Answer:
Arteries carry oxygenated blood away from the heart. Veins carry the blood back to the heart. Veins contain valves that ensure blood flows in only one direction. Arteries don’t require valves because pressure from the heart is so strong that blood is only able to flow in one direction.
Explanation:
Answer:
a gated sodium channels open and sodium ions flood into the cell
<h2>Answer:</h2>
Because same base pairs are arranged differently among organisms due to which there are so much variations in organisms.
<h3>Explanation:</h3>
- Variation in the organism is due to the genes.
- Every one have different DNA/genes which describes one's features.
- Genes are various arrangements of these four base pairs.
So same base pairs with different pattern arrangement causes variation among organism.
Answer:
Kristin's answer is the best.
Explanation:
It is the only correct answer.
