I guess that is:
Within the capillaries of the lungs, gases are exchanged by diffusion; O2 diffuses from the alveolus to the bloodstream and CO2 diffuses from the bloodstream to the alveolus.
The basic repeating unit of nucleic acids are known as nucleotides. A nucleotide consists of three distinct chemical groups, a 5-carbon sugar (ribose or deoxyribose), a nitrogen-rich base - (cytosine (C), guanine (G), adenine (A), thymine (T) in DNA or uracil (U) instead of T (in RNA), and phosphate.
yes,because with no qualification you can not make the right choice when voting
