Answer: Possession of Valves
Explanation: Veins possess valves which ensures that blood flows in only one direction. Valves helps blood to flow back to the heart against gravitational force.
Arteries don't have valves because the pressure originating from the heart is capable of causing the blood to flow in one direction.
The number of chromosomes will be haploid as opposed to diploid so you will end up with 5 chromosomes
Coal, Natural Gas, and Putroleeum?oil
Bones: they lose calcium, becoming crispy
Muscle: they lose mass
Cartilage: becomes stiffer, but it does not make airway more rigid
D) connective tissue: It includes bone, blood, and lymph tissue, giving support to the skin and internal organs, becoming increasingly stiff when aging.
It should be connective tissue.