4. chargaff's research had shown that there are four monomers in dna, in which two are always present in equal
amounts and the other two are always in equal amounts. we know that these monomers are the
of dna.

Amino acids contain the elements carbon, hydrogen, oxygen, nitrogen, and sometimes sulfur. of the 20 amino acids found in humans, 11 are called "nonessential" because they can be manufactured by the body when needed. which elements in these 11 amino acids are commonly obtained from the metabolism of sugar molecules?

What happens as electrons move along the chain of molecules known as the electron transport chain? they gain energy, which causes atp molecules to lose phosphate groups. they gain energy, which causes h *ions to join with oxygen to produce water. they lose energy, which is then used by the cell to make atp. they lose energy, which is then used to break down atp.

Why are current extinctions of concern to enviromentalists?