The origin of the friut is the ovary of the flower. After fertilisation the ovary forms the friut. As is commonly known, fruits vary widely, and thuis have to be classified.
Occasionally the pericarp develops from the ovary wall and adjacent structures usually the receptacle. It is difficult to decide whether the structure is a seed or fruit. In such cases the number of scars on the structure should be counted. A seed usually has one scar where it was attached to the placenta whereas a fruit will usually have two scars, one where it was attached to the receptacle and the other representing the remains of style of stigma. After fertilization the female part or gynaecuim matures to form a fruit and the sepals, petals, stamen, style and stigma wither and usually fall off. The ovary wall changes to become either hard and dry or soft and fleshy. The fruit is therefore the structure, which develops as a result of fertilization, and it contains the seeds.
Fruits may be classified in various ways. Often they are divided into three main groups.
Simple fruits which are formed from one flower in which the pistil consist of either one carpel ( monocarpous) or of several fused together (syncarpous).
Aggregate fruits, which are formed from one flower in which the pistil consists of several free carpels (Apocarpous).
Multiple fruits which are basically formed from several parts of a flower that is other parts of the flower become fused after fertilization.
1;Dry Indehiscent fruits, which consist of one seed surrounded by a dry pericarp, which does not split .
Under these we have, achenes, nuts,caryopsis, cypsela, samara.
Achenes: consist of one seed surrounded by a dry pericarp which does not split or dehisce. An example is a sunflower.
A nut: it is similar tto an achene but the pericarp is very hard and tough . An example is a cashew nut. Many so called nuts are not boilogical nuts,....for example a coconut.
A cryopsis; it is an achene-like fruit in which the pericarp and seed coat have become fused together. it is typical for grasses or cereals like maize.
A cypsela is an achene in which the calyx above an inferior ovary has persisted and formed a parachute of hair called pappus it is formed in many composite for example tridax and Bidens.
2:Dry dehiscent fruits
In these fruits the pericap splits open to set the seeds free. They are usually classified according to the number of splits, which occur in the pericap.
A follicle: is a dry fruit formed from one carpel which has one or
more seeds and splits down one side only for example Sodom apple and oleander.
A schizocarp is dry several seeded fruit which breaks up into separate
parts each containing one seed for example desmodium
These fruits are usually fleshy and this is usually the pericap. Succulent fruits are divided into two groups.
These include drupes and Berries.
Drupes:In the drupes part of the pericap can be eaten while in berries the whole pericap can be eaten that is it is fleshy.
A mango is a drupe. The pericap is represented by the thin yellow outer coating. The mesocarp is the fleshy part which is eaten and the part discarded is the endocarp. Other example of Drupes include oil palm and coconut fruits. Though there are exceptions due to their fibrous mesocarp. Drupes are developed from flowers with superior ovaries.
Multiples fruits are formed from an inflorescence from many flowers
for example pineapple and a fig. A fig is formed from the end of the stalk
from the inflorescence, which is greatly enlarged and contains a cavity
opening by a small hole at the top. Inside the cavity the male and female
flowers develop and later the female flowers ripen into small fruits.
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