Cell membrane function and difference-digieduco

on
  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...
0

Dictyosomes-digieduco

on
Dictyosomes (Golgi apparatus in animal cells)- Golgi body-like cytoplasmic inclusion i.e Golgi apparatus have been reported in plant cells with the help of electron microscope, e.g. root tip cells of Allium sp., trichoblast of hydrocharis morsusranae ( cutter 1978), root cells of Pisum sativum, (Wilson and Morrison, 1967) etc.
Dictyosomes-digieduco

The number of Golgi apparatus in each cell may vary from one to many. Golgi apparatus of plant cells consists of a system of dictyosomes occurring throughout the cytoplasm (Cutter, 1978). A dictyosome consists of a small stack (from 2-20) of smooth double membrane-bound flattened sacs (cistemae) of varying size, which are often dilated at ends ; these are arranged in parallel rows, and are associated at the margins with a number of spherical, larger and smaller vesicles (microvesicles).

Functions-The dictyosomes are now known to function in the secretion of sugar (in nectar secretion), polysaccharides (cell wall materials), and polysaccharide protein complexes (Fahn, 1982) ; the function of dictyosomes in the synthesis and transport of polysaccharides has also been demonstrated experimentally by combining autoradiography with electron microscopy (Cutter, 1978). Dictyosomes are also related to wall formation Mollenhauer et al, 1961 ). 

Comments

Post a Comment