Define these 3 terms:
isotonic
hypertonic
hypotonic

Isotonic

denoting or relating to a solution having the same osmotic pressure as some other solution, especially one in a cell or a body fluid.

Hypertonic

having a higher osmotic pressure than a particular fluid, typically a body fluid or intracellular fluid

Hypotonic

having a lower osmotic pressure than a particular fluid, typically a body fluid or intracellular fluid.

Explanation:

answer; ///(b) it is composed of four protein chains and four heme groups;

i think it is dna, i'm not totally sure but i think it might be.