Answer:
When CO2 is breathed into the lungs, it dissolves in the water there, diffuses across the alveolar-capillary membrane, and enters the bloodstream. As it combines with water, it forms carbonic acid, making the blood acidic. So CO2 in the bloodstream lowers the blood pH.
The correct terms to fill in the blanks would be contracts and dilates. In stressful situations, the sympathetic nervous system contracts the arteries of the circulatory system resulting to the dilation of the pupils of the eyes. Also, during these situations, the blood sugar levels are raised since the hormones for stress kick in to combat the stress which in turn raises the blood sugar.
Enzymes can be destroyed by variations in temperature or pH
<span>Eats plants only: Herbivore
Eats animals only: Cornivore
Eats plants and animals: Omnivore </span>
I think the correct answer is d