Answer:
B 20 amino acids, hundreds of proteins
Explanation:
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One way is that Igneous rock could erode and become sediment and deposited and slowly change into sedimentary rock, then get pushed down deep into the crust and changed by heat and pressure into metamorphic rock.
The brain which, along with the spinal cord gathers informationand responds to changes in the environment.
Answer:
Everything at some point belonged to a common ancestor, but these four species are considered to be like this because of similar ancestral traits that have been passed on to generations such a homologous pairs, vestigial structures, they are all mammals, similar amino acid sequences, vertebraes, etc.