22 Biology -- Angiosperm

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Fruit


Fruit is regarded as the ripen ovary with seeds  covered by pericarp.

Classification :

On the basis of origin :

1.   True  fruit

2.   False fruit

3.   Parthenocarpic fruit

·       True fruit : It develops from ovary  where ovule forms seeds and wall of ovary matures as pericarp. They are mainly result of superior ovary.

 

Eg : Mango,Tomato, Pea,Coconut

 

·       False / pseudo  fruit : fleshy and edible portion of fruit develops from receptacle or thalamus and not from the wall of ovary. They are result of  mostly inferior ovary.

Eg : apple

·       Partheno carpic fruit : fruit without seed  or non viable seed

Eg : today’s banana, grapes watermelons orange  these are artificially induced  without fertiilization.

                               

On the basis of structure : as follows ;




Description:

1.   Simple fruits : they are resulted from syncarpous ovary or monocarpellary ones.

Further sub types :

a.   Dry fruits :

Pericarp not differentiated into three regions i.e. epicarp mesocarp and endocarp.

And pericarp  is dry.

             Three types of dry fruits :

·       Dehiscent or capsular fruit.

1.   Legume / pod :

Developed from superior monocarpellary gynoecium  that dehisces by both the halves  via suture . eg: members of fabaceae like  pea, gram, bean








2.   Follicle  : develops from superior  bicarpellary gynoecium but unilocular ovary  and dehiscence occur by  only one half . eg : Calotropis

3.   Siliqua : elongated, linear many seeded develops from superior bi carpellary unilocular ovary with parietal placentation  . This dehisces by both the halves from base to apex .

Eg : cruciferae family members

( silcula is just flat shortened siliqua eg : Iberis )

4.   Capsule : developed from multi carpellary syncarpous ovary

They can dehisce via :

1.   Pore  eg :  Papaver somniferum ,Argenome

2.   Locule  eg : cotton. Lady finger

3.   Septa eg  : linum

4.   Septa breaks to segments  eg :  Datura

·       In dehiscent or achenal fruit :

1.   Achene

Formed from monocarpellary pistil with superior unilocular ovary .

Membranous or ,leathery pericarp

Pericarp is free of seed coat except for one point .

2.   Caryopsis :

Developed from monocarpellary pistil with superior ovary

Here pericarp and testa are completely fused .

This type of fruit are iconic feature  of members of Gramineae family

 

3.   Cypsela

Developed from inferior  bicarpellary ovary  eg : Compositeae  family members .

4.   Samara  

Winged fruit from bi or tri carpellary .

Eg : shorea  (sal)

5.   Nut :

One seeded from superior syncarpous pistil with pericarp hard woody ir leathery .

Eg : Litchi, oak nut, cashew nut,  water chest nut

·       Schizocarpic or splitting fruits :

Many seeded dry simple fruit that breaks up to one seeded zone at maturity .

 

Types :

1.   Lomentum : a constricted pod.

2.   Cremocarp  : two seeded fruit at maturity splits into two mericarps . Eg : coriander , carrot


.

3.   Carcerulus  : fruit breaks up into  indehiscent  and single seeded 3 or more mericarps EG: malva

4.   Double samara: eg : Acer


5.   Regma  : dry three to many chambered fruit from syncarpous pistil  eg: castor , Euphorbia




                    


b.   Fleshy or succulent fruit :

Here, 3 region of pericarp found and these region becomes fleshy as name suggests.

 

Types :

a.   Drupe  :

 here endocarp is hard  socalled stone fruit  eg: Mango, coconut , plum .Almond

b.   Bacca or berry :

fleshy many seeded fruit with axile placentation .

Eg  : tomato,  guava ,grape, banana

c.    Pepo : fleshy mainly seeded developed from inferior syncarpous pistil.

Eg: cucurbits such as cucumber, pumpkin, watermelon.

d.   Pome : fleshy syncarpous fruit surrounded by thalamus while actual fruit lies within .eg: apple, pear

e.   Hesperdium: superior many celled  fleshy fruit  with axile placentation . endocarp project inward forming distinct chamber. Epicarp and mesocarp fuse together to for separable skin

Eg :  citrus like orange, lemon.

f.      Balausta : a false berry  where edible portion is juicy testa of seeds eg: pomegranate

 

2.   Aggregrate  fruits :

They develop from apocarpous pistil.

Types :

Aggregrate of simple fruits borne by single flower is termed as etaerio.

a.   Etaerio of follicles : Michelle, Vicna

b.   Etaerio of achenes : rose , lotus strawberry

c.    Etaerio of drupes : raspberry

d.   Etaerio of berries : custard apple

                           

3.   Multiple or composite  fruits :

a.   Sorosis : develops from spadix, catkin or spadix inflorescence . Eg : pineapple , mulberry , jackfruit.







b.   Syconus : developd from hypanthodium  eg : ficus ( banyan, fig, peepal )



                           

Functions of fruit :

1.   It helps in seed dispersal for continuity of life cycle.

2.   They  provide food and energy .

3.   In some, they even nourish seedlings.

4.   They are rich source of sugar, pectin, vitamins and organic acid .

 

 

           

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