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.
Answer:
18:repeat the experiment again
Explanation:
Because repeating the experiment would get rid of inaccurate data
I believe they are stromal
Part A:
<span>If early conditions of primeval earth had ammonia, methane, hydrogen in its atmosphere, then it is possible that amino acids such as glycine, α-alanine, and β-alanine may have been spontaneously formed from chemical reactions spurred by energy from lightning.</span>
<span>Their hypothesis was that the early conditions of primeval earth favored the spontaneous formation of organic molecules, from inorganic precursors, that may have been the origin of life. This theory is called abiogenesis. </span>
Part B:
<span>Miller Urey put methane, ammonia, hydrogen gases in a glass flask and a pool of water at the bottom of the glass flask. The flask was heated moderately to simulate the hot conditions then. Sparks were also occasionally induced in the flask to mimic lighting. The flask was then cooled slowly to simulate cooling of earth over time.After one day, they found the presence of some amino acids (glycine, α-alanine and β-alanine) was discovered in the water in the flask</span>
