Exhaled air has a higher concentration of CO2 and the lungs are humidified within
The best way is to compare the DNA of the two species. The more nitrogenous bases and amino acids two species have in common, the more closely related they are.
I believe you're talking about a population.
Andrea became highly aroused and alert when she was stung by a bee thanks to the activation of her reticular formation. Recticular formation is a nerve network of nuclei clusters found in the human brain stem. It has projection to the thalamus and cerebral cortex that allow it to exert some control over which sensory signals reach the cerebrum and the conscious of the body.
The passing on of physical or mental characteristics genetically from one generation to another.
