Say it to get the mark, what gases are being transported? - ANSWER co2
from tissues to lungs
o2 from lungs to tissues
movement of gas is based on what?
what type of movement? - ANSWER bulk movement from high to low
pressure.
via diffusion
what is tidal volume? - ANSWER volume of air moved into and out of lungs
during each ventilation cycle
what are 4 examples of properties that respiratory and circulatory systems
contain to facilitate gas diffusion - ANSWER large surface area for gas
exchange
large partial pressure gradients
gases w advantageous diffusion properties
specialised mechanisms for transporting O2 and CO2 bt lungs and tissues
explain partial pressure - ANSWER sum of partial pressures of a gas equal
total pressure.
partial pressure of gas=fraction of gas (fgas) in gas mixture x barometric
,pressure
so what is the partial pressure of oxygen? - ANSWER 21% o2 in the air
po2=0.21 x 760mmHg
=159mmHg
what happens in the airways to air? - ANSWER warmed and humidified,
saturated with water vapour.
skip to the heart.
the mitral valve (bicuspid) is on what side? - ANSWER LEFT! atrioventricular
the semilunar valves of the heart are what?
where? - ANSWER outflow- pulmonary valve of p. artery and aortic valve of
aorta.
bt ventricles and those vessels
explain isovolumetric contraction of the ventricles of the heart - ANSWER
interval bt closing of AV valves and opening of semilunar valves. *all valves
closed so no change in volume*
When does isovolumetric contraction take place? - ANSWER During QRS
after closure of mitral valve but before the aortic valve opens
early ventricular systole.
equation for cardiac output - ANSWER CO = HR x SV
equation for blood pressure - ANSWER BP = CO x PVR
the layers of heart tissue in the heart include the endocardium, myocardium
,(cardiac muscle), epicardium, pericardial cavity and parietal pericardium, with
a dense fibrous outer layer.
what do the endocardium, epicardium and parietal epi contain? - ANSWER
areolar tissue (loose connective collagen) and endothelium or epithelium
Which ventricle has a thicker wall? - ANSWER left
what is the resting membrane potential of the heart?
depolarisation vs repolarisation charges - ANSWER -80mV
depol= less (-) inside
repol= more (-) inside
currents of what ions in what direction are depolarising for the heart? -
ANSWER na and ca inwards.
currents of what ions in what direction are repolarising? - ANSWER k
outwards
k and na, where are they greater inside or outside of cell? - ANSWER K+
greater inside
Na+ outside
action potential is basically sequential activation and inactivation of inward
ca and na and outward k currents
at the resting potential, what is the relationship bt electrical and
concentration gradients? - ANSWER they are equal
so during an action potential, there is depolarisation. explain why - ANSWER
opening of VGSCs, allow inward Na+ so positive influx, inside becomes less
, negative.
what is phase 0 of the AP? - ANSWER the opening of VGSCs and influx of Na
what is phase 1 (notch) of AP? - ANSWER repolarisation- K+ leaves, so inside
becomes more - again.
inactivation of VGSC
next phase of AP? - ANSWER plateau phase 2.
balance of inward Ca2+ and outward K+.
so depol=repol
what is phase 3 of the AP? - ANSWER repolarisation, inward currents
inactivated and outward K+ predominate.
more - inside
final phase of AP - ANSWER resting -80mV
what APs mediate normal rhythm? (7)
combine their profiles to get what? - ANSWER specialised APs- SAN, atrial
muscle, AVN, common bundle, bundle branches and Purkinje fibres,
ventricular muscle
PQRSTU wave
there is a hierarchy of pacemakers. explain giving the bpm rates for three
main
in a normal healthy heart, which will predominate? - ANSWER SAN 70bpm
AVN 50bpm
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller Newsolution. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $14.99. You're not tied to anything after your purchase.