Contact inhibition is a property of:
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → Normal cells
Contact inhibition means that when a cell touches other cells, it stops dividing. This keeps cell growth in check. In cancer this control breaks down.
Option (1) Normal cells — Correct. Normal cells show contact inhibition: contact with other cells stops their uncontrolled growth. Cancer cells have lost this property, so they keep dividing and form tumours.
Option (2) Cancer cells — Incorrect. Cancer cells have lost contact inhibition, so they keep dividing and form tumours.
Option (3) B-cells — Incorrect. B-cells are lymphocytes that make antibodies; contact inhibition is not named as their property.
Option (4) T-cells — Incorrect. T-cells are lymphocytes of cell-mediated immunity; the term is not used for them.
NCERT Extract:
Cancer – “… In our body, cell growth and differentiation is highly controlled and regulated. In cancer cells, there is breakdown of these regulatory mechanisms. Normal cells show a property called contact inhibition by virtue of which contact with other cells inhibits their uncontrolled growth. Cancer cells appears to have lost this property.”