OBJECTIVE LIFE SCIENCE
CELL BIOLOGY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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normal cells and cancer cells both grow slowly
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cancer cells grow at a faster rate than normal cells
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normal cells grow at a faster rate than cancer cells
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cancer cells and normal cells both grow rapidly
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Detailed explanation-1: -For instance, cancer cells: grow in the absence of signals telling them to grow. Normal cells only grow when they receive such signals. ignore signals that normally tell cells to stop dividing or to die (a process known as programmed cell death, or apoptosis).
Detailed explanation-2: -Like healthy cells, cancer cells can’t live without oxygen and nutrients. So they send out signals called angiogenic factors. These encourage new blood vessels to grow into the tumour. This is called angiogenesis.
Detailed explanation-3: -Normal cells or non-malignant cells show contact inhibition i.e normal cells stop growing when they come in contact with nearby cells. However, cancer cells do not stop their proliferation under such conditions and continue their growth.