Observable traits exhibited by an organism do not always indicate the exact genetic makeup of that organism . Which explains this ?

Describe the response the kidneys have to dehydration and excessive water intake. what happens to the concentration of urine in each case ?

How does upwelling affect coastal fisheries? upwelling damages nutrient supplies at coastal fisheries as the warm, nutrient-rich surface water is replaced by nutrient-poor, cold water. upwelling damages nutrient supplies at coastal fisheries as the cold, nutrient-rich surface water is replaced by nutrient-poor, warm water. upwelling improves the nutrient supply at coastal fisheries as the warm, nutrient-rich surface water replaces the nutrient-poor, cold water. upwelling improves the nutrient supply at coastal fisheries as cold, nutrient-rich water replaces the warm, nutrient-poor surface water.

Which of these is not a nucleotide base found in dna?