Answer:
Option 4 - Calcium
Explanation:
The <em>divalent cation </em>called <em>calcium</em> is needed to provide additional support to the bone matrix.
Calcium is considered one of the most <em>important components</em> in bone development. It helps in the formation as well as maintenance of bone. During the modeling and remodeling process of bones, calcium facilitates the formation of <em>semi-hard new tissues</em> which leads to the formation of new bone which is very hard.
Due to this reason, calcium is needed to create extra bone matrix support.
The ileum contains villi that project into the lumen and increase the amount of surface area.
Villi are small finger-like structures that project into the lumen of the small intestine. Villi increase the surface area of the intestinal walls for easy and quick absorption of digested food with the addition of digestive secretions. Villi vary in length from about 0.5 to 1 mm. They are usually found in large numbers at the beginning of the small intestine and they reduce toward the end of the tract.
Answer:
-20 kcal/mol (It stays the same)
Explanation:
Enzymes will reduce the Gibbs free energy of activation, but will neither increase or decrease the free energy of reaction.
Enzymes means of activity is by decreasing the activation energy (Ea or ΔG✳) for a reaction. This in turn raises the reaction rate.
Free energy of reaction
= free energy of product - free energy of substrate
The free energy of the product remains constant even without the enzyme. Hence, the enzyme would show no effect on the free energy of the reaction.
The attached image shows the effect of changes in enzyme concentration on the free energy.