Structure of the Heart
What valve is located between the right ventricle and pulmonary trunk?
pulmonary semilunar valve
Where do the left atrium get blood from and is the blood oxygenated? Where does blood get pumped to?
received oxygenated from the lungs,
Pumps to the left ventricle
Why do the pulmonary arteries branch immediately outside the heart?
One goes to each lung
Which vessel carries blood away from the heart? Which one carries blood to the heart?
Arteries then veins
What is inflammation of the endocardium?
endocarditis
What are the serous membranes of the heart? What type of tissue are each?
Outermost: Fibrous pericardium: thick connective tissue
Outer: parietal serous membrane (forms the pericardium)
Inner: visceral serous membrane (epicardium)
What is the function of the heart valves?
prevent backflow and ensure one-way blood flow
What are the three sizes of arteries from largest to smallest?
elastic artery, muscular artery, arteriole
What is the difference between systemic and pulmonary capillaries?
Gas/nutrient exchange between the body cells
Gas/nutrient exchange in the lungs
What is a myocardial infarction? What causes it?
BONUS!! What symptom is found in women but not men
-also known as a heart attack
-lack of blood supply to the heart causing lack of oxygenation causes death of cardiac muscle
-caused by blockage in coronary arteries
BONUS!!
Women feel nauseous, light headed and tired
The heart wall itself is composed of three membranes, describe their respective locations and the type of tissues they are composed of.
epicardium (outer): simple squamous epithelium, aereolar connective tissue, and adipose connective tissue
Myocardium (middle): cardiac muscle
endocardium (inner): areolar connective tissue and simple squamous epithelium
What attaches the valves to the ventricle wall? What are their function?
tendinous cords; allows the valves to open the correct direction and keeps the valves closed when there is no contraction
Describe the systemic circulation path
L atrium > L ventricle > aorta > systemic arteries > body >systemic veins > superior and inferior vena cava
What great vessel drains deoxygenated blood into the right atrium?
Venae Cavae
What is fibrillation?
BONUS: What can we do to fix fibrillation? How does this fix the issue?
uncoordinated contraction leading to poor blood flow
BONUS: shock the heart to restart the AV node with a defibrillator
What are the specialized muscle fibers that help transmit electrical conduction in the heart?
Purkinje fibers/ subendocardial branches
what is cardiomegaly? How is contraction affected?
enlarged heart; sarcomere filaments don't overlap properly which reduces contraction
What are the structural differences between arteries and veins?
Arteries:
thicker walls, narrower lumen, more collagen, more elastic fibers, tunica media is thickest
Veins:
tunica externa is thickest, contain valves
What are the three major types of capillaries? How close are their cells?
BONUS: Name one type of tissue for each type.
continuous: tightly connected
fenestrated: openings (fenestrations) between cells and within the cells
sinusoid (discontinuous): large openings
BONUS:
Continuous: most in skin, muscle, lungs, brain, etc
Fenestrated: small intestine, most endocrine glands, kidneys, choroid plexus, ciliary process
Sinusoid: red bone marrow, liver, spleen, Endocrine glands: (anterior pituitary, adrenal, parathyroid)
Draw the standard waves in an ECG for one heart cycle.
Include the polarization events of the heart for each of the waves/complexes only (do not include segment polarization events).
small peak P wave: atrial depolarization
q dip, spike R, dip S (QRS complex): ventricular depolarization
small peak T wave: ventricular repolarization
Describe the steps of initiating action potential in the SA nodal cell. (Hint: 4 Steps)
1. Na+ enters the cation channels
-hit the threshold of -40mV (from resting -60mV)
2. Ca2+ channels open and Ca2+ enters resulting in depolarization
- -40mV to just above +0 potential
3. K+ channels open > K+ exits
-repolarization; potential goes from 0 back to -60mV
4. Almost immediately hit threshold again to allow action potential
What does cocaine do to your heart rate? How?
inhibits the reuptake/ reabsorption of norepinephrine; keeps the heart rate high
What are the three layers of blood vessels? What are the sublayers of each? What type of tissues are each?
tunica intima:
endothelium (epithelial), sub endothelial (connective), internal elastic (connective)
tunica media:
smooth muscle
Between media and externa: external elastic (connective)
tunica externa:
vasa vasorum (capillaries that feed larger blood vessels)
What affects stroke volume? (Hint: 3 factors)
-End diastolic volume (high EDV = high stroke volume)
-afterload (high after load = high resistance = decreased stroke volume
-inotropic agents (positive agents = increase stroke volume and negative agents = decrease stroke volume)
What does epinephrine do to the SA nodal cell? What is its receptor, the cascade and final effect?
The SA nodal cell has a beta-adrenergic receptor > leads to G protein activation > activates adenylate cyclase > adenylate cyclase converts ATP to cAMP > cAMP activates protein kinase > protein kinase opens calcium channels > Ca can now enter the cell