Exam 3 Lecture Notes Flashcards
heart depolarizes and contracts completely on its own
achieved via …: holes made of proteins called … which form portal between adjacent cells
allows for spreading of …
gap junctions; connexins; change in voltage
overall contraction of heart is similar to those in …:
action potentials
important to have more than … heartbeats per second because of the long …
skeletal muscle;
4;
absolute refractory period
heart has same basic overall architecture as in skeletal muscle:
…, resting membrane potential in cardiac muscle is a little lower than in neurons (… mV) but is still depolarized to … mV
the fact that calcium channels stay open longer means that the cell can take longer to …
fast sodium gated channels;
-90;
30;
reset for another contraction
for the heart, there is … for depolarization (not actually a … rise)
very few ms; vertical
the plateau of the action potential is not a
completely flat region
total length of action potential is longer as is the contractile phase:
must wait for … to inactivate and for … to open– won’t open for at least … ms
slow calcium channels;
very slow voltage gated K+ channels;
100
at least … longer delay for K+ channels in cardiac muscle as compared to neurons
100x
… cells that allow for automated contractility have … channels that never …
autorhythmic; slow sodium; fully close
autorhythmicity referred to as …
pacemaker
slow sodium channels allow sodium to leak into cell constantly and one it reaches threshold, … open, yielding rising phase of action potential
calcium channels
unlike every other action potential trace we’ve seen, there’s no … at resting membrane potential because we’re always … into these cells
“resting”; leaking some sodium
these slow sodium channels are much more numerous and are open in large enough numbers to allow the pacemaker cells to hit threshold all the time
… reach threshold
gradually
depolarization here is primarily due to … rather than sodium
repolarization again due to …, but there’s no undershoot because by the time repolarization is complete, some … are open again
influx of calcium;
K+ efflux;
slow sodium channels
different cell types have different rhythms:
channels only differ in … among pacemaker cells but overall mechanism is the same
how long they’re open/closed
(pacemakers of the heart) SA node: in … – mostly concerned with contraction of …
right atrium;
atria
(pacemakers of the heart) SA node:
… for the heart - sets … for the rest of the pacemaking cells within the heart
major pacemaker; rhythm;
(pacemakers of the heart)
SA node:
capable of … – about … timex/min –> falls into normal range for heartbeat
… pacemaker cell in the heart
contracting spontaneously; 75;
fastest
(pacemakers of the heart) AV node:
located just underneath groove that separates … from … - primarily concerned with contracting …
atria;
ventricles;
ventricles
(pacemakers of the heart) AV node:
smaller than SA node
takes longer to spread rhythmic signal due to the fact that there are …
receives direct input from …
fewer gap junctions;
SA node
(pacemakers of the heart)
AV node:
When SA node fires action potential directly on AV node, it doesn’t do anything for about tenth of second - delay is such that atria can be … enough that most of the blood has been squeezed into … before the ventricles contract
squeezed closed enough;
ventricles
(pacemakers of the heart)
AV node:
depolarization rate is about …% slower than SA node
50;
(pacemakers of the heart)
AV node:
damage to SA node will not necessarily result in death because … will take over
extreme damage to SA will ensure that without implantation of pacemaker, .. beats/min not typically sufficient for people, so individuals will be winded just from low intensity exertion like walking
AV node;
50
(pacemakers of the heart)
larger … per heartbeat in those that are physically fit which is why lower heartbeat occurs in athletes
cardiac output
(pacemakers of the heart) Atrioventricular bundle (...): no ... at border between atria and ventricles because we want that .. s delay between SA and AV firing so we don't want these electrically coupled, otherwise, contraction would occur in the entire heart at the same time
bundle of His;
gap junctions;
0.1
(pacemakers of the heart) right and left bundle branches:
carry electrical signals through … to … and then back up towards top of each …
branch into …
interventricular septum;
apex;
ventricle;
purkinje fibers
(pacemakers of the heart)
purkinje fibers:
these are what go from … up to …
… but extremely slow
apex; ventricular wall;
autorhythmic
(pacemakers of the heart) arrhythmia may be result of … to heart, …, or just naturally occurring:
can run in families
typically not life threatening
damage; infection
(pacemakers of the heart)… in bundle of His or AV bundle itself such that atrial and ventricular contractions aren’t coupled normally
disturbances
(pacemakers of the heart) …: heart loses ability to coordinate regular contractions and heart flutters such that there is no … - not ejecting any blood out of the heart
fibrillation; ‘
full contraction
(pacemakers of the heart)
almost no SA innervation reaches AV when AV node is damaged and so relying almost completely on … which can’t sustain sufficient rate - more harmful than SA node damage
… not contracting enough to keep you alive
branches; ventricles
(pacemakers of the heart) opening to atria are only places in heart where there are no …
heart valves
cardioacceleratory innervate both … and … itself - allows contraction to be more forceful:
innervates … as well
each beat ejection more …/beat
pacemaker cells; heart tissue;
coronary arteries;
fluid
cardioinhibitory center only innervates …, not heart muscle because you can’t tell hear to contract less forcefully:
… bypasses spinal column itself and directly innervates
pacemakers;
vagus nerve
heart beat trace gives us direct information about how well different areas of the heart are … and … with one another
electrically coupled;
coordinated
P wave: initial … in cardiac cycle - when … node fires
small plateau in … interval: where delay occurs between AV and SA firing
depolarization;
SA;
P-Q;
ventricular contraction when AV node fires indicated by …
buried in there is another wave when … occurs - if heart is working properly you never see this
QRS complex;
repolarization
… wave is for ventricular repolarization
T
another flat line in heart trace when … and then cycle begins again
fully repolarized
can dissect altered ECG to obtain information about what tissue has been … in the patient
damaged
no P waves in … because no wave of depolarization is spreading across atria
junctional rhythm
2nd degree heart block: … is damaged, small … - some atrial contraction, some ventricular contraction, but they aren’t … with one another – EKG where essentially getting … atrial contractions/ventricular contractions:
2 …/..
AV node; QRS complexes; coordinating; 2; 2 P waves/QRS wave
those struck by lightning experience the following as far as 60 mins after the strike:
ventricular fibrillation: wild fluctuation in …, waves …
contraction intensity; closely spaced together
defibrillator only … does not start new …
stops fibrillation; heartbeat
restart heart by … stimulating and giving dose of …;
mechanically; adrenaline
heart murmurs developed later in life is typically due to … (e.g. scarlet fever- protein outside of this pathogen that resembles protein on heart valve - … - immune system attacks heart valves after infection)
heart no longer functioning as efficient mechanical pump
infection;
molecular mimicry
direction of sound waves coming from each of the … is where stethoscope is placed when listening to heart sounds
heart valves
when AV valves are open attracting force of … pulls fluid into ventricles - due to … force as well
no .. present in circulatory system
this is why you can survive with SA node damage
H-bonding;
vacuum force;
air
beta blockers block … receptors
beta 1 adrenergic
hypertension increases pressure ventricles have to exert to overcome pressure in
SL valves
…factors are the hormones that regulate heartbeat
chronotropic
acetylcholine is a … chronotropic factor:
K+ efflux makes it … for heart to contract which … heart rate
negative;
harder;’
decreases
larger than average amount of blood flowing into atria (e.g. when you spontaneously jump up from seated position) –> increase … in SA node –> activate … and … heart rate
Heart “assumes” there’s a reason as to why you jumped up
stretch;
atrial reflex;
increases
thyroxine has … effect with norepi and epi - this is why thyroxine is main … hormone
increasing basal metabolic rate by …
synergistic;
metabolic;
increasing heartrate
generally around … bpm or less typically not adequate for maintaining consciousness
50
… can be indicative of problem with heart’s conduction system/dampening of … center
bradycardia; cardioacceleratory
CHF: over course of number of years, heart is weakened to the point that it can’t … forcefully enough to maintain adequate circulation:
typically due to persistent … which is why this condition is considered silent killer
baroreceptors don’t know this- they only respond to momentary changes in pressure
contract;
high blood pressure
don’t want heart to be … than its supposed to be - heart pushes up against the rest of thorax and can’t expand as much as it needs to such that it must contract even more forcefully –> over time … heart and it eventually dies
larger;
weakens
…: looking for fatty deposits, if they’re too occluded, they will do open heart surgery and will take veins from … and use them for the heart
stent is less invasive –. goes through … artery instead of doing open heart surgery
many stents coated with drugs that prevent further fat deposits - these drugs last a long time
coronary bypass;
legs
femoral artery;
…: site of gas exchange
alveoli
beginning of respiratory system starts at the …:
system has only one proper exit and entrance, the mouth isn’t intended for respiration, it’s mostly concerned with digestion
… lead into nasal cavity
nose;
nostrils
lungs sit in …, and are superior to the …
pleura; diaphragm
respiratory zone is where … occurs
actual diffusion of gases
changes in volume of chest are what allow for … of air –> due to … movement (mainly diaphragm, but intercostal muscles are involved in that they change … of the chest as one breathes)
physical movement;
muscle;
elasticity
nose’s primary job is to act as opening for gas to enter:
nasal passages are covered in …
tons of .. in nasal cavity because the nasal passages are actually responsible for not only … the air, but … cold air that comes into respiratory system. otherwise, there would a risk of, if inhaling cold air, freezing/partially freezing and damaging lung tissue with each breath
mucus;
blood vessels;
moistening;
warming;
nose has … to filter and clean air
nasal cavity is responsible for … in voice, this is why having a stuffy nose changes what your voice sounds like
nose hairs;
resonation
…: soft tissue that vibrates in the back of nasal cavity
… is physical vibration of this tissue
soft palate;
snorting
…: lumen of the nasal cavity
vestibule
…: mucosal tissue that lines everything all the way back to the very back of the nasal cavity
loaded with …, secretes …
olfactory mucosa;
capillaries;
mucus
epithelial cells of respiratory mucosa warm and moisten air and also secrete … materials called … and … –> lyse bacteria open
part of the … immune system, that provide immunity against things that enter the body with every breath
antimicrobial;
lysozyme; defensins;
innate
epithelial cells of respiratory mucosa are … –> protrusions that beat in one direction (toward the …) to secrete mucus in that direction
ciliated;
back of the throat
when too much “stuff” has accumulated in the nose, … is triggered
cilia are no longer able to …, they sense that and trigger a sneeze
sneezing;
beat mucus backward
reclaiming … with each exhalation –> the conchae are so convoluted, so that when air passes out of the nose and over those little folds, some of the … is reclaimed
reclaiming body heat;
heat
the small amount of time the air spends in lungs, it gets a little … than blood vessels in nose (heat travels from regions of … temp to regions of … temp, which is why reclamation of heat can occur)
hotter;
higher;
lower ;
…: all nose, nasal cavity
nasopharynx
…: now both food and air are present
… distributed around area of palatine tonsils, to provide protection against pathogens
oropharynx;
WBC
…: where larynx meets the pharynx
laryngopharynx
olfactory receptors only occupy a very … in nasal cavity
small space
trachea provides an area of … structure that is difficult to … to continuously allow air to go to lungs
has …
hard; ‘
collapse ;
cartilaginous rings
voice is produced in …
larynx
… sits in Adam’s apple
thyroid gland
laryngeal prominence (adam’s apple) is present in any human being that has a large amount of … in blood for an extended period of time
free flowing testosterone
proper name for vocal cords are …
vocal folds … when air is passed over them to produce sound
vocal folds;
vibrate
more … than actual … folds
vestibular folds; vocal
… and … vocal cords = higher pitch of voice
… and not as … = lower pitch of voice
shorter; tighter;
longer; nost as tight
different resonances determined by
various chambers in head
vocal folds act as … to close glottis
muscular sphincter
valsalva’s maneuver occurs unconsciously when … or when you’re …
emptying bowels; upside down
trachea is the … to the lungs proper
physical conducting zone
cartilaginous rings of trachea are not …, shaped like C, … connect the posterior parts of them
fully closed;
trachealis muscles
contraction of trachealis muscle forces air through it faster –
coughing
…: has elaborate shape that allows the two branches to go to each of the lungs
carina
trachea now sweeps mucous … (the job is to get mucus …)
up; out of the lungs
…: where all the “stuff” enters the lungs
bronchial tubes, nerves, lymph, etc
hilum
left side of lungs has to accomodate space of .. and thus has fewer lobes and fewer branches
heart
right bronchus is more … with trachea than the left bronchus and is thus more susceptible to …/…
vertical;
lodging; blockages
… connect each one of the alveoli in alveolar sac –> ensure that alveolar sac can still … and participate in gas exchange even if one of the pores/alveoli is occluded
alveolar pores;
inflate;
most of alveolar sac is … –> lungs have very large … but very small … –> need it to be mostly empty, so you can get as much air as possible when breathing
empty space;
volume;
mass
breathing in entails contraction of various muscles:
thoracic volume … and pulls on tissue of lungs themselves
pleura is being … and lungs stretch, increasing intrapulmonary volume, creating momentary negative intrapulmonary pressure
air flows into lungs to try to … pressure
increases;
pulled apart;
equalize
forced expiration is an active process that uses
abdominal muscles
…: resistance of flow of air in and out of the lungs
airway resistance
….: surface tension of the fluid that’s actually on the alveoli
alveolar surface tension
…: how stretchy/elastic the lungs actually are
lung compliance
high … allows for air to flow without being impeded
cross sectional area
alveoli have to be …, otherwise efficient diffusion won’t occur
wet
if alveoli is just wet with water, water is so “sticky” that high surface tension will cause alveoli to …
collapse
surfactant: soapy substance (it’s a lipid), has a .. and … portion, this is mixed with… in the lungs
polar; nonpolar; water
surfactant:
detergents inhibit .. and prevent surface tension of water
water is thus less … and there’s less pressure and force pulling the alveoli towards one another
H bonding
cohesive
surfactant is produced by … cells
type II alveolar
premature babies that come about … weeks early have yet to produce … cells to produce enough surfactant- must be put in an incubator that provides surfactant to the baby until the lungs are developed enough to produce surfactant on its own
6;
type II alveolar
fibrosis is caused by …, …, or exposure to certain … (such as cement dust, asbestos)
smoking; air pollution;
environmental toxins
lung compliance is either reduced due to some … or it’s …
genetic component; environmental
decreased flexibility of thoracic cage is caused by inability to expand thoracic cage on your own because of …
weight