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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Dehiscent fruits or dry fruit-digieduco

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Dehiscent fruits or dry fruit are always dry, the pericarp breaks down, is. bursts on ripening and the seeds are liberated. There are different types as follows :
Dehiscent fruits or dry fruit-digieduco

1. Follicle-It is a dry many-seeded dehiscent fruit which develops from superior monocarpellary ovary. The pericarp dehisces along the ventral suture only..Examples-fruit of Calotropis procera, C. gigantea (Asclepiadaceae), Alstonia scholaris (Apocynaceae), etc.

2. Legume or Pod- lt is a dry many-seeded dehiscent fruit Which develops from a superior monocarpellary ovary ; here the pericarp dehisces along both ventral and dorsal sutures. Examples--fruits of the family Leguminosae e.g. Pisum sativum, Dolichos lablab, species of Crotalaria, Lathyrus, Lens, Cicer, Phaseolus, etc.
Dehiscent fruits or dry fruit-digieduco

3. Capsule-It is an one or more-celled dry dehiscent, many-seeded fruit which develops from a superior or inferior polycarpellary ovary ; the dehiscence may take place either by valves or pores. The mode of dehiscence may be along the septas 0f the component carpel (septicidal) or dorsal sutures of the respective carpels (loculicidal) or by both when the seeds are left on the central column after falling of the valves (septifragal). Examples of septicidal capsules are Rhododendron sp., some fruits of the family Liliaceae; examp1es of loculicidal capsule are species of Hibiscus, Gossypium etc ;example of septifragal capsule is Datura sp.

4. Siliqua-The fruits of the family Cruciferae are usually siliquas. This dry dehiscent fruit develops from a superior bicarpellary ovary which is one-chambered, but becomes two chambered by the formation of a false partition wall called replum. It dehisces from base to apex ; the seeds are left on the false partition wall i.e. the replum.

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