examples of pinnate and palmate compound leaves?
Common examples of pinnate and palmate compound leaves help in understanding their structural differences.
- Pinnate compound leaves: Neem, rose, tamarind.
- Palmate compound leaves: Silk cotton (Bombax), clover, lupin.
- The key identifying feature is the presence or absence of a rachis.
5. How can you identify a pinnate compound leaf?
A pinnate compound leaf can be identified by the presence of a central rachis with leaflets arranged on both sides. It has a feather-like appearance.
- Look for a main axis extending from the petiole.
- Check if leaflets are attached along this axis.
- Each leaflet does not have an axillary bud at its base.
6. How can you identify a palmate compound leaf?
A palmate compound leaf can be identified when all leaflets originate from a single point at the tip of the petiole. It resembles an open palm.
- No elongated rachis is present.
- Leaflets spread radially from one common point.
- Common in plants like Bombax and clover.
7. What is the function of pinnate and palmate compound leaves?
The primary function of both pinnate and palmate compound leaves is photosynthesis, along with transpiration and gas exchange. Their divided structure provides additional advantages.
- Increases surface area for photosynthesis.
- Allows better air circulation between leaflets.
- Reduces damage from wind due to flexible leaflets.
8. What is the difference between a simple leaf and a compound leaf?
The difference between a simple leaf and a compound leaf is that a simple leaf has a single undivided lamina, while a compound leaf has its lamina divided into separate leaflets.
- Simple leaf: One blade, e.g., mango.
- Compound leaf: Blade divided into leaflets, e.g., neem.
- In compound leaves, leaflets lack axillary buds at their base.
9. Are pinnate and palmate leaves types of compound leaves?
Yes, both pinnate and palmate leaves are types of compound leaves. They differ only in the arrangement of their leaflets.
- Both have multiple leaflets forming one leaf.
- The axillary bud is present at the base of the whole leaf, not individual leaflets.
- They are classified based on leaflet arrangement pattern.
10. Why are compound leaves divided into pinnate and palmate types?
Compound leaves are divided into pinnate and palmate types based on the pattern of leaflet arrangement. This classification helps in plant identification and taxonomy.
- Pinnate: Leaflets arranged along a rachis.
- Palmate: Leaflets arise from a single point.
- This structural difference is important in plant morphology and classification.
