Which of the following mechanisms is not directly involved in inactivating an activated RTK?
(a) dephosphorylation by serine/threonine phosphatases
(b) dephosphorylation by protein tyrosine phosphatases
(c) removal of the RTK from the plasma membrane by endocytosis
(d) digestion of the RTK in lysosomes
(a) RTKs are phosphorylated on tyrosines by their dimerization partner, which is also a tyrosine kinase, and thus the reversal of these phosphorylations involves protein tyrosine phosphatases, and not protein serine/threonine phosphatases. Endocytosis of the receptor and its ultimate digestion in the lysosome are other methods that the cell uses to down-regulate active receptors.
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Imagine you were there when Stanley Miller carried out his experiment about the building blocks of life. If Miller originally identified five different amino acids, how many polypeptides that are 10 amino acids long
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If each of two bacteria have a %GC of 50%, this means that they are both definitely closely related
Indicate whether this statement is true or false.
If mRNA is not modified what will result? a. The mRNA will not be able to leave the nucleus
b. The cell will self destruct. c. Mutation. d. The new protein will become activated earlier. e. The DNA code will become altered.
When mangroves and seagrasses are reduced or damaged all occur except:
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