Valves ensure blood flows toward your heart. Vein valves work to bring the blood that flowed down via arteries back up to your heart.
Answer:
it's called condensation
Explanation:
When warm air hits the cold surface, it reaches its dew point and condenses. This leaves droplets of water on the glass or can. When a pocket of air becomes full of water vapor, clouds form.
<span>Protein is made up of building blocks called amino acids</span>
Answer:
B) plants get the energy they need for photosynthesis from sunlight
Explanation: