Question

according to the theory how new cells were formed​

Answer 1

✔According to cell theory, new cells are formed from pre-existing cells. ✔Rudolf Virchow in 1855 first explained that cells divide and new cells are formed from pre-existing cells.

Answer 2

R .Virchow (1885 ) elaborated the above theory and said that are living cells originate from pre - existing cells ( Latin phrase -" Omnis cellula e cellula " i.e,, new cells arise from pre -existing one) according to him cell division is only the central phenomenal in the life cycle of first cell this fact is known as " Law of cell lineage".

This fact has been included in the cell theory. hence the modified form of cell theory is known by name " Modern Cell Theory " or 'Cell doctrine ' or 'Cell principal'

According to this theory -:

• All leaving organisms are made of cell and their products and cell is the structural and functional unit of the organism.
• New cell arise from pre existing cell by cell division.
• Genetic information is inherited in DNA molecule and it is carried to next generation through reproduction.
• All cells of multicellular organism are fundamentally similar but may differ in their physicology.
• Cell is the basis and smallest unit of life.

Exception-:

1. Viruses lacks cellular organisation and protoplas which is essential part of the cell is also absent in them hence viruses are the actual exception to the theory.
2. Acellular organism example protozoans are the expression to self theory because their body is not different into cell
3. Organism example bacteria lacteenucleus has they cannot be explained with the help of this theory.
4. Some organism like Mucor,Vaucheria, Rhzpous also exceptions to cell theory because they contain more than one nucle in cell.

Significance -:

• According to this theory new cell organet from existing cell has transmission of genetic character has been going on formed generation to generations is life begin.
• According to this theory the base of activities related to various disease is cell where by this theories prove to be correct.
• Kollikar related cell theory to embryology and said that the organ of organism is due to fusion of two reproductive cell.
• By the study of various cell, it is clear that structure and chemical organisation of cell are almost fundamentally similar.