The correct answers are:
2) Peptide bonds form from nucleophilic attack by an electron pair on an alpha - amino nitrogen atom on an alpha - carboxyl carbon atom of another amino acid and
4) Peptides are polymers of amino acids.
A peptide bond is an amide type of covalent chemical bond. It is formed between two amino acids: C1 (carbon end) of one alpha-amino acid and N2 (nitrogen end) of another. Peptide bonds are the basis for the formation of a peptide chain and consequently protein. Formation of peptide bond is a condensation process, meaning that when two amino acids combine and link, water molecule is released and dipeptide is a product of that reaction.
Answer: FROM THE PULMONARY VEIN
Explanation: oxygen poor blood from the right ventricle into the lungs, where the oxygen enters the bloodstream. The pulmonary veins bring oxygen rich blood to the left atrium.
D is the answer to the question
Answer:
The presence of a few PLATES
