Answer:
When both _signal molecules_ are in their receptor sites, the molecules form a dimer (two molecules joined together). ATP is converted to ADP and the _phosphate group_ gets attached to the tyrosine molecules. The addition of the _ relay proteins_ causes a cascade of cellular responses.
Explanation:
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A)Demographic; because the census studies things such as births,death, and even disease which show changes in human population
Gene mutations provide new traits, those that are useful evolve and strive into new species'. Those that are not so useful, eventually die off
Computer modeling is used in biological studies because it can be used to make models that can be used to hold data.