Answer:
when G1/S cyclin-CDK is activated. Expression of G1/S cyclins is regulated by E2F proteins
Explanation:
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Commitment to cell division occurs at Start when G1/S cyclin-CDK is activated. Expression of G1/S cyclins is regulated by E2F proteins in conjunction with pRB proteins.. Mitogens stimulated cell division by increasing the amount of G1 cyclins.
Answer:
Inside the air sacs, oxygen moves across paper-thin walls to tiny blood vessels called capillaries and into your blood. A protein called haemoglobin in the red blood cells then carries the oxygen around your body.
Explanation:
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