5 Written questions
5 Matching questions
- Chordae tendineae
- Voltage-gated K+ channels
- Third heart sound
- Cardioacceleratory center
- a Slows and strengthens contractions of the heart muscle by increasing the amount of Ca2+ that enters cardiac muscle cells and by prolonging the action potentials' refractory period.
- b Several types exist, each of which opens and closes at different membrane potentials, causing changes in membrane permeability to K+.
- c Tendinous strands running from the papillary muscles to the atrioventricular valves. The papillary muscles are attatched by thin, strong connective tissue strings.
- d The part of the cardioregulatory center that increases heart rate.
- e can be heard in some normal people, particularly those who are thin and young.
5 Multiple choice questions
- The Cardiac muscle cell is completely insensitive to further stimulation. Portion of the action potential during which the membrane is insensitive to all stimuli, regardless of their strength.
- Electric charge difference inside a plasma membrane, measured relative to just outside the plasma membrane.
- the larger, flat part at the opposite end of the heart; the flat portion directed posteriorly and superiorly.
- The part that decreases heart rate.
- is the pressure the contracting left ventricle must produce to overcome the pressure in the aorta and move blood into the aorta.
5 True/False questions
Intrinsic regulation → Prevent clot formation in people who have damaged heart valves or blood vessels or I those who have had a myocardial infarction.
Arterial systole → means to dilate. Relaxation of the heart chambers, during which they fill with blood; usually refers to ventricular relaxation.
Cardioregulatory center → Where sensory action potentials are integrated.
Artificial heart → is an instrument, placed beneath the skin, equipped with an electrode that extends to the heart and provides an electrical stimulus at a set frequency.
Mean Arterial pressure (MAP) → is the total resistance against which blood must be pumped.