Answer:
Arteries carry oxygenated blood away from the heart. Veins carry the blood back to the heart. Veins contain valves that ensure blood flows in only one direction. Arteries don’t require valves because pressure from the heart is so strong that blood is only able to flow in one direction.
Explanation:
Answer:
D) Pressure from water that flows into the plant cells
Explanation:
Answer:
Enzymes function best at specific pH and temperatures.
Explanation:
An enzyme can be defined as a biological catalyst that typically lowers the activation energy of a biological reaction. When the activation energy of a reaction is low, the rate of the reaction would be faster. Therefore, an enzyme speeds or catalyzes the rate of a reaction by lowering its activation energy.
Also, if the conditions are not optimal for an enzyme, it limits the ability of an enzyme to bind or be joined with its substrates.
Hence, the correct statement about enzymes is that enzymes function best at specific pH and temperatures. An increase in temperature increases or speeds up the rate of a reaction while low temperature limits or reduces the rate of a reaction. The optimal temperature for enzymes in the human body is around 37 degrees celsius.
<span>Distance is a scalar quantity that refers to "how much ground an object has covered" during its motion. Displacement is a vector quantity that refers to "how far out of place an object is"; it is the object's overall change in position.</span>