The pairing of in dna is the key feature that allows dna to be copied.

a.) nucleotides
b.) nitrogen bases
c.) chromosomes
d.) codons

1. they vary with a higher number because boiling is way hotter than melting

smooth muscle is composed of involuntary muscles found within the walls of organs and structures such as the esophagus, stomach, intestines, and blood vessels. those muscles push materials like food or blood through organs. unlike skeletal muscle, smooth muscle can never be under your control.