THE CELL
CELL COMMUNICATION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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a growth factor and a mitotic factor
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ATP synthetase and a protease
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cyclin and tubulin
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cyclin and a cyclin-dependent kinase
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Detailed explanation-1: -As their name suggests, CDKs require the presence of cyclins to become active. Cyclins are a family of proteins that have no enzymatic activity of their own but activate CDKs by binding to them.
Detailed explanation-2: -What substances form the cyclin-cyclin dependent kinase combinations that control the stages in the cell cycle? A. fats and proteins.
Detailed explanation-3: -Maturation-promoting factor (MPF) MPF provides a good example of how cyclins and Cdks can work together to drive a cell cycle transition. Like a typical cyclin, M cyclin stays at low levels for much of the cell cycle, but builds up as the cell approaches the G 2start subscript, 2, end subscript/M transition.
Detailed explanation-4: -Maturation-promoting factor (MPF) is a cell cycle control element able to cause cells to enter M-phase upon microinjection and will induce metaphase in nuclei incubated in cell extracts. Previous work has shown that MPF is composed of a complex between p34cdc 2 protein kinase and a B-type cyclin.