Answer:
D. Organs and muscles require more blood under stress.
Explanation:
Because muscular contractions can have a protracted metabolic expenditure because it has to be adjusted to the demands of the contracting muscles.
The somatic nervous system I think
To prevent allergic reactions.
Answer: It's because he/she is constantly subjecting their legs to gravity, which veins are fighting against to move blood back to the heart.
Answer:
Acids lower the pH of freshwater and bases raise the pH of freshwater.
Explanation:
If a substance is too basic, it could possibly harm another organism living in the freshwater source. If it's too acidic, it could possibly make unsafe living conditions in that environment. That's why you should always check the pH level in the fish tank and in the pool to see what the pH is. A pH of 6 - 8 is always safe for fish, whereas a pH of 5 - 9 is safe for pools.
Explanation:
Acids: 0 - 6
Neutral: 7
Bases: 8 - 14
