Answer: systemic veins and pulmonary arteries; pulmonary veins and systemic arteries
Explanation:
Based on what we have learned so far about the cardiovascular and respiratory systems, blood pH should be lower in the <u>systemic veins and pulmonary arteries</u> compared to the <u>pulmonary veins and systemic arteries</u>.
A symbiosis is an evolved interaction or close living relationship between organisms from different species, usually with benefits to one or both of the individuals involved.
