Item 10 Flashcards
Chapter 13 (read the sections that relate to the lecture slides)
heart
The _ is a muscular pump that drives the flow of blood through blood vessels, and serves sensory and endocrin functions by regulating blood pressure and volume
heart
_ _ conduits through which the blood flows, and are sensory and effort organs, regulating blood pressure and distribution
blood vessels
_ is fluid that circulates around the body carrying materials to and from the cells with the nervous system, acting as a communication link
blood
The heart beats _ times per minute, approximately
80
The heart has 4 _ or atrium
chambers
The _ occupy the bulk of the heart. The arteries and veins all attach to the base of the heart (located at the top)
ventricles
The right and left _ receive blood and hold onto it before being pumped
atrium/atria
The right and left _ are the pumps of the system
ventricle
The _ ventricle is much larger than the right, because the former has further to pump than the latter
left
Superior vena cava receives blood from …
the body in general
The _ takes blood from the left ventricle into circulation
aorta
The pulmonary artery takes blood from the _ ventricle to provide blood for the lungs
right
The atrialventricular valves (which take place between the atria and the ventricles) are a.k.a. cuspid valves, with the bicuspid valve taking place in the _ AV, and the tricuspid valve taking place in the _ AV
left;
right
- shown on the opposite sides of the diagram, which imagines a heart facing me
Cuspid valves ensure the one-way movement of blood from _ to _
atrium to ventricle
Blood moves through the heart from the…
1. right _
atrium
Blood moves through the heart from the…
1. right atrium
2. _ valve
tricuspid
Blood moves through the heart from the…
1. right atrium
2. tricuspid valve
3. _ ventricle
right
Blood moves through the heart from the…
1. right atrium
2. tricuspid valve
3. right ventricle
4. _ valve
pulmonic
Blood moves through the heart from the…
1. right atrium
2. tricuspid valve
3. right ventricle
4. pulmonic valve
5. pulmonic _
arteries
Blood moves through the heart from the…
1. right atrium
2. tricuspid valve
3. right ventricle
4. pulmonic valve
5. pulmonic arteries
6. pulmonic _
veins
Blood moves through the heart from the…
1. right atrium
2. tricuspid valve
3. right ventricle
4. pulmonic valve
5. pulmonic arteries
6. pulmonic veins
7. _ _
left atrium
Blood moves through the heart from the…
1. right atrium
2. tricuspid valve
3. right ventricle
4. pulmonic valve
5. pulmonic arteries
6. pulmonic veins
7. left atrium
8. _ valve (left AV valve)
mitral
Blood moves through the heart from the…
1. right atrium
2. tricuspid valve
3. right ventricle
4. pulmonic valve
5. pulmonic arteries
6. pulmonic veins
7. left atrium
8. mitral valve (left AV valve)
9. left _
ventricle
Blood moves through the heart from the…
1. right atrium
2. tricuspid valve
3. right ventricle
4. pulmonic valve
5. pulmonic arteries
6. pulmonic veins
7. left atrium
8. mitral valve (left AV valve)
9. left ventricle
10. _ _
aortic valve
Blood moves through the heart from the…
1. right atrium
2. tricuspid valve
3. right ventricle
4. pulmonic valve
5. pulmonic arteries
6. pulmonic veins
7. left atrium
8. mitral valve (left AV valve)
9. left ventricle
10. aortic valve
11. _
aorta
The heart simultaneously pumps to the _ and systemic circuits
pulmonary
The ventricles pump _, enabling an effective and efficient system
simultaneously
In _ capillary beds, O2 moves into the blood and Co2 leaves
pulmonary
In _ capillary beds, O2 leaves the blood and Co2 enters
systemic
Blood first enters the right atrium and enters the right ventricle, which is then pumped into the _ _, removing Co2 and adding O2
pulmonary circuit
Once the blood is oxygenated and removes carbon dioxide through the pulmonary circuit, it re-enters the heart through the left _ and then is pumped using the left _, into the system
atrium;
ventricle
The 4 valves for ensuring one-way flow of blood are the:
1. tricuspid valve
2. pulmonary semilunar valve
3. bicuspid valve
4. _ _ valve
aortic semilunar
The bicuspid valve is a.k.a. _ valve
mitral
_ _ hold the ends of the cusps, and connect them to papillary muscles
chordae tendenae
When the ventricles are relaxed, blood enters the _, pushing the AV valve cusps down into the _, opening the valves
atria;
ventricles
When the ventricles contract, blood presses up against the AV valve cusps, forcing the valves closed. Contraction of the papillary muscles tightens the _ _, preventing the valve cusps from being pushed into the atria
chordae tendenae
Semilunar valves _ when blood rushes past, then when ventricles are relaxed and semilunar valves are _
open;
closed - valves prevent blood wanting to move down from gravity; caught by this, preventing blood going backward, and improving its efficiency
When the ventricle _, blood in the aorta and pulmonary artery presses down against the valve cusps, forcing them to close
relaxes
Damaged mitral valve is a type of _ disease
cardiovascular
Damage to the mitral valve can lead to the heart…, as an indicator of heart failure because when it changes its function, it has to constantly adapt to inefficient function, leading to cardio dysfunction
changing shape
_ can help with calcification of the mitral valve, which otherwise would have inefficient function
drugs
T or F: mitral valves (left AV valve) can be replaced to prevent heart dysfunction
true
Many valve designs exist that enable one-way flow, some of which are purely mechanical, others are _
biological
e.g., pig valves
Electrical activity in the heart starts with the SA node _
depolarizing
The SA and the AV nodes contain _ cells which automatically set the rhythm of the heartbeat
pacemaker
The _ node is autorhythmic; it works at its own pace
SA
The internodal pathway of the heart is through the walls of the _
atria
Electrical activity goes rapidly to the AV node through the walls of the atria, i.e., _ pathways
internodal (between the nodes - from SA to AV)
Depolarization of the SA node spreads QUICKLY/SLOWLY across the atria, and conduction QUICKENS/SLOWS through the AV node, creating a 0.1 second delay before conduction continues
slowly;
slows - it is slow to allow a delay before conduction to happen, otherwise it would be fast
The only electrical connection between the atria and the ventricles is the Bundle of _
His - why it’s a man not a woman is beyond me
Depolarization of the right atrium moves QUICKLY/SLOWLY through a ventricular conducting system to the apex of the heart, namely the Bundle of His
quickly - men like to do things quickly
Electrical activity in the heart starts with:
1. the SA node depolarizing
2. electrical activity going rapidly to the AV node via internodal pathways/atrial walls
3. depolarization spreads more slowly across the atria, with conduction slowing through the AV node, creating a 0.1 second delay
4. depolarization moves rapidly through the ventricular conducting system to the apex of the heart through the Bundle of His
5. depolarization wave spreads upward from the apex, through _ _, the entire wall of the ventricle
Purkinje fibres
Electrical activity in the heart starts with:
1. the SA node depolarizing
2. electrical activity going rapidly to the AV node via internodal pathways/atrial walls
3. depolarization spreads more slowly across the atria, with conduction slowing through the AV node, creating a 0.1 second delay
4. depolarization moves rapidly through the ventricular conducting system to the apex of the heart through the Bundle of His
5. depolarization wave spreads upward from the apex, through Purkinje fibres, along the entire wall of the ventricle
6. …
the entire heart returns tot he resting state, remaining there until another action potential is generated in the SA node
The SA node depolarizes at a wave that is strong enough to dictate the heart rate, usually _ beats per minute
100
The AV node depolarizes AFTER/BEFORE the SA node
after
Once the AV node is activated by the SA node, it goes into a short delay, a _ _, preventing the AV node from initiating its own “extra” beat
refractory period
The SA node has a HIGHER/LOWER beating frequency than the AV node, which overrides the AV node’s beating frequency
higher
The short delay after the AV node is activated, as well as its lower beating frequency enables the SA node to…
govern the actions of the AV node, not the other way around
T or F: it’s possible for one node to beat the heart, although it’s less effective and would not be able to do so indefinitely
true
Cardiac pacemaker cells automatically initiate each cardiac _ (heart muscle cell)
myocyte
That which is initiated by the heart itself is considered _genic, whereas by the nervous system is _genic
myogenic;
neurogenic
Heart muscle cells can depolarize on their own, therefore they have _
autorhythmicity
The pacemaker cell is really the _-type cell, whereas the cardiac myocyte is the _-type cell
electric;
contract
Pacemaker cells are communicated to cardiac myocytes through _ cells
conducting
T or F: pacemaker cells and cardiac myocytes have the same type of action potential
false - they both can do action potentials, but they’re different/location specific
… have a ver long low phase and then a later action potential
cardiomyocytes
Pacemaker action potentials are UN/STEADY; they fire at threshold which is roughly -_mV (goes up to roughly +20 m’V) and going back to normal is when they return to -_mV
unsteady;
-40 mV;
-60 mV
Pacemaker cells action potentials occur with:
1. ‘funny’ leak channels open allowing_ in, across membrane
Na+
Pacemaker cells action potentials occur with:
1. ‘funny’ leak channels open allowing Na+ in, across membrane
2. some _ channels open, ‘funny’ leak channels close
Ca2+
Pacemaker cells action potentials occur with:
1. ‘funny’ leak channels open allowing Na+ in, across membrane
2. some Ca2+ channels open, ‘funny’ leak channels close
3. action potential starts, with lots of _ channels opening
Ca2+
Pacemaker cells action potentials occur with:
1. ‘funny’ leak channels open allowing Na+ in, across membrane
2. some Ca2+ channels open, ‘funny’ leak channels close
3. action potential starts, with lots of Ca2+ channels opening
4. at its apex, the Ca2+ channels open, _ channels open
K+
Pacemaker cells action potentials occur with:
1. ‘funny’ leak channels open allowing Na+ in, across membrane
2. some Ca2+ channels open, ‘funny’ leak channels close
3. action potential starts, with lots of Ca2+ channels opening
4. at its apex, the Ca2+ channels open, K+ channels open
5. near -_mV, K+ channels close
-60 mV
Pacemaker cells action potentials occur with:
1. ‘funny’ leak channels open allowing Na+ in, across membrane
2. some Ca2+ channels open, ‘funny’ leak channels close
3. action potential starts, with lots of Ca2+ channels opening
4. at its apex, the Ca2+ channels open, K+ channels open
5. near -60 mV K+ channels close
6. funny channels _ until an action potential may start
open
_ stimulation with SA node pacemaker activity would create more rapid depolarization, stimulating more action potentials by changing funny channels by opening faster, allowing more Na+ influx, and therefore a steeper depolarization
sympathetic - fight-or-flight
- more beats per minute, due to increase in funny channels
_ stimulation with SA node pacemaker activity involves later closing of the funny channel, less Na+ influx, and shallow depolarization.
Also, there is longer opening of K+ channels causing greater K+ efflux (hyperpolarized)
parasympathetic - rest and digest