Compared to arteries, valves have no pulse, have thin walls and have valves that prevent backflow of the blood. The pressure in the veins is less than that of the arteries, hence, there is no pulse. They are nearer to the surface of the skin. It also connects arteries and capillaries which transport blood all throughout the circulatory system.
I prentice that it might kill me and effect me
The endosymbiotic hypothesis concerns the origin of mitochondria and chloroplasts, two organelles contained within various eukaryotic cells. According to this hypothesis, these organelles originated as separate prokaryotic organisms that were taken inside a primordial eukaryotic cell.
The half-life of a radioisotope is the amon the symbol 42He, the subscript 2 is the mass number for helium and the superscript 4 is the atomic number for helium.
