A
The cardiac centers monitor baroreceptors and chemoreceptors innervated by which 2 cranial nerves?
Glossopharyngeal Nerve (CN IX) & Vagus Nerve (CN X)
Contraction of which muscles pull the chordae tendineae?
Papillary muscles
What is the name of the region located between the two plural cavities that the heart is positioned in?
Mediastinum
1. Which type of blood vessels carry blood towards the heart?
2. Which type of blood vessels carry blood away from the heart?
1. Veins
2. Arteries
What is tachycardia?
Abnormally fast resting heart rate
How is cardiac output calculated?
CO (mL/min) = HR (beats/min) x SV (mL/beat)
Where are the cardiac centers which contain the headquarters for autonomic cardiac control located in the brain?
Medulla Oblongata
What is the most common cause of a heart attack?
Coronary artery disease & Coronary Thrombosis
What are the 2 great veins that bring blood directly to the heart?
Superior Vena Cava & Inferior Vena Cava
1. What is another name for the aortic valve?
2. Which vessels receive the blood that passes through the aortic valve?
1. Aortic semilunar valve
2. Aorta
Which 3 hormones increase heart rate by their effects on cells in the SA node?
Epinephrine, Norepinephrine, & Thyroid hormone
Which blood vessels bring blood to the left atrium?
The two left & two right pulmonary veins
What is the function of the mitral (bicuspid) valve?
Guards the entrance to the left ventricle
Which type of cardiac arrhythmia is responsible for the condition known as cardiac arrest?
Ventricular Fibrillation
What is the function of the systemic circuit?
It carries blood between the heart and the tissues of the body
1. What is stroke volume?
2. How is stroke volume calculated?
1. Stroke volume is the amount of blood ejected by the ventricle during systole
2. SV = EDV -ESV
What are the three layers of the heart from superficial to deep?
Epicardium --> Myocardium --> Endocardium
What is the structure and function of septa?
Septa is a muscular partition, it separates the chambers of the heart
What is autorhythmicity?
Ability of the cardiac muscle tissue to contract without neural or hormonal stimulation
What is the function of intercalated discs?
Hold membranes of adjacent cells and transfer the force of contraction (desmosomes), Propagated action potentials (gap junctions)
What is angina pectoris?
Sensation of pressure, chest constriction, and pain, commonly one of the first symptoms of CAD
What is the function of the chordae tendineae?
They are fibrous cords that stabilize the option of the AV valves in the heart, preventing backflow during ventricular systole
The heart has two pairs of one-way valves. What do the valves prevent?
The valves prevent the backflow of blood as the chambers contract
The sympathetic and parasympathetic divisions of the autonomic nervous system innervate the heart by means of the nerve network known as?
The cardiac plexus
1. Which side of the heart supplies blood to the systemic circuit?
2. Which side of the heart supplies blood to the pulmonary circuit?
1. Left side (Ventricle)
2. Right side (Ventricle)
What is end-systolic volume?
The amount of blood remaining in each ventricle at the end of ventricular systole
Why does the left ventricle have thicker walls even though it pumps the same amount of blood as the right ventricle?
Because it has to pump blood further
Which law states that the relationship between the amount of ventricular stretching and the contractile force means that, within normal physiological limits, increasing the EDV results in a corresponding increase in the stroke volume?
Frank-Starling Law
What are the two layers of the serous pericardium and their locations?
Parietal layer – located in outer pericardium
Visceral layer - (aka epicardium), located in inner pericardium
What is the function of pericardial fluid and what secretes pericardial fluid?
Pericardial fluid lubricates the serous layers and reduces friction, and is secreted by the serous pericardium into the pericardial cavity
What is another name for the pulmonary valve? Where do you find this valve?
Another name is Pulmonary Semilunar Valve, it is found between the right ventricle and the pulmonary artery
What causes cardiac tamponade?
Excess fluid (pericardial fluid or blood) in the pericardial cavity, which restricts the movement of the heart
1. Where would you find the tricuspid valve?
2. What is another name for the tricuspid valve?
1. The tricuspid valve is located between the right atrium and the right ventricle
2. Another name for the triscuspid valve is the right atrioventricular valve
What is coronary ischemia and what is the usual cause of it?
Coronary ischemia is the reduction in blood flow to the heart muscle that leads to inadequate perfusion and it is caused by coronary artery disease
What occurs during the absolute refractory period?
Cardiac contractile cells cannot generate another action potential because the fast sodium channels are open or inactivated