First blank - phenotype
second blank - alleles
Answer: natural selection
Explanation: Maybe because the A woodpecker was able to adapt a lot easier than the woodpecker B and its evolution was better
Answer:
These organelles are contractile vacuoles
Explanation:
Contractile vacuoles are intercellular pumps that are slowly filled with fresh water and eventually expel their contents outside the cell. Freshwater protists maintain the hydric equilibrium by contractile vacuoles that pump out the water of the cell and thus prevent the cell swelling induced by osmotic stress.