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Although most of
are found of fruits and vegetables
and also love to eat them, it would
be difficult to give a definition
for fruit. In botanist term the definition
is easier; “a fruit is a reproductive
structure of an angiosperm which develops
from the ovary and accessory tissue,
which surrounds and protects the seed”.
Fruits are important in seed dispersal.
It does not matter  what
we may call our nutritious dietary
components, in botany what constitutes
a fruit is quite straightforward,
and this lab looks at the structure
and classification of fruits.
The process of fertilization carries
both seed and fruit development. While
the seeds develop from ovules, the
ovary tissue undergoes a number of
series complex changes which result
in the development of the good and
fresh fruit. Many fruits are "fleshy"
and contain sugars which attract animals
that then disperse the enclosed seeds
to the new locations. Other, non-fleshy,
fruits use other mechanisms for seed
dispersal.
Fruits can be classified
in to four types as follows:
v
Simple
Fruits
v
Compound Fruits
v
Accessory
Fruits
 Simple
Fruits
Simple fruits could be either dry
or fleshy and result from the ripening
of a compound or simple ovary with
only one pistil. Dry fruits could
also be either dehiscent (opening
to discharge seeds), or indehiscent
(not opening to discharge seeds).
Aggregate
Fruits
An aggregate fruit is otherwise called
as etgerio, develops from a flower
with the numerous simple pistils.
A good example is raspberry, whose
simple fruits are termed drupelets
because each is like a good small
drupe attached to receptacle. In some
of the bramble fruits (example blackberry)
the receptacle is elongate and part
of the ripe fruits, for making blackberry
an aggregate-accessory fruit.
Multiple
Fruits
A multiple fruit is formed from a
cluster of flowers called an inflorescence.
Each flower does produce a fruit,
but these mature into a single mass.
Examples are mulberry, pineapple,
and breadfruit.
Accessory
Fruits
Accessory fruits are composed of material
not just form the ovary but also participate
to form other parts of the flower
such as the receptacle. To understand
even better an accessory fruit is
a fruit where the fleshy part is derived
not form the ovary but form some adjacent
tissue
Few very good examples of accessory
fruits are strawberry, watermelon,
apple etc. Most accessory fruits are
simple fruits that are developed from
inferior ovaries.
The following table
describes the major types
of fruits:
Simple
Fruits
(derived from a single ovary) |
Pericarp
Fleshy |
Pericarp
Indehiscent
(does not split open when ripe) |
Pericarp
Dehiscent
(splits open when ripe) |
| Drupe, Pome,
Berry, Pepo |
Akene, Nut, Caryopsis |
Legume,
Silique, Capsule, Follicle |
Multiple
Fruit
(derived from the ovaries
of several flowers united into
a single mass) |
Strawberry,
Blackberry, Rraspberry |
Aggregate
Fruit
(derived from numerous ovaries
of a single flower that are scattered
over a single receptacle and later
unite to form a single fruit) |
Pineapple |
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Classification
