Cell theory, Biology

Cell Theory

The term cell was first used by an English cytologist, Robert Hooke (1665) not for unit protoplasmic masses, but for the well defined and empty compartments, he observed in a thin slice of cork under his self invented   microscope. This finding of Hooke was cork is a dead and dry plant material. Obviously, what Hooke actually   observed were empty cells with cellulose walls originally produced by the living cells they surrounded, yet the term cell has since been retained and universally adopted for unit protoplasmic masses of live organisms.

Leeuwenhoek (1674-76) discovered free living cells. He also observed the presence of a distinct central structure in certain unicellular organisms and some cells of multicellular organisms.  Robert brown (1831) discovered that a central structure is an essential is an essential part of all living cells. He named it as nucleus first observed the jelly like protoplasm in living   cells and termed it arcade. When observation upon varied types of cells and unicellular organisms many scientists during17th and 18th centuries were leading to the realization that plants and animals were made up of component cells. Two German biology Matthias j Schleiden and Theodor Schwann (1938-39) separately formulated. Famous cell theory stating that cells are the basic structural and functional unit or building blocks of the bodies of all organisms, like the bricks of house. Thus this cell theory came as the most fundamental biological generalization implying a common pattern of body architecture in all living beings. 

Posted Date: 9/26/2012 7:01:33 AM | Location : United States







Related Discussions:- Cell theory, Assignment Help, Ask Question on Cell theory, Get Answer, Expert's Help, Cell theory Discussions

Write discussion on Cell theory
Your posts are moderated
Related Questions
1. The level of organization intermediate between unicellular and the multicellular - organisms are composed of multiple cells but these fail to exhibit specialization of those cel

Q. What kind of exoskeleton do some molluscs present? Some molluscs, like gastropods and bivalves secrete an external calcareous carapace (the shell). Calcium carbonate is a fo

Define Nutritional Support Management for pancreatic cancer? When there is deficiency of exocrine pancreatic secretions, adequate amounts of pancreatic extract are helpful. It

Q. Preservation of species diversity? Genetic diversity is, thus, important for the preservation of species diversity, and hence biological diversity. A knowledge of the variab

Explain how you would create a standard curve to determine the amount of orange dye that had been added to a can of orange soda

Dracunculiasis (guineaworm infestation) Dracunculiasis, a disease of man, which has been known since antiquity, is caused by the nematode parasite Dracunculus medinesis. The p

Q. What are the main symptoms of the pulmonary and of the intestinal phases of the ascaris infestation? In the pulmonary period the ascaris infestation causes hemoptysis, cough

Describe the Classification of Arthropoda? Most arthropods also go through a growth process called metamorphosis, whereby they change their bodies into an entirely different fo

Which photosystem-I or II-most likely evolved first? Describe your reasoning. Photosystem II most likely evolved first, because it changes electrons lost from chlorophyll

In the eukaryotes, the transmit RNA genes exist as multiple copies and are transcribed by RNA polymerase III or RNA Pol III. As in prokaryotes, various tRNAs may be transcribed tog