Answer is
body-brain barrier.
Explanation:
Mannitol injection is used to reduce swelling ande pressure around the brain.
It enhances flow of water from tissues including cerebrospinal fluid and the brain into plasma and interstitial fluid.
Upwelling is a process in which cold water from depths arise to the surface
The building blocks of protein are C. AMINO ACIDS.
Amino acids are made up of a center carbon atom bound positively to a charged amino group and a negatively charged carboxyl group and a side chain.
The primary structure of a protein is the sequence of an amino acids that are attached together by a peptide bond
The secondary structure of a protein, the polypeptide is folded through the mechanisms of amino acids rotating around bonds folding into a helix or a pleated sheet structure and stabilized by a hydrogen bond.