Answer:
Attached R side groups
Explanation:
The proteins are one of the important biomolecules which are directly coded by the genetic material of an organism.
The proteins are composed of the amino acids which possess, an amine group, a carboxylic group and an attached side group called the R group.
It is the R group of an amino acid which determines whether the amino acid will a polar or a non-polar amino acid molecule thus it determines the properties of the amino acid in terms of chemical properties. The R side group are involved in the formation of bonds with the substrate of the environment and the tertiary structure of the proteins.
Thus, the presence of different R group is the key difference in 20 amino acids.
Answer: Sphincter muscles
Explanation:
The circular rings of smooth muscles, that can contract to regulate the movement of the smooth muscles that can contract to regulate the movement of food through the gastrointestinal tract are known as sphincter muscles.
These two layers are outer layer and inner layer. The outer layer is longitudinal and the inner layer is circular. They contract rhythmically to squeeze food.
Answer:
d.smooth muscle
Explanation:
Blood vessels contain only smooth muscle cells. These muscle cells reside within the tunica media along with elastic fibers and connective tissue
