Answer:
consisting of one new and one old chain of nucleotides.
is described as semi-conservative, half of the chain is part of the original DNA molecule, half is brand new.
I believe the answer is (B) Parasitic.
Answer:Valves stop blood flowing backwards
Explanation: Valve are flags of tissue that control the direction of the blood in our heart.,it prevent the backwards flow of blood. valves regulate blood from flowing back into the atria.The right and left atrio-ventricular valves prevent blood from flowing backwards into atria. When the ventricle is full,the valve prevent backwards flow of blood.
Every plant organ is adapted to its function. For example, leaves that are big and flat absorb plenty of sunlight for photosynthesis. Long roots keep a tree stable and take water from deep in the soil. Some plants have unusual adaptations.