How does high surface tension of water affect living organisms such as a water stride?

What do all macromolecules have in common with each other? oa. they all are formed from the same elements. ob. they all have major roles in cell membranesoc. they all act as catalysts in the body. od. they all have peptide bonds between carbon atoms.

Which way do the nitrogenous bases in dna pair up? a. a and g; t and c b. a and c; t and g c. a and t; g and c d. a and a; t and t; g and g; c and c

What are the doorways into and out of cells, attached to the membrane, and built in the rough er.