The correct answer is:
D
.Villi in the small intestine have thin-walled capillaries to make the absorption of nutrients more efficient.
Explanation:
The small intestines are well adjusted for absorbing nutrients during digestion by being very long, having villi and microvilli that enlarge surface area, using muscular contractions to move and mix food, and raising and housing digestive enzymes and bile that aid the breakdown of food. The inner surface of the small intestine is not flat but thrown into circular folds, which not only enhance surface area but aid in preparing the ingesta by acting as baffles. Villi: the mucosa makes multitudes of ridges which project into the lumen and are satisfied with epithelial cells.
Enzymes lower activation energy through various means, including positioning substrates together in the proper orientation, applying torque on the substrates, providing the proper charge or pH microenvironment, and adding or removing functional groups on the substrates.
Answer:
Cellulose
Explanation:
Cell walls made of cellulose are only found around plant cells and a few other organisms. Cellulose is a specialized sugar that is classified as a structural carbohydrate and not used for energy. ... While cell walls protect the cells, they also allow plants to grow to great heights. You have a skeleton to hold you up.
Answer:
b. They are produced by memory B cells
Explanation:
The rapid cell division in activated B cells is followed by the differentiation of daughter cells into the plasma cells. The plasma cells are the precursor for antibodies and memory B cells. The antibodies kill the antigens while memory B cells are long-lived cells.
Hence, antibodies are not produced by memory B cells but by plasma cells.
