Answer: a. Increasing the surface area for diffusion
Explanation:
When the air is inhaled through the nostrils, the air containing the oxygen the air diffuses inside the alveoli. The alveoli are the tiny sacs where air enters and exchange of gases takes place. From the alveoli the oxygen enters into the blood stream. The oxygen is utilized by the cells for respiration. The increase in network and number of the alveoli will increase the surface area for the diffusion of oxygen and hence, will speed up the respiration process.
I think it's the nucleus. Isn't the nucleus the brain of the cell?
I belive that the emperor penguin fits all the criteria of Group B.
After seeing the attached picture represented above, it has become more clear and I think that the best explanation for why the onion cells do not burst, while red blood cells often do, is that t<span>he red blood cells have only a cell membrane, which does not protect them from bursting. The main point which makes difference between two parts of picture is that one of the cells has protective membrane.
Hope you will find it helpful.
Regards.</span>
