![]() (i) Cistern or lamellae (Fluid filled lumen) Golgi apparatus occure in three morphological forms Golgi complex show a membranous structure of the cell Golgi complex was described by Camillo Goligi in 1898 in the nerve cell of born owl. (ii) Smooth endoplasmic reticulum (without ribosomes) for secreting lipidsĮR occur in three morphological forms viz, cisternal vesicles and tubular.ĮR is serve as channel for the transport of material (specially proteins) between various regions of the cytoplasm between the cytoplasm and the nucleus. (i) Rough endoplasmic reticulum (RER) with ribosome’s attached on its surface for synthesizing proteins It is a membranous network, enclosing a fluid filled lumen. These are-Įndoplasmic reticulum (ER) or Ergastoplasm The activities of the cell are performed by different cell organelles. The portion of the Protoplasm with out nucleus is called cytoplasm.Ĭytoplasm is clear, colorless, jelly-like, Viscose semisolid substanceĬytoplasm is the center for most of the metabolic activities of the cell and for this purpose it has a number of specialized structural called cytoplasmic organelles in it. A cell may be have one nucleus (uninucleated) as in many plants and animals, two nuclei (binucleate) as in a protozoan -e.g., paramecium, a many nucleic multinucleate as in certain fungi. RNA is helpful in protein Cytoplasm in the cytoplasm. (ii) Nucleolus, Containing RNA (Ribonucleic acid). ![]() At the time of division chromatine material condenses into rod like bodies called Chromosomes. (i) Chromatin material which is in the form of an intertwined mass of thread –like structures, the chromatin material, mainly consisting of DNA (Deoxyribonucleic acid) is responsible for storing and transmitting the heredity information from one generation to another. The chief components of the nucleus are as undermention. The nuclear membrane has some pores, which allow the transfer of material between nucleoplasm present inside nucleus and the cytoplasm. Nucleus enclosed by a double-layered membrane, called nuclear membrane, which separates it from the cytoplasm. Nucleus is prominent, spherical or oval structure, located near the center of the cell and it is the controlling center of all the cell activities. Plant cell loses water through the process of Osmosis due to which there is Shrink age or contraction of the of the cell away from the cell wall, this phenomena is known as plasmolysis. Plant cell wall is mainly composed of celluloseĬellulose is a complex substance and provides structural strength to plants. Plant cell in addition to the plasma membrane have another rigid outer covering called cell wall. ![]() Hence the cell membrane is called a selective permeable membrane. The plasma membrane allows or permits the entry and exit of same material in and out of the cell. Plasma membrane is made up of lipids and protein and provides a mechanical barrier for the protection of the inner cell content. Plasma membrane is the outermost covering of the cell that separate the contents of the cell from the surrounding medium. Purkinje coined the term ‘Protoplasm’ for the fluid substance of the cell in 1839. Robert Brown discovered the Nucleus in cell in 1831. He observed the cells in a cork slice of plant with the help of Primitive microscope. It is an aggregate of molecules of various chemicals mostly organic molecules like proteins, Carbohydrates fats, nucleic acid etc.Ĭell were first discovered by Robert Hooke in 1665. In man, the number of cells is estimated to be about 100 trillion (1014).Ĭell is made of life giving substance called protoplasm. Many cells group together in a single body and perform different functions are called Multi cellular organism like fungi plants and animals.Ĭells vary in number, shape and size. A single cell may constitute a whole organisms as in Amoeba, Chlamydomnas, Paramecium and bacteria these organisms are called unicellular organisms.
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