<span>Protein tertiary structures
are known to be a three dimensional structure of a protein with a single
polypeptide chain (backbone) and one or more protein secondary structures known as
protein domains.</span>
Tertiary Structure Interactions
1) Hydrophobic Interactions: they are non-
covalent bonds and very important in the formation of tertiary structure.
2) Ionic Bonds: the interaction of both positive
and negative amino acids forms a bond that helps to stabilize the protein molecules.
3) Hydrogen Bonds: this bond exit between the
amino acid with hydrophilic side chain found on the surface of the molecules and
water molecules in a solution.
4) Disulfide Bridges: it is a strong covalent bond commonly found between cysteine residues in close proximity space.
Answer:
<em><u>This is the only phylum of the animal subkingdom Parazoa and represents the least evolutionarily advanced group of the animal kingdom. ... Sponges are the only animals that lack tissues with mass of cell embedded in gelatinous matrix.</u></em>
<span>The spicules have an important purpose for loosely constructed animal such as sponge. First of all, spicules give structure which is vital due to loose construction. Secondly, it protects from predators. This is similar to porcupine quills in serving to protect.</span>
Darwin explained that evolution occur due to natural selection.