Nutrients cross the membrane wall with the help of protein channels.
<span>Sublimation is the conversion between the solid and the gaseous phases of matter, with no intermediate liquid stage.</span>
The answer is D all of the above
Answer:External respiration occurs in the lungs where oxygen diffuses into the blood and carbon dioxide diffuses into the alveolar air. Internal respiration occurs in the metabolizing tissues, where oxygen diffuses out of the blood and carbon dioxide diffuses out of the cells.
Explanation:
