FRUITS
A fruit is fertilized ovary. Fruits may be divided into 3 main groups namely;
- Simple fruits.
These are formed from one flower in which the pistil consists of either one carpel or several carpels fused together.
- Aggregate fruits.
These are formed from one flower in which the pistil consists of several free carpels.E.g Rose fruit, Bryophyllum (collection of simple fruits).
- Multiple Fruits.
These are fruits formed from inflorescence flowers whereby ovaries fuse after fertilization.E.g Pineapple and jackfruit.
SIMPLE FRUITS
- Dry Indehiscent fruits
These are fruits which have a dry fruit wall (pericarp) and do not split open to release the seeds.
These include the following;
- An Achene-Is the simplest possible fruit and consists of one seed, surrounded by a dry pericarp which does not dehisce.Example;an achene of sun flower.
- A nut-Is similar to an achene but the pericarp is so hard and tough e.g. Cashew nut.
Many so called nuts are not biologically nuts.
- Caryopsis-Is an achene like fruit in the pericarp and the seed coat have become fused together .E.g. all members of the grass family.
Diagram of maize seed
- Cypsela-Is an achene in which the calyx above an inferior ovary has persisted and formed a parachute of hairs called pappus.It is found in plants like Bidens Pilosa(Black jack)
- Samara-Is an achene in which the pericarp has been extended to form one or more wings e.g. African rosewood, Jacaranda, combretum. etc.
- Dry dehiscent Fruits
These have a dry pericarp which splits open to release the seeds.
They include the following;
- Follicle-Is a dry fruit formed from one carpel which has one or more seeds and splits down one side only.E.g. Sodom apple.
Legume-Is a dry fruit formed from one carpel which contains several seeds and split down both sides (sutures)e.g. beans, pea plants
- Capsule-Is a dry fruit formed from two or more carpels which contains several seeds. It usually opens by longitudinal slits e.g. Dutchman’s pipe,Balsam, cotton.
- Schizocarp-Is a dry fruit with several seeds which breaks up into separate parts each containing one seede.g.Desmodium, sweetheart and cassia.
Diagram of a schizocarp
- succulent fruits
At least part of these fruit are fleshy and can be eaten e.g. mango, oranges etc.
Succulent fruits include the following
- Drupes.
Examples; mangoes, avocado, coconut
A drupe has a fruit wall or pericarp divided into 3 layers.
1)Epicarp-Is the outer skin.
2)Mezzocarp-Is the middle fleshy layer usually eaten.
3)Endocarp-Is the inner woody or fibrous layer that encloses the seed.
NB:All drupes have one seed in the centre of the fruit.
- Berries.
Examples; tomatoes, guavas, oranges etc
A berry has a pericarp divided into 3 layers but here the endocarp is also fleshy. Berries develop from flowers either with superior ovaries e.g. tomatoes and oranges or inferior ovaries e.g. guavas.
Difference between a drupe and a berry.
BERRY / DRUPEIt has one large seed in the center / It has so many small seeds
Develops from a superior ovary only / Develop from either superior ovary or inferior ovary
The endocarp of a drupe is woody and fibrous therefore it cannot be eaten / The endocarp of berries is fleshy and can be eaten
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