Hello!
The answer would be Alveoli
In humans, oxygen and carbon dioxide are exchanged in the blood within many small sacs called alveoli in the lungs. Alveoli provide a large surface area for gas exchange.
Hope this helped!
Hi .says the awser is Volcanic neck,Batholith,Dome mountain. I hope this help you!
Specialized proteins in the cell membrane regulate the concentration of specific molecules inside the cell. ... Transporters carry a molecule (such as glucose) from one side of the plasma membrane to the other. Receptors can bind an extracellular molecule (triangle), and this activates an intracellular process.
Man i hate school that really makes my head hurt