The answer is C.
It is the site of gas exchange in the lungs.
Gas exchange occurs only in alveoli. Alveoli are made of thin-walled parenchymal cells, typically one-cell thick, that look like tiny bubbles within the sacs. Alveoli are in direct contact with capillaries (one-cell thick) of the circulatory system.
Answer:
option 1 and 4
Explanation:
It flows from high pressure to low pressure as air is made up of gases and gases move according to the process of diffusion.
It moves from lower density to higher density as pressure is inverse to density. As density is not what makes the air move it is pressure.
Answer:
the pattern will be logistic
The level of electrons involved is equal to its valency....
About 95% of the time down syndrome is caused by “trisomy 21.”the person has three copies of chromosome 21, instead of the usual two copies, in all cells. This is caused by abnormal cell division during the development of the sperm cell or the egg cell.