PATHOPHYSIOLOGY THE BIOLOGIC BASIS FOR
DISEASE PREMIUM REVIEW SET 2026
PRACTICE SOLUTION GUARANTEED PASS
◉ pericardial sac function. Answer: 1. prevents displacement of
heart during gravitational acceleration or deceleration
2. acts as a physical barrier that protects the heart against infection
and inflammation from the lungs and pleural space
3. contains pain receptors and mechanoreceptors that can elicit
reflex changes in blood pressure and heart rate
◉ parietal pericardium. Answer: -outer layer of pericardium
-composed of a surface layer of mesothelium over a thin layer of
connective tissue
◉ visceral pericardium aka epicardium. Answer: -inner layer of
pericardium
-folds and becomes continuous with parietal pericardium, allowing
large vessels to enter and leave the heart without breaching the
pericardial layers
◉ pericardial cavity. Answer: fluid-containing space separating the
visceral and parietal pericardia
,◉ pericardial fluid. Answer: -secreted by cells if the mesothelium
-lubricates the membranes that line the pericardial cavity, enabling
them to slide over one another with a minimum of friction as the
heart beats
-amount and character are altered by inflammation of the
pericardium
◉ epicardium. Answer: -outer layer of the heart
-provides a smooth surface that allows the heart to contract and
relax within the pericardium with a minimal amount of friction
◉ myocardium. Answer: -thickest layer of heart wall
-composed of cardiac muscle and anchored to the heart's fibrous
skeleton
-thickness varies greatly from one heart chamber to another-related
to the amount of resistance the muscle must overcome to pump
blood from the different chambers
◉ endocardium. Answer: -internal lining of myocardium
-composed of connective tissue and a layer of squamous cells
-continuous with the endothelium that lines all the arteries, veins,
capillaries of body; creating a continuous, closed circulatory system
,◉ four chambers of heart. Answer: right atrium, left atrium, right
ventricle, left ventricle
◉ which are smaller-atria or ventricles?. Answer: Atria are smaller,
with thinner walls. Low pressure chambers that serve as storage
unit and conduits for blood that is emptied into the ventricles.
Ventricles have thicker myocardial layer and make up bulk of heart.
Ventricles must propel blood all the way through the pulmonary or
systemic circulation.
◉ What forms the ventricles?. Answer: A continuum of muscle fibers
that originate from the fibrous skeleton at the base of the heart.
◉ Which ventricle's myocardial wall is thicker, and why?
How much arterial pressure must each side overcome?. Answer: The
left ventricle's myocardial wall is thicker because the pressure is
markedly higher in systemic circulation.
The right ventricle must overcome 15 mmHg pressure, the left
ventricle must overcome 92 mmHg pressure.
, ◉ inflow tract. Answer: -area of ventricle to receive blood from the
atrium
-formed by muscle fibers
◉ outflow tract. Answer: -area of ventricle to send blood to the
circulation
-formed by muscle fibers
◉ Normally blood does not flow between the chambers of the heart
because the two sides are separated by intact septal membranes.
What is the normal exception?. Answer: In the fetus, prior to
delivery. (foramen ovale)
◉ annuli fibrosi cordis. Answer: central, supporting structure of
heart
◉ What ensures one way blood flow through the heart?. Answer: 4
valves and the pressure gradients they maintain.
◉ atrioventricular valves (tricuspid and mitral). Answer: -during
ventricular relaxation, AV valves open and blood flows from the
relatively higher pressure in the atria to lower pressure in the
relaxed ventricles
-increasing ventricular pressure closes the valves and prevents back
flow into the atria as the ventricles contract
DISEASE PREMIUM REVIEW SET 2026
PRACTICE SOLUTION GUARANTEED PASS
◉ pericardial sac function. Answer: 1. prevents displacement of
heart during gravitational acceleration or deceleration
2. acts as a physical barrier that protects the heart against infection
and inflammation from the lungs and pleural space
3. contains pain receptors and mechanoreceptors that can elicit
reflex changes in blood pressure and heart rate
◉ parietal pericardium. Answer: -outer layer of pericardium
-composed of a surface layer of mesothelium over a thin layer of
connective tissue
◉ visceral pericardium aka epicardium. Answer: -inner layer of
pericardium
-folds and becomes continuous with parietal pericardium, allowing
large vessels to enter and leave the heart without breaching the
pericardial layers
◉ pericardial cavity. Answer: fluid-containing space separating the
visceral and parietal pericardia
,◉ pericardial fluid. Answer: -secreted by cells if the mesothelium
-lubricates the membranes that line the pericardial cavity, enabling
them to slide over one another with a minimum of friction as the
heart beats
-amount and character are altered by inflammation of the
pericardium
◉ epicardium. Answer: -outer layer of the heart
-provides a smooth surface that allows the heart to contract and
relax within the pericardium with a minimal amount of friction
◉ myocardium. Answer: -thickest layer of heart wall
-composed of cardiac muscle and anchored to the heart's fibrous
skeleton
-thickness varies greatly from one heart chamber to another-related
to the amount of resistance the muscle must overcome to pump
blood from the different chambers
◉ endocardium. Answer: -internal lining of myocardium
-composed of connective tissue and a layer of squamous cells
-continuous with the endothelium that lines all the arteries, veins,
capillaries of body; creating a continuous, closed circulatory system
,◉ four chambers of heart. Answer: right atrium, left atrium, right
ventricle, left ventricle
◉ which are smaller-atria or ventricles?. Answer: Atria are smaller,
with thinner walls. Low pressure chambers that serve as storage
unit and conduits for blood that is emptied into the ventricles.
Ventricles have thicker myocardial layer and make up bulk of heart.
Ventricles must propel blood all the way through the pulmonary or
systemic circulation.
◉ What forms the ventricles?. Answer: A continuum of muscle fibers
that originate from the fibrous skeleton at the base of the heart.
◉ Which ventricle's myocardial wall is thicker, and why?
How much arterial pressure must each side overcome?. Answer: The
left ventricle's myocardial wall is thicker because the pressure is
markedly higher in systemic circulation.
The right ventricle must overcome 15 mmHg pressure, the left
ventricle must overcome 92 mmHg pressure.
, ◉ inflow tract. Answer: -area of ventricle to receive blood from the
atrium
-formed by muscle fibers
◉ outflow tract. Answer: -area of ventricle to send blood to the
circulation
-formed by muscle fibers
◉ Normally blood does not flow between the chambers of the heart
because the two sides are separated by intact septal membranes.
What is the normal exception?. Answer: In the fetus, prior to
delivery. (foramen ovale)
◉ annuli fibrosi cordis. Answer: central, supporting structure of
heart
◉ What ensures one way blood flow through the heart?. Answer: 4
valves and the pressure gradients they maintain.
◉ atrioventricular valves (tricuspid and mitral). Answer: -during
ventricular relaxation, AV valves open and blood flows from the
relatively higher pressure in the atria to lower pressure in the
relaxed ventricles
-increasing ventricular pressure closes the valves and prevents back
flow into the atria as the ventricles contract
