The SA node is the normal pacemaker of the heart because the SA node _______.
1. can form action potentials that can spread throughout the rest of the heart
2. depolarizes to its threshold potential before other pacemakers in the heart
3. forms a functional syncytium, transmitting action potentials to neighboring cardiac
fibres
4. is most likely to form an ectopic foucus
The time taken for an impulse to travel from the S-A to the A-v node is evidenced in the ___.
1. QRS complex
2. S-T interval
3. P-Q interval
4. QRS-T interval
Which condition is characterized by an abnormal increase in red blood cell count?
1. polycythemia
2. anemia
3. leukemia
4. porphyria
Who is at risk for developing a fatal Rh incompatibility?
1. any Rh+fetus
2. second Rh-fetus of Rh+moter
3. second Rh+fetus of Rh-mother
4. Rh-mother
Blood pressure is the pressure of blood against ___.
1. a stethoscope
2. the skin of the upper arm
3. the capillaries of the lung
4. the wall of a blood vessel
The largest of the white blood cells are the ____
1. neutrophils
2. monocytes
3. macrophages
4. lymphocytes
Which one of the following series represents the correct path of blood circulation?
1. left atrium, left ventricle, lungs, right atrium, right ventricle, body
2. right atrium, right ventricle, lungs, left atrium, left ventricle, body
3. left atrium, left ventricle, right atrium, right ventricle, lungs, body
4. right atrium, lungs, right ventricle, left atrium, body , left ventricle
5. left atrium, lungs, left ventricle, body, right atrium, right ventricle
Choose the correct statement.
1. Blood pressure in the pulmonary capillaries is lower than blood pressure in the systemic capillaries.
2. Blood pressure in the pulmonary trunk is higher than blood pressure in the aorta.
3. More blood is pumped through the systemic circulation each minute than is pumped through the pulmonary circulation.
4. Pulmonary circulation is powered by the left side of the heart.
Venous return would be increased by
1. dilation of the veins.
2. loss of the venous valves.
3. increased skeletal muscle activity.
4. decreased respiratory rate.
Which of these pressures pulls water into capillaries?
1. blood hydrostatic pressure
2. blood colloid osmotic pressure
3. interstital fluid pressure
4. interstitial colloid osmotic pressure
Action potentials pass from one cardiac muscle cell to another
1. through gap junctions.
2. by a special cardiac nervous system.
3. because of the large voltage of the action potentials.
4. because of the plateau phase of the action potentials.
5. by neurotransmitters.
The greatest amount of ventricular filling occurs during
1. the first one-third of diastole.
2. the middle one-third of diastole.
3. the last one-third of diastole.
4. ventricular systole.
While the semilunar valves are open during a normal cardiac , the pressure in the left ventricle is
1. greater than the pressure in the aorta.
2. less than the pressure in the aorta.
3. the same as the pressure in the left atrium.
4. less than the pressure in the left atrium.
If the SA node becomes damaged and nonfunctional, which of these is the most likely to occur?
1. The heart will stop.
2. The ventricles will contract, but the atria will stop.
3. Another part of the heart, possibly the Av node, wil become the pacemaker.
4. The heart will beat faster.
5. The atria will keep contracting, but the ventricles will stop.
Pernicious anemia is an example of
1. hypochromic anemia.
2. nutritional anemia.
3. hemorrhagic anemia.
4. hemolytic anemia.
For someone having a coronary thrombosis (blockage of a coronary artery by a blood
clot), which of these chemicals is the most effective to inject?
1. histamine
2. thrombin
3. thromboxane
4. t-PA
Which of these statements about the ABO blood group is NOT true?
1. A person with type O blood can donate blood to individuals with type A, B, AB, or O
O blood types.
2. Transfusions should be made considering the plasma of the donor and the
erythrocytes of the patient (recipient).
3. A person with type A blood shoud not receive a transfusion from someone with type
AB blood.
4. A person with type O blood has both the A and B antigens.
The veins of the gastrointestinal tract all merge into some part of the _____ . which
shunts the blood to the liver for absorption and processing of transported materials.
1. renal portal system
2. hepatic anastomosis
3. hepatic portal system
4. gastrointestinal plexus
The _____ are to the walls of large blood vessels as the coronary vessels are to the myocardium.
1. nutrient arteries and veins
2. continous capillaries
3. fenestrated capillaries
4. vasa vasorum
A type of heart murmur called mitral valve prolapse would most likely involve a defect in
1. the size or shape of the right atrioventricular opening
2. the left chordae tendineae or papillary muscles
3. one of the three cusps of the tricuspid valve
4. the structure of either semilunar valve
How can Rh antibodies, the very molecules that cause hemolytic disease of the
newborn, prevent this disease when administered to an Rh negative woman who is
pregnant with an Rh positive fetus?
1. the antibodies cross the placenta early in development and desesitize the fetus's
blood
2. presence of the antibodies transforms the fetus into an Rh negative individual
3. the antibodies destroy any Rh antigens from the fetus before the mother is
sensitized
4. none of the aove; an Rh negative woman cannto have an Rh positive child