Answer:
B. only the animals living in water
Enzymes are protein macromolecules.
Rainwater picks up carbon dioxide from the air and as it percolates through the soil, which turns into a weak acid. This slowly dissolves out the limestone along the joints, bedding planes and fractures, some of which become enlarged enough to form caves.
The answer is A
RNA is always single strand
All amino acids are structurally the same, in that they contain a central carbon atom, an amine group, a lone hydrogen at. Our DNA is contained in our chromosomes. The thing that is different about each of the 20 amino acids is the make-up of the R group