Question
Classify fruits into simple, aggregate, and composite types. Give two examples of each and explain the structural basis of the classification.
Solution — Step by Step
A fruit develops from the ovary of a flower after fertilisation. The ovary wall becomes the pericarp (fruit wall). Sometimes other floral parts (like the thalamus) also contribute — these are called false fruits (e.g., apple, where the fleshy part is the thalamus, not the ovary).
A simple fruit develops from a single ovary of a single flower. The ovary may have one or many carpels, but they are fused.
| Type | Description | Examples |
|---|---|---|
| Drupe | Single seed, stony endocarp | Mango, coconut, peach |
| Berry | Many seeds, fleshy pericarp | Tomato, grape, banana |
| Pome | Fleshy thalamus, seeds in core | Apple, pear |
| Legume/Pod | Dehiscent, splits open | Pea, bean |
| Capsule | Dry, many seeds | Cotton, lady’s finger |
An aggregate fruit develops from a flower with multiple free carpels (apocarpous gynoecium). Each carpel forms a fruitlet; all fruitlets cluster together.
Examples: Raspberry (aggregate of drupelets), Strawberry (aggregate of achenes on a fleshy thalamus — also a false fruit), Custard apple (Annona).
A composite (multiple) fruit develops from an entire inflorescence — all the flowers fuse together into one structure.
Examples: Pineapple (from a spike inflorescence — called a sorosis), Fig (from a hollow receptacle enclosing flowers — called a syconus), Mulberry (sorosis), Jackfruit (sorosis).
flowchart TD
A[Fruit Classification] --> B[Simple]
A --> C[Aggregate]
A --> D[Composite/Multiple]
B --> B1[One ovary, one flower]
B --> B2[Mango, Tomato, Pea]
C --> C1[Multiple free carpels, one flower]
C --> C2[Raspberry, Custard apple]
D --> D1[Entire inflorescence]
D --> D2[Pineapple, Fig, Jackfruit]Why This Works
The classification is based on the number of ovaries and flowers involved. One ovary = simple. Many free ovaries from one flower = aggregate. Many flowers contributing = composite. This structural logic makes the classification easy to remember.
Common Mistake
Students classify apple as a simple fruit. While the ovary is simple, the fleshy edible part of an apple is the thalamus (not the ovary wall). This makes apple a false fruit (pseudocarp). The true fruit is the core with seeds.
Quick memory trick: Pineapple = composite (many flowers), Custard apple = aggregate (many carpels, one flower), Apple = simple false fruit (one ovary, thalamus is edible).