The Heart And Circulatory System Flashcards
Define Plasma
an aqueous solution of proteins, ions, nutrient molecules and gas but mostly water
Define erythrocytes(rbc)
Are the oxygen carriers of the blood
Define Leukocytes(wbc)
-provide the body’s front line of defense against disease
Define Platelets
-induce blood clots that seal breaks in the circulatory system
Bone marrow has multipotent stem cells that give rise to:
-Myeloid stem cells and lymphoid stem cells
What type of cells come from myeloid stem cells
-erythrocyte, platelets, monocyte/macrophage, eosinophil, basophil, neutrophil
What type of cells come from lymphoid stem cells
Natural killer cell, T lymphocyte, B lymphocyte
What are the three plasma proteins
-Albumins
-globulins
-fibrinogen
What plasma protein is responsible for osmotic balance, pH, transport, hormones, waste, and drugs
-Albumins
What plasma protein is responsible for transport of lipids, fat soluble vitamins
-Globulins (ex. immunoglobulin)
What plasma protein is responsible for blood clotting
-Fibrinogen
What are the plasma ions
-Na+, K+, Ca2+, Cl-, HCO3-
What are the functions of erythrocytes
Contain hemoglobin (transports oxygen to lungs), flexible can squeeze through capillaries
What are the functions of Leukocytes
Defend body against infecting pathogens, eliminate dead and dying cells
What are the functions of platelets
-cell fragments enclosed in plasma membrane, triggers clotting
What are the four chambers of the heart
-Two atria at the top of the heart
-Two ventricles at the bottom of the heart
-Atrioventricular (AV) valves between atria and ventricles
-Semilunar (SL) valves between ventricles and aorta/ pulmonary arteries
What are the two separate circuits the blood is pumped into
-Pulmonary circuit
-Systemic circuit
What are the systole and diastole in the basic heart beat
-Systole: ventricle contracting
-Diastole: ventricle relaxing, chambers filling, atria relaxing
Pulmonary artery pumps
-deoxgenated blood in the lungs
Pulmonary vein pumps
oxygenated blood into the heart
Systole-diastole sequence is the
-cardiac cycle
Systolic pressure
-contraction of ventricles pushes blood into arteries at peak pressure
Diastolic pressure
-between ventricular contractions, blood pressure in arteries falls to a minimum pressure
Define afterload
systemic vascular resistance, is the amount of resistance the heart must overcome to open the aortic semilunar valve and push the blood volume out into the systemic circulation
Define preload
-left ventricular end diastolic pressure is the amount of ventricular stretch at the end of diastole. The heart is loading up for the next big squeeze of the ventricles during systole
What are the steps of the cardiac cycle
-heart is fully relaxed; atria begins to fill with blood; AV and SL valves are closed
-blood fills atria and pushes AV valves open; ventricles begin to fill
-atria contract, filling ventricles completely
-ventricles begin to contract, forcing AV valves closed; SL valves remain closed
-Ventricles contract fully, forcing SL valves open and ejecting blood into arteries
Define stroke volume
-the amount of blood ejected per beat from left ventricle and measured in mL/beat
-Stroke volume increases proportionally with exercise intensity
SV= EDV-ESV
-stroke volume equals end diastolic volume(volume of blood in ventricle after filling phase)- end systolic volume(blood left in the ventricle after contraction)
Define cardiac output
the amount of blood pumped by the heart in 1 minute measures in L/min
-if either heart rate or stroke volume increase or both, cardiac out increases also
What is the main idea of stroke volume-force of contraction
-Amount of blood pumped out is proportional to how much blood returns to the heart
-As more blood comes back to the heart, the blood that is coming back stretches the heart muscle to a great extent than normal
If more blood comes back…
the heart muscle is stretched more and the volume leaving per beat is increased
What other two things can effect the force of contraction?
-Sympathetic and parasympathetic activity
How does the parasympathetic nerve stimulation effect the heart rate
-it decreases the heart rate
What do parasympathetic neurons produce
-the neurotransmitter, Acetylcholine
How does acetylcholine effect the heart rate
-ACh binds to ligand gated channels on the cardiac cell membrane which causes K+ to go out which hyperpolarizes the cell. The hyperpolarized membrane take longer to depolarize and causes and action potential
-the heart rate decreases
How do M2 muscarinic receptors effect the heart rate?
-they act to slow the heart rate down to normal sinus rhythm after stimulatory actions of the sympathetic nervous system, by slowing the speed of depolarization
Where are the sympathetic nerves located that send signals to the heart?
-The thoracic region of spinal cord project to the heart as cardiac nerves
Sympathetic nerves innervate the….
-SA and AV nodes
-the coronary vessels
-the atrial and ventricular myocardium (heart muscle)
Does sympathetic stimulation increase or decrease heart rate and force of muscular contraction?
-increase
Sensory neurons carry action potentials from… Chemoreceptors in the medulla oblongata influence the…
-baroreceptors to the cardioregulatory center.
-cardioregulatory center
The cardioregulatory center controls…
-the frequency of action potentials in the sympathetic and parasympathetic neurons
Parasympathetic neurons extend to the
-heart through the vagus nerves
Sympathetic neurons extend through…
-the adrenal medulla
Sympathetic neurons increase the section of …
-epinephrine and some norepinephrine into the general circulation
Epinephrine and norepinephrine increase/decrease the heart rate and stroke volume
-increase
What is norepinephrine and epinephrine classified as
-catecholamines
Definition of catecholamines
-An amine derived from the amino acid tyrosine, act as hormones or neurotransmitters
How does norepinephrine increase the rate and degree of cardiac muscle depolarization which causes an increase in the frequency of the action potential and the force and velocity of the contraction
norepinephrine is an agonist for cell surface beta adrenergic receptors. This causes G-protein mediated synthesis and accumulation of cAMP in cardiac cells. This opens Ca2+ slow channels, increasing the cell’s ability to depolarize. Also helps open sodium channels.
Epinephrine(adrenaline) is a hormone released from…
-the adrenal medulla
Increased physical activity, emotional excitement or stressful situations causes…
-sympathetic stimulation of the cardio-regulatory center in the brainstem(medulla)
Epi and Norepi are transported through the blood to the cardiac muscle cells where they bind to
beta andrenergic receptors
What are the two major effects of Epi and Norepi
-Epi and norepi prepare the body for fight or flight
-they increase blood pressure and heart rate and up regulate the blood and oxygen supply to muscle tissue
What is the sympathetic neurotransmitter: Norepinephrine and hormone epinephrine affect:
-the channels that bring calcium into the cell
-the channels that allow calcium to leave the sarcoplasmic reticulum
-the calcium troponin interaction
-the reuptake of calcium into the sarcoplasmic reticulum
If the interaction between the troponin and the calcium is faster the heart…
-contract faster
If calcium is taken up by sarcoplasmic reticulum faster the heart…
-relaxes faster
Neurogenic hearts (in some crustaceans)….
-beat under control of nervous system
Myogenic hearts (all other animals besides some crustaceans) contractions initiated…
-within the heart
-the nerves going to the heart only regulate the rate of the heart beat
Define auto-rhythmic
heart stimulates itself to contract at regular intervals
-uses pacemaker cells(excitable cells) in SA node to generate action potentials spontaneously and at regular intervals
Pacemaker cells have a …. Membrane that allows….. To cross
pacemaker cells have a specialized cell membrane that allows Na+, K+ and Ca2+ to cross and trigger their electrical impulses
Contraction of cardiomyocytes requires….
-depolarization and repolarization of their cell membranes
-movement of ions across cell membranes causes this depolarization and repolarization
-signals are initiated from the sinoatrial node
The only way to get from the atria to the ventricle is through
-some conducting fibers that have small diameters
Summarize conduction through the heart
-signals from SA node spread through the atria
-signals are delayed at AV node
-bundle branches pass signals to heart apex
-signals spread throughout ventricles
Define electrocardiogram
-A measure of electrical activity that can be measured at the surface of your body
Describe arteries and their actions
Carry blood away from the heart
-thick walled to withstand high pressure
-large diameters, low resistance to flow
-are stretches when blood flows from the heart
Describe capillaries and their actions
-Are the site of exchange
-thinnest walls
What are precapillary sphincters
they are a band of smooth muscles that adjusts the blood flow into each capillary. Contraction of the precapillary sphincter can close the branches off to blood flow.
The rate of blood flow is slower in… than in.. and … because
the rate of blood flow is slower in capillaries than in arteries and veins because it maximizes time for exchange of substances between blood and tissues
What are the two major mechanisms drive exchange of substances
-diffusion along concentration gradients
-bulk flow
In the context of capillary cross section, water soluble substances diffuse through..
intercellular clefts(between endothelial cells 1 and 2) and through fused vesicle channels
Whether fluid will move out of or into a capillary depends on:
-net filtration pressure: equals the hydrostatic pressure of the blood in the capillaries minus the hydrostatic pressure of the blood in the capillaries minus the hydrostatic pressure of tissue fluid outside the capillaries
-oncotic pressure
In the context of fluid between capillaries and tissues: Concentrations of solutes are generally … in tissue and plasma
-are generally the same
In the context of fluid between capillaries and tissues: protein concentration of plasma is… than protein concentration of interstitial fluid
-greater than
Define colloid osmotic pressure:
-osmotic pressure exerted by plasma proteins such albumin
The lymphatic system collects…
-excess interstitial fluid, transports it to lymph ducts that empty into veins
Describe the lymphatic system
-key component of the immune system
-extensive network of vessels
-lymphoid tissues and organs act as filters and participate in the immune response
What are the tissues and organs of the lymphatic system
-lymph nodes, spleen, thymus, tonsils
-remove viruses, bacteria, damaged cells, and cellular debris from lymph and bloodstream
-defend the body against infection and cancer
Blood moves through veins in response to
-Relatively high pressure in the veins caused by blood leaving the capillaries
-contraction of smooth muscle in the walls of the veins
-contraction of the valves in the veins
-contraction of skeletal muscles surrounding the veins
-contraction of smooth muscle in the walls of the veins
-contraction of skeletal muscles surrounding the veins
Describe veins and its function
-veins have thinner walls than arteries
-veins act as blood reservoirs as well as conduits
-pressure from movements of skeletal muscles help return blood to heart
-one-way valves prevent blood from flowing backward
Autonomic nervous system and endocrine system interact to coordinate these mechanisms
-nitric oxide is a major inducer of vasodilation
-endothelin is a peptide and major inducer of vasoconstriction
Which ion permeability is the first to change in the SA node when generating a beat?
-calcium with L channels
-sodium
-potassium
-calcium with T channels
Potassium
The Berlin heart is a machine used to treat heart failure by helping the heart pump oxygenated blood to the rest of the body. What parts of the heart might this machine attach to?
A) left ventricle and left atrium
B) left ventricle and aorta
C) right ventricle and right atrium
D) left atrium and right ventricle
E) right atrium and left ventricle
B) left ventricle and aorta
The semilunar valves prevent blood form flowing backwards
A) into the atria
B) into the ventricles
C) into the brain
D) into the liver
E) into the lungs
B) into the ventricles
The term systole and diastole refer to
A) sounds from the heart
B) the major artery and vein from and to the heart
C) heart contractions and relaxation
D) rate of heart pulse
C) heart contractions and relaxation
The arteries that directly feed unto the capillary beds are called
A) muscular arteries
B) elastic arteries
C) arterioles
D) venues
E) capillaries
C) arterioles
The brain controls the heart rate by sending neural messages to the sinoatrial node which is located in the
A) right atrium
B) left atrium
C) right ventricle
D) left ventricle
A) right atrium
Which of these are not a type of blood cell?
A) myocytes
B) leukocytes
C) erythrocytes
D) thrombocytes
E) all of these are blood cells
A) myocytes
Which artery carries deoxygenated blood in the body?
A) aorta
B) pulmonary artery
C) inferior artery
D) superior artery
B) pulmonary artery
In the capillary blood vessels, an exchange of gases takes place with cells. Which of the following is the correct gas exchange ?
A) oxygen leaves the capillary to the cell, and carbon dioxide enters the capillary
B) carbon dioxide leaves the capillary to the alveolus and oxygen enters the capillary
C) nitrogen leaves the capillary to the cell, and carbon dioxide enters the capillary
D) oxygen leaves the capillary to the cell, and nitrogen enters the capillary
A) oxygen leaves the capillary to the cell, and carbon dioxide enters the capillary
The pale yellow liquid in the blood is called …..
A) platelets
B) plasma
C) lumen
D) glucose
B) plasma
All arteries of the body flow
A) to liver
B) to brain
C) away from lungs
D) away from heart
D) from the brain
D) away from heart
True or false
The concentration of solutes is slightly greater in the interstitial fluid than in the blood
False. The concentration of solutes in interstitial fluid is equal to their concentration in blood because solutes can filter through capillary pores
True or false
The concentration of proteins in the interstitial fluid is less than blood
True . The concentration of proteins in the blood is greater than in the interstitial fluid because protein filtration is limited through capillary pores
True or false
The colloid osmotic pressure is greater in the blood than in interstitial fluid
True
The direction substances move (into or out of the capillary) depends on ….and …these are called …forces
Net filtration pressure
Oncotic pressure
Starling forces
Which of the following is not an organ involved in the lymphatic system?
A) spleen
B) thyroid gland
C) lymph nodes
D) thymus
E) tonsils
B) thyroid gland
Nitric oxide released by arterial endothelial cells
A) decreases arteriole diameter
B) increase arteriole diameter
C) decreases blood flow
D) increases blood flow
E) both b and d
E) both b and d
Smoking cigarettes can damage which part of the lung?
A) alveoli
B) bronchioles
C) bronchi
D) pleural cavity
E) all of the above
E) all of the above
Which of the following conditions can be treated with a pacemaker device ?
A) afib
B) ventricular tachycardia
C) sinus node dysfunction
D) myocardial infarction
E) premature ventricular contraction
C) sinus node dysfunction
Which of the following is a potential consequence of a pulmonary embolism ?
A) asthma
B) pneumonia
C) popcorn lung
D) hypoxia
E) high blood pressure
D) hypoxia ( low oxygen levels )
A patient with a high amplitude of their QRS complex might have?
A) thickening of left ventricular wall
B) mitral valve prolapse
C) atria dilation
D) myocardial infarction
E) sinus tachycardia
A) thickening of left ventricular wall
Plasma and plasma proteins contain
water,ions, dissolved gases (O2 and CO2) glucose, amino acids, lipids, vitamins, hormones and plasma proteins
What are the plasma ions
Na+, K+, CA2+, Cl-, HCO3-
Parasympathetic nerve stimulation has an… effect which
inhibitory, decreases heart rate
the …nerve carries parasympathetic nerve fibers to the heart (primarily)
vagus nerve
Vagus nerve innervates the
SA node(cluster of cells in the right atria that generate electrical impulses that initiate the heartbeat. Is the heart’s pacemaker)
arterioles
(small branches of arteries) deliver blood to capillaries
-constrict and dilate, regulate flow and pressure of blood into capillaries
capillaries
exchange material with interstitial fluid
venules
collect blood from capillaries
