How does oxygen move from the respiratory system to the circulatory system?
O A. By moving across a synapse
O B. By pumping through the heart
O C. By circulating in an artery
D. By diffusion across a capillary wall

D. By diffusion across a capillary wall

Explanation:

D is the best answer because gas exchange takes place in our lungs. Our lungs have alveoli which have a network of tiny blood vessels called capillaries, here the O2 diffuses the capillary wall to enter the bloodstream, and similarly CO2 diffuses out and we exhale it our from our lungs.

the answer for apex is "1 and 6"

small, big, or no change could occur in the phenotype. it could cause something as simple as a cats ears to curl backwards or something as frighting as death. it could also occur in the protien-coding area and have an effect on that but no effect on the amino acids. what has to occur is a changing in the hox gene or the control gene.