Neutrons have no charge. This means the nucleus of an atom is always positively charged. An atom has a neutral overall charge because it has the same number of electrons as protons.
Answer:
Oxygen-rich blood flows from the lungs back into the left atrium (LA), or the left upper chamber of the heart, through four pulmonary veins. Oxygen-rich blood then flows through the mitral valve (MV) into the left ventricle (LV), or the left lower chamber.
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The blood becomes oxygenated in the lungs. Oxygenated blood leaves the lung via the pulmonary vein. Blood moves into the left ventricle. Blood is pumped into the aorta, which carries oxygenated blood around the body.
Answer: [A]: "to make their food" .
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For the answer to the question above, <span>Griffith heated a culture of a disease- causing the strain of the bacteria, which killed the bacteria but didn't destroy the DNA. When he mixed the heat-killed, disease-causing bacteria with live harmless bacteria, the DNA from the disease-causing bacteria was infused to the live bacteria. This kind of bacteria and their offspring caused pneumonia to the mice.</span>
Choaocytes are responsible for generating water currents the faciliate gas exchange and nutrition
