DNA in a cell replicates.

What is this an example of?

i'd say that the moon rock is about 2.2 billion years old.

bradykinin is a physiologically and pharmacologically active peptide of the kinin group of proteins, consisting of nine amino acids.

while the heads of the phospholipid structure attract water, the tails are hydrophobic. the model shows how the hydrophilic section folds around the fluid molecules to bring them into the cell so they don’t need to pass through the hydrophobic tails.  

the answer is b.

hope it