Cell membrane function and difference-digieduco

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  Functions of cell membrane : (a) The proteins and enzymes present in the cell membrane helps in the transport of certain substances like sugar, sodium and other ions etc. across the cell membrane. (b) Cell membrane protects the internal structures of the cell and different organelles of the cytoplasm. (c) It maintains the shape of the cell. (d) It acts as a selective permeable membrane because it allows to pass certain substances while others are not, hence it helps in the transport of selective materials from and to the cells. (e) The membranes on the cytoplasmic organelles and nucleus most probably formed from the plasma membrane. (f) Other important functions of cell membrane of the cells are endocytosis and exocytosis . Endocytosis is the process by which materials are transported into the cells by the formation of vesicles. It includes two processes-phagocytosis (cell eating) and pinocytosis (cell drinking). The reverse process of endocytosis is exocytosis. During this p
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Schizocarpic or Splitting fruits-digieduco

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The term Schizocarpic or Splitting fruits is applied to the fruits which break up into a number of indehiscent bits, generally equal to the number of component carpels. Each indehiscent bit, called mericarp, contains one or more seeds.

Here the pericarp does not burst or break down but seeds are liberated only by the decomposition of the pericarp or by its Splitting.

There are usually five types of schizocarpic fruits as follows :
Schizocarpic or Splitting fruits-digieduco

1. Cremocarp-It is a dry and two seeded fruit which develops from the inferior bicarpellary ovary. The two halves i.e. two mericarps of this fruit are attached on a common axis-the carpophore ; on maturity they separate but remain attached
pendulously by a slender chord. .Examples-Coriandrum sativum, Foeniculum vulgare and many other species belonging to the family Umbelliferae.

2. Samara-It is a dry, two or more celled and winged fruit which develops from a superior bi-or tricarpellary ovary. The wings are formed from the pericarp. The fruit breaks up into component parts and each part contains a seed but does not split further to liberate the seed. Examples-Hiptage madhablata (Malpighiaceae), Dioscorea sp. (Dioscoreaceae) etc. Fruits of Shorea robusta (Dipterocarpaceae) and some other species are also winged but the wings are not formed from the pericarp, rather wings-are the persistent sepals of the calyx whorl-such a fruit is called samaroid.
Schizocarpic or Splitting fruits-digieduco

3. Regma-This is a dry fruit which develops from a superior trior polycarpellary ovary. The fruit splits up into as many parts, called cocci, as there are carpels. Each part contains one or two seeds which are liberated on the decaying of the dry pericarp. Examples-Ricinus communis (Euphorbiaceae), Hura crepitans, Geranium sp. (Geraniaceae) etc.

4. Lomentum-This is a .dry legume like fruit developing from a superior monocarpellary ovary. Here the fruit is transversely constricted between the seeds and on maturity the fruit breaks up into bits containing one or more seeds. Examples-species of Acacia, Mimosa, Entada gigas (Mimosae) etc.

5. Carcerule-This is small, dry fruit which develops from a superior bicarpellary ovary. The fruit later on splits into four chambers enclosin g one seed in each. Carcerule is the characteristic fruit of the members of the family Labiatae.

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