Choose the correct answer for each question.

1 The Na-K-ATPase Moves 3 sodium molecules into the cell and 2 potassium molecules out of the cell. Prevents action potentials from occuring. Generates an membrane potential that is negative inside compared to outside the cell. Moves 2 sodium molecules out of the cell and 3 potassium molecules into the cell. None of the above. 2 Which of the following does not happen during an action potential? (Consider the entire action potential event). Sodium rushes into the cell through sodium channels. Potassium rushes out of the cell through potassium channels. The membrane potential becomes more positive due to the movement of Na into the cell. The membrane potential becomes more negative due to the movement of potassium out of the cell. All of the above happen during an action potential. 3 Synapses are specialized regions where: A signal from a post-synaptic nerve cell is sent to a presynpatic nerve cell. Signals from presynaptic nerve are passed on to post-synaptic nerve cells. Signals are passed both ways between presynaptic and postsynpatic nerve cells. Sensory information is detected. None of the above. 4 Which of the following is a direct effect of the sympathetic nervous system? Digestive system activity increases. Heart rate slows down. Sweating increases. Drowsiness is induced. None of the above. 5 Which of the following is a convective process? Oxygen moves from a high concentration in the alveolus into the blood stream where it is at a lower concentration. A drop of dye spreads out to become uniformly distributed in a non-stirred cup of water. A simple organism uses tentacles to create a feeding current that brings food molecules towards the mouth. Carbon dioxide diffuses from the tissues into the bloodstream. All of the above are convective processes. 6 Which of the following statements about the partial pressure of oxygen in the alveoli is true? (Assume that only the factors that are stated change). The partial pressure of oxygen in the alveoli will decrease when alveolar ventilation increases. The partial pressure of oxygen in the alveoli will decrease when tissue oxygen use increases. The partial pressure of oxygen is not influenced by alveolar ventilation rate. The partial pressure of oxygen in the alveoli is usually about 40 mmHg in a healthy adult. None of the above is true. 7 In a healthy resting person (not exercising) at sea level, Hemoglobin releases all of its oxygen at the tissue level. Hemoglobin becomes about 75% saturated as it passes through the pulmonary circulation. Hemoglobin remains about 75% saturated with oxygen after it passes through the tissues. Hemoglobin does not need to bind oxygen at all, this is only necessary at altitude and during exercise. None of the above. 8 If the content of red blood cells is decreased, More oxygen will be delivered to the tissues, because there is less hemoglobin to hold it in the circulation. More oxygen will be delivered to the tissues because more spaces will be available in the blood for oxygen. Less oxygen will be delivered to the tissues because less blood will flow through the pulmonary capillaries. Less oxygen will be delivered to the tissues because less oxygen will be picked up by the blood flowing through the pulmonary capillaries. None of the above.