Answer:
If you have anyone of these answer choices..Its D.All of the Above
Explanation:
A. Cells are the structures that contain all of the materials necessary for life
B. Cells are found in all organisms
C. Cells are sometimes specialized for particular functions
D. All of the above
Dna replication so it replicates your DNA to occur
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.
