I believe it would be a fossil of a reptile but I'm not a 100% sure about it.
Answer:
Decrease in available living space
Explanation:
If there is no living space left there will be a decrease in the amount of organisms that can live there
Answer:
genes involved in the cell cycle following a mutation become oncogenes.
Answer:
atomic number
Explanation:
atomic number = proton number = number of protons
Answer:
preventing friction between bones
