Genetics, double helix, cells
Answer:
Any form of precipitation like rain, snow, fog, hail, and even dust that has acidic components. When the acidity of a lake increases, the water becomes clearer and the all the animals decrease.
Explanation:
The atria and ventricles work together, alternately contracting and relaxing to pump blood through your heart. ... The electrical activity spreads through the walls of the atria and causes them to contract. This forces blood into the ventricles. The SA node sets the rate and rhythm of your heartbeat.
