The right answer is D (less responsive to antigens)
It is proven that, after puberty, thymus activity (an organ that is included in the lymphatic system, producing T cells that pick up antigens) decreases and that in adult and aged people the thymus has no role. Work done in humans indicate that in fact the cellularity begins to decline from birth in favor of lymphocyte perivascular spaces and connective and adipose tissue, which leads to a decrease in the capture of antigens.
Answer:
Option (B).
Explanation:
Heart is the main pumping organ of the body. The human heart is divided into four chambers that are right atria, right ventricles, left atria and left ventricles.
The left and right ventricles can easily be distinguished on the basis of their thickness. The right ventricle is less thicker than left ventricle. The thickness of right ventricle is 9mm whereas the thickness of left ventricle is around 40mm.
Thus, the correct answer is option (B).
The answer is hydrogen and oxygen
using subtraction to determine the volume dispensed
making sure that you read the volume with the liquid inside the pipette at eye level
ensuring that air bubbles are not in the column of liquid inside the pipette