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
Define the Nutritional assessment methods? Nutritional assessment methods commonly used are enumerated herewith. 1. Bodyweight measurement s remain to be the most practical

Categories of Secondary Inductions The secondary inductions are categorized into two types. 1) Instructive Interaction : In such type of an interaction the inducing tissue

Pericardiocentesis It is removal of fluid form the pericardial sac. It is a specialized procedure done n ICU or cardiac cath lab or OT. A 16 or 18 gauge needle is inserted

Q. Explain Spoilage of Sweetened condensed milk? The sweetened condensed milk contains about 8% milk fat, 23% total milk solids and sweetened with the addition of a sweetener,

BIRT H CONTROL - Birth control methods which deliberately prevent fertilization are contraception. These methods may be temporary or permanent. 1 .       TEMPORARY MET

How different are the endosperm of gymnosperms and the endosperm of angiosperms? In gymnosperms the endosperm is haploid (n), it is known as primary endosperm. In angiosperm th

Define Sterol Regulatory Element Binding Proteins (SREBPS)? These belong to a general family of transcription factors. They are synthesized as membrane embedded proteins in res

Failure to organize proper adjusting entries causes net income and the balance sheet to be in error. Using Micro Train Company as an instance this section has discussed and illustr

F ALLOPIAN TUBE - Fertilisation occur in it. 10-12 cm long muscular tube. It is supported by double fold of peritonium. It shows 4 regions - (i ) Infundibulum - Bro

Explain acid and bases? Acids and Bases :  Some aqueous solutions, however, such as HCl, form an excess of hydrogen ions [ H + ] and are called acids. Others, such as NaOH,