Ref: online search (Changes to short stretches of nucleotides are called gene-level mutations, because these mutations affect the specific genes that provide instructions for various functional molecules, including proteins. Changes in these molecules can have an impact on any number of an organism's physical characteristics.)
The nervous system help in communication of the body. Therefore, the bbrain is gray, a wrinkly organ and is made up of millions of neurons.
Answer:
a test that automatically scores a person's results as right or wrong
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