Studied by 31 PeopleTags & Description
Pulmonary Circuit
Blood flow to the heart then to the lungs then back to heart
Systemic Circuit
Blood flow from the heart to the rest of the body
Artery
A blood vessel that carries blood from the heart to other parts of the body
Conducting Arteries
Large, elastic blood vessels that cushions change in blood pressure
Distribution Arteries
Medium-sized, muscular blood vessels that are often on sites of pressure points
Arteriole
Smallest form of an artery, less muscular with a poor tunica externa; connects to capillary
Capillary
Single cell thick, endothelial blood vessels connecting arterioles with venules; site of gas and nutrient exchange; can be turned on/off
Continuous Capillary
Type of blood vessel that allows water and small molecules to diffuse through - larger molecules/cells do not fit. Completely lined & found in all tissues except epithelia and cartilage
Fenestrated Capillary
This porous blood vessel is seen in the choroid plexus and endocrine organs
Sinusoidal Capillary
Tiny blood vessels like fenestrated, but flatter and more irregular. Occurs in liver, bone marrow, spleen, endocrine organs, intestines, & kidneys
Venule
Smallest form of a vein; connects to capillary
Vein
A blood vessel that carries blood back toward the heart to get oxygenated; has valves to prevent back flow
Tunica Interna
Innermost layer of blood vessels; made of endothilum & internal elastic membrane
Tunica Media
Middle layer of blood vessels; consists of smooth muscle and loose connective tissue; thicker in arterties
Tunica Externa
Outermost layer of blood vessels; made of fibrous connective tissue
Vasoconstriction
Decrease in the diameter of blood vessels
Vasodilation
Increase in the diameter of blood vessels
Atrioventricular Valves
2 valves that allow blood into the ventricles; supported by chordae tendinae
Semilunar Valves
2 valves that allow blood to leave the ventricles into the pulmonary artery & aorta
Parietal Pericardium
The tough outermost layer of the pericardium that is attached to the diaphragm and the sternum
Visceral Pericardium
The innermost layer of the pericardium that adheres to the heart
Epicardium
The outer, serous membrane of the heart wall
Myocardium
The middle, muscular layer of the heart wall
Endocardium
The membrane that lines the cavities of the heart and forms part of the heart valves
Right Atrium
Vena Cavae brings blood to the _____ of the heart
Tricuspid Valve; Right Ventricle
After entering the right atrium, blood passes through the _____ on the way to the _____
Pulmonary Semilunar Valve; Pulmonary Trunk
From the right ventricle, blood is pushed through the _____ into the _____
2 Pulmonary Arteries
From the pulmonary trunk, the _____ takes the blood to the lungs
4 Pulmonary Veins; Left Atrium
Now with fresh oxygen, the _____ returns the blood to the heart's _____
Mitral Valve; Left Ventricle
From the left atrium, the blood has to pass through the _____ to go to the _____
Aortic Semilunar Valve; Aorta
From the left ventricle, blood passes the _____ into the _____, where it is delivered throughout the body
Systemic Arteries
The aorta carries blood to the _____
Systemic Capillaries
The systemic arteries carries blood to the _____ where gas and nutrient exchange occurs
Systemic Veins
The _____ finally returns the blood to vena cavae, where it must pass on the way to the heart
Systole
The contraction of the chambers of the heart to drive blood into the aorta and pulmonary artery
Diastole
The widening of the chambers of the heart between two contractions when the chambers fill with blood
60 - 100 bpm
Normal pulse range
Heart Murmur
An abnormal sound of the heart; usually a sign of abnormal function of the heart valves
Specialized Muscle Cells
Cardiac cells (only 1%) that coordinates the heartbeat
Contractile Cells
Cardiac cells (99%) that propel the blood
Sinoatrial node
Initiates the heartbeat from the upper wall of the right atrium, causes atria to contract, natural pacemaker of the heart
Bundle of His (AV Bundle)
Disperses the signal for ventricular contraction into the right and left bundle branches, then on to the apex and then U-turn into the Purkinje fibers
Electrocardiogram (EKG)
Records electrical impulses from the heart
P wave
Atrial depolarization on an EKG
QRS complex
Ventricle depolarization and atrial repolarization on an EKG
T wave
Ventricular repolarization on an EKG
U wave
Thought to represent repolarization of the papillary muscles or Purkinje fibers on an EKG
An action potential to bring Ca++; binding of Ca++ to troponin
Contractile cells need...
Rapid Depolarization
Step 1 of contraction: Fast Na++ Channels open
Plateau
Step 2 of contraction: Na+ channels close and slow Ca++ channels open and balance +/- ions
Repolarization
Step 3 of contraction: Slow K+ channels opens as Ca++ channels close
Atrial systole > atrial diastole > ventricular systole (1st & 2nd) > ventricular diastole (early & late)
Phases of the cardiac cycle
Cardiodynamics
Movement & force during contractions
End-Diastolic Volume (EDV)
The volume of blood that is in the ventricles before the heart contacts
End-Systolic Volume (ESV)
The volume of blood remaining in the ventricles at the end of a contraction
Cardiac Output
Blood pumped from each ventricle per minute
Epinephrine
A hormone that increases heart rate & stroke volume due to stress
Norepinephrine
A hormone than can increase blood pressure - can also increase heart rate and stroke volume
T3 & T4
Thyroid hormones that regulate how your body uses energy - can increase heart rate and stroke volume
Stroke Volume
Difference between the end-diastolic volume and the end-systolic volume (EDV - ESV)
Preload
How much ventricles can stretch during diastole
Contractility
The amount of force during a contraction per the preload; regulated by ANS, hormones & electrolytes level
Afterload
Amount of tension the contracting ventricle produces to open the semilunar valves
Rheumatic Fever
Reaction to strep infection that deteriorates the valves up to 20+ years later
Pericarditis
Inflamed pericardial surfaces due to friction, increases fluid and causes cardiac tamponade
Coronary Artery Disease
Blockage of coronary circulation, may cause ischemia and angina
Bradycardia
Abnormally slow heartbeat
Tachycardia
Abnormally rapid heartbeat
Premature Atrial Contractions (PACs)
"Surprise" atrial contractions caused by stress, caffeine, and drugs
Paroxysmal Atrial Tachycardia (PAT)
Abrupt episodes of rapid atrial contractions, ventricles can keep pace, HR over 180bpm
Atrial Flutter
Atrial impulses <350 per min., not stable, often degenerates into a fibrillation
Atrial Fibrillation
Impulses up to 500 per minute, atria quiver, ventricles do not keep up, can go unnoticed
Premature Ventricular Contractions (PVCs)
"Surprise" ventricular contractions cause by epinephrine, drugs, and ion imbalances
Ventricular Tachycardia
4 or more PVCs without a normal beat
Ventricular Fibrillation
Ventricles quiver due to an uncoordinated contraction, to the point of no longer pumping; can cause cardiac arrest - can be fatal
Mitral Valve Prolapse
Cardiopathy resulting from the mitral valve not regulating the flow of blood between the left atrium and left ventricle of the heart
Myocardial Infarction
Destruction of heart tissue resulting from obstruction of the blood supply to the heart muscle; heart attack
Capillary Bed
A layer of tissue densely packed with capillaries. Blood travels through metarteriole or on to a thoroughfare channel
Arteriole Anastamosis
Collateral arteries merge and creates a direct connection between an arteriole and a venule
Metarteriole
Link between an arteriole and a venule; serves as a vascular shunt when precapillary sphincters are closed
Thoroughfare Channel
Continuation of metarteriole at venule end that enables blood to bypass capillary bed. Lacks smooth muscle
Hydrostatic Pressure
Created by a force pushing a liquid (blood). Pushes from high to low
Blood Pressure
Arterial pressure
Capillary Hydrostatic Pressure (CHP)
The pressure exerted by blood against the wall of a capillary