Veins .

produce red blood cells
are only found in the heart
usually carry deoxygenated blood
carry blood away from the heart

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what statement best describes the difference between the sympathetic and parasympathetic nervous systems?

the sympathetic nervous system prepares the body for intense physical activity and is often referred to as the fight-or-flight response. the parasympathetic nervous system has almost the exact opposite effect and relaxes the body and inhibits or slows many high energy functions.

the generally accepted parts of modern cell theory include: all known living things are made up of one or more cells. all living cells arise from pre-existing cells by division. the cell is the fundamental unit of structure and function in all living organisms.

not only is it colder, it also becomes darker, less salty, and more dense.

if someone had the list of traits you provided