What is meant by contact inhibition ?

Options

A. Contact with other cells promote their uncontrolled growth .
B. Contact with other cells doesn’t inhibits their uncontrolled growth.
C. Contact with other cells inhibits their programmed cell death.
D. Contact with other cells inhibits their uncontrolled growth

Answer

**Step-by-Step Solution:**

1. **Definition of Contact Inhibition**: Contact inhibition is a regulatory mechanism that functions to prevent cells from dividing when they come into contact with each other. This process is crucial for maintaining proper tissue architecture and function.

2. **Mechanism of Action**: When cells are in a crowded environment and touch each other, they receive signals that inhibit further cell division. This is important for normal growth and development, as it helps to prevent excessive cell proliferation.

3. **Role in Cancer**: In normal cells, contact inhibition is a key factor in controlling growth. However, cancer cells often lose this ability, leading to uncontrolled growth and tumor formation. This loss of contact inhibition is one of the hallmarks of cancer.

4. **Importance in Tissue Repair**: Contact inhibition also plays a role in wound healing. When cells migrate to a wound site, they initially proliferate to close the wound, but once the cells meet at the edges, contact inhibition kicks in to stop further division.

5. **Conclusion**: In summary, contact inhibition is a vital process that regulates cell growth and maintains tissue integrity by preventing over-proliferation of cells when they come into contact with one another.

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