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Human Health and Disease — BIOLOGY STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceBIOLOGYHuman Health and Disease5 Marks
Question
(i) Define contact inhibition.
(ii) Explain the difference between benign tumors
and malignant tumors.
(iii) Write any one cause of cancer.
✓

Answer

(i) Contact inhibition : 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.
(ii) Difference between benign tumors and malignant tumors :
S.No.Benign TumorsMalignant Tumors
1It is a non-cancerous tumor.Whereas it is a cancerous tumor.
2They normal remain confined to their original location.Whereas it is not confined to its original location.
3Metastasis property is not found.Metastasis property is found in these.
4Cause little damage to body.Cause more damage to body.
(iii) Cause of cancer : The chemical carcinogens present in tobacco smoke have been idetified as a major cause of lung cancer.

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