Question

The modern cell theory is called
(A) Protoplasmic Theory.
(B) Cell Principle.
(C) Cell Doctrine.
(D) Both B and C.

Answer 1

Hint: Cell is the basic structural and functional unit of life or the body of living organisms. The cell is also known as a building block. Groups of cells combine to the form tissue. On the basis of numbers of cells, organisms can be categorized into two groups unicellular and multicellular. Unicellular are single celled and multicellular comprises many cells.

Complete Answer:
Modern cell theory is called cell principle or cell doctrine. The modern cell theory was formulated by Matthias. Schleiden and Theodor Schwann in 1839.
The postulates of modern cell theory are
(1) All living things are composed of cells.
(2) Cell is the basic structural and functional unit of living things.
(3) All cells arise from pre-existing cells. It also states that organisms grow by addition of cells and not by increase in the size of cells.
(4) These cells contain hereditary information which is passed onto the next generation during cell division.
(5) All cells are relatively the same in chemical composition and metabolic activities.

Cell theory was proposed by Schleiden and Schwann that gave three postulates. Modern cell theory adds more postulates to cell theory. The term protoplasm was given by Purkinje while observing the sap of plant cells. The similarities between protoplasm and sarcode lead to the development of protoplasmic theory which states that protoplasm is the physical basis of life.

Therefore, from above explanation correct option is (D) Both B and C.

Note: Cell doctrine or cell theory states that all organisms have the same kind of organization and cell principles state that the cell forms the basis structural and functional unit of life. Both the postulates are included in modern cell theory.