Identify the correct facts about cancer.
(A) Cancer cells continue to divide and build up a mass of cells called a tumour.
(B) Cancer cells appear to have lost the property of contact inhibition.
(C) Malignant tumours remain confined to their original location and do not spread to other parts of the body.
(D) In benign tumours, the cells grow very fast, attack the surrounding normal tissues and damage them.
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → (A) and (B) only
Normal cells stop dividing when they touch other cells. This is called contact inhibition. Cancer cells have lost it. They keep dividing and form masses of cells called tumours. Tumours are of two types. Benign tumours stay in their original place and do little damage. Malignant tumours grow fast, invade the tissue around them and spread to other parts of the body (metastasis).
(A) Cancer cells continue to divide and build up a mass of cells called a tumour. — Correct. Unchecked division builds up a tumour.
(B) Cancer cells appear to have lost the property of contact inhibition. — Correct. This is why they do not stop dividing.
(C) Malignant tumours remain confined to their original location and do not spread to other parts of the body. — Incorrect. This describes benign tumours. Malignant tumours spread through the blood to far-off sites and start new tumours there.
(D) In benign tumours, the cells grow very fast, attack the surrounding normal tissues and damage them. — Incorrect. This describes malignant tumours. The features of the two tumour types are reversed in statements C and D.
NCERT Extract:
Cancer – …
