Non-Infectious diseases and its types/cancer

NON-INFECTIOUS DISEASES :

- These diseases cannot be transmitted from one person to another and not caused by pathogens. 

CANCER:

- it can be defined as an uncontrolled abnormal 

growth or proliferation of cells without any differentiation.

(1) in our body, cell growth and differentiation is highly controlled and regulated.

(2)the cancer cells divide repeatedly with 

And controlled cell divisions. They do not require 

extracellular growth factors. New cancer cells are known as NEOPLASTIC CELLS. 

(3) cancer cells have lost the property of contact 

inhibition shown by normal cells in which contact

With other cells inhibit their uncontrolled growth.

The repeated division of cancerous cells, form a large mass of cells called tumours.

(4) cancer cells move from tumour to new sites 

through blood and form secondary tumour. 

This invasion of cancer cells from one part to other parts by the body fluids is called Metastasis.

(5) Tumours  are of  two types

*BENIGN TUMOUR : it is non-cancerous

-it does not show metastasis. 

-growth stops after reaching a certain size. 

-less fatal. 

*MALIGNANT TUMOUR: it is cancerous 

-it shows metastasis. 

- growth occurs indefinitely. 

-highly fatal.