Bio 150 exam 3 (lecture)

• Which of the following proteins is not normally found in plasma?

  Hemoglobin
• The pulmonary circuit is supplied by both the right and the left sides of the heart.

  Group starts

  false
• The systemic circuit contains oxygen-rich blood only.

  false
• Which of the following carry oxygen-poor blood?

  Venae cavae and pulmonary arteries
• Which of the following belong to the pulmonary circuit?

  Pulmonary arteries and pulmonary veins
• The heart is enfolded within a space called the _________blank.

  pericardial cavity
• The apex of the heart is found _________blank of the midline of the body.

  to the left
• Which of the following is the most superficial layer enclosing the heart?

  Fibrous pericardium
• Pericardial fluid is found between the _________blank and the _________blank.

  parietal layer of the serous pericardium; visceral layer of the serous pericardium
• The fibrous skeleton of the heart serves as electrical insulation between the atria and the ventricles.


  True
• The _________blank performs the work of the heart.

  myocardium
• The _________blank are the superior chambers of the heart and the _________blank are the inferior chambers of the heart.

  atria; ventricles
• The ventricles are the thicker more powerful chambers of the heart. They pump blood to the lungs and body.

  True
• The shallow depression seen on the external surface of the heart between the left and right ventricles is called the _________blank.

  interventricular sulcus
• The area where the major vessels lead to and from the heart's chambers is called the _________blank of the heart. The pointy, inferior portion is called the _________blank.

  base; apex
• The right atrioventricular valve regulates the opening between the _________blank and the _________blank.

  right atrium; right ventricle
• The _________blank valve regulates the flow of blood between the right ventricle and the vessels leading to the lungs.

  pulmonary
• The chordae tendineae of the AV valves are anchored to the _________blank of the ventricles.

  papillary muscles
• Which of the following directly stems from the ascending aorta before it branches into the circumflex branch and anterior interventricular branch?

  Left coronary artery
• Blood in the heart chambers provides most of the myocardium's oxygen and nutrient needs.

  False
• Cardiac muscle can only use glucose as a source of organic fuel.

  False
• Which of the following is not a feature of cardiac muscle?

  They have about the same endurance as skeletal muscle fibers.
• Desmosomes form channels that allow each cardiomyocyte to electrically stimulate its neighbors.

  False
• Electrical signals pass between cardiomyocytes through the _________blank.

  gap junctions
• The _________blank is the pacemaker that initiates each heart beat.

  sinuatrial (SA) node
• Which of the following is not part of the cardiac conduction system?

  Tendinous cords
• Which is the correct path of an electrical excitation from the pacemaker to a cardiomyocyte in the left ventricle (LV)?

  Sinuatrial (SA) node → atrioventricular (AV) node → atrioventricular (AV) bundle → subendocardial branches → cardiomyocyte in LV
• The pacemaker potential is a result of _________

  Na+ inflow
• If the SA node is damaged, nodal rhythm is sufficient to sustain life.

  True
• If the sinuatrial (SA) node is damaged, the heart will likely beat at _________blank bpm.

  40 to 50
• Cells of the sinuatrial node _________blank during the pacemaker potential.

  depolarize slow
• The plateau in the action potential of cardiac muscle results from the action of _________blank.

  slow Ca2+ channels
• The _________blank provides most of the Ca2+ needed for myocardial contraction.

  sarcoplasmic reticulum
• Any abnormal cardiac rhythm is called a(n) _________blank.

  arrhythmia
• Atrial depolarization causes the _________blank.

  P wave
• Blood pressure is usually measured in millimeters of mercury (mmHg) but could be measured with any liquid, such as water (mm H20 ).


  True
• Mercury is used to measure blood pressure because it is _________ compared to other liquids.

  more dense
• Papillary muscles prevent the AV valves from prolapsing (bulging) excessively into the atria when the ventricles contract.

  True
• When the left ventricle contracts, the _________ valve closes and the _________ valve is pushed open.

  mitral; aortic
• Which is the correct sequence of events of the cardiac cycle?

  Ventricular filling → isovolumetric contraction → ventricular ejection → isovolumetric relaxation