What is a polymer? What type of chemical reaction builds polymers

The answer to your question is: Polysaccharide

The monomers of DNA are nucleic acids - the four in DNA are adenine, guanine, thymine, and cytosine - the A, C, G, and T of primary DNA structure.

Explanation:

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after receiving a stimus, the sensory receptors send(s) signals to the appropriate area of the body.  

the must be sensory neurons.  

hope its .

genetic variation can be caused by mutation (which can create entirely new alleles in a population), random mating, random fertilization, and recombination between homologous chromosomes during meiosis (which reshuffles alleles within an organism's offspring).