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 th...
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Dispersal by explosive mechanism-digieduco

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Dispersal by explosive and dehiscence mechanism of capsules of many plants are the means of dispersal of seeds to certain distance. The fruits of Impatiens balsamina (Balsaminaceae) and Oxalis Sp. (Oxalidaceae) when touched burst with sudden jerk and a little sound ; as a result the seeds are scattered to a distance. The ripe fruits (pods) of Abrus sp, Clitoria sp. etc. suddenly burst on twisting and thereby scatter the seeds.
Dispersal by explosive mechanism-digieduco

Dispersal by explosive mechanism-digieduco

Fruits of many members of Acanthaceae, e.g., species of Andrographis, Barleria, Ruellia, etc. dehisce suddenly into two valves from apex to base and thereby eject the seeds (attached to hook-like projections called jaculators or retinacula) to a distance. The long pods of Bauhinia vahlii (Caesalpinaceae) explode suddenly producing a great loud report and scatter the seeds. In Ecballium elaterium (cucurbitaceae),violent explosive ejection of seeds at the point of attachment of fruits with the stalk is noted when fruits get detached from the stalk.

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