The keyword here is "area per volume" which is available in both cases. Besides capillaries are smaller than arteries they have in total more area as there are many vessels of then. The More the area/volum, the less the velocity
Well for the very last sentence it would be if any of the organs shut down it could seriously hurt someone or possibly even kill them if their brain,heart or some other important organ shuts down it could kill them.
There are other minor organs where if it shuts down it wouldn't really hurt the person too much. Sorry I couldn't help you with the other ones though.
True. Greenhouse gases are composed of many molecular components that provide and are necessary for life to still exist on earth. For example, the carbon dioxide and the others alike. However, when these exceed the necessary level and amount in the atmosphere, they cause tremendous increase in temperature.
The membrane is selectively permeable because substances do not cross it indiscriminately. Some molecules, such as hydrocarbons and oxygen can cross the membrane. Many large molecules (such as glucose and other sugars) cannot. Water can pass through between the lipids.
