Any characteristic, whether a physical trait, a behaviour, a physiological adaptation etc can make an organism more or less likely to survive in a particular environment.
A dark colour could help a rabbit survive if it lives in a dark forest, because predators can't see it so well, but it would be less likely to survive in the arctic, where the environment is all white and it would show up.
In terms of the characteristics, think about: does it help the organism get food? Does it help protect the organism from predators? If it does, that organism is more likely to survive, and pass the characteristic on to it's offspring. If a bacterium has a characteristic of not being killed by antibiotics, this will help it to survive and breed.
We consider them to be made of 3 quarks, 'uud' for the proton<span> and 'udd' for the</span>neutron<span> where 'u' is the up quark and 'd' the down quark. ... Now, </span>protons and neutrons<span> are basically found at the atomic nucleus while </span>electrons<span> form the shell of the atom, moving around the nucleus.</span>
It starts with the cells<span>, followed by the tissues, then the organs, and ending with the organ .</span>
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A pollutant that can reduce the amount of oxygen carried by blood is carbon monoxide.
I hope this helps.
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