The skeletal system since the brain is apart of the skeletal system.
10. before replication begins, the strands of DNA are separated and used as templates for the new strands. the replication process creates 2 identical double helixes, each has 1 new strand and 1 old one.
11. without dna replication, damaged cells could not be replaced/repaired and cells need dna, cells would become mutated without dna replication.
12. mutations are rare because dna polymerase proofreads the strands but if the process occurred incorrectly and was not corrected by the polymerase, the cell would become mutated and could be really harmful.
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Answer:
Ligand-receptor interaction is the first interaction that triggers cell signalling.
Ligands are the hormones, drugs or neurotransmitters that specifically bind with receptors present in cell surface to initiate cell signalling. Ligand binding to the receptor is reversible. Binding of the ligand to the receptor can activate or inactivate receptor. Activation may lead to cell signalling pathways. Inside cells, there are secondary molecules which on activation starts a cascade of reactions. which in-turn regulate the function of the ligand molecule.
At first, the activated receptor relates with G proteins molecules in the cell.
before the ultimate physiological effect of the ligand on the cell's behavior is produced Therefore, the cellular signaling starts as soon as the first messenger (the ligand) binds to its receptor.
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Scholarship..............
the imbetween climates, its not cold its not warm, it subartic, or sub saharran, hope this helps