Heart Flashcards
Why is the left bigger than the right?
Right needs to pump at a lower pressure so it doesn’t damage the delicate capillaries In the lungs. There isn’t enough space in the journey from the heart to the lungs for the branching required to lower the pressure.
What do stents do?
Stents straighten out veins and arteries to protect them.
What type of hearts do fish have
Single pump, there is little respiration in the heart as fish have little blood.
What type of heart do we have?
Double pump, heart then lungs then heart then body. As more respiration as more active. Quicker blood means more O2 and quicker ror.
Amphibians have what type of heart?
Mix of two! They have 2 atria but 1 ventricle. This shows the evolutionary process from fish to mammals.
What are insects hearts like?
They have no heart! It is an open space! This is fine if they are small but if they get larger this becomes difficult to maintain the conc. gradient.
What does lup dup mean?
Lup= atrioventricular valves closing Dup= semilunar valves closing
What does ventricular systole mean?
Ventricles contracting
What does atrial diastole mean?
Atriums relaxing
What happens in lup?
Ventricular systole and atrial diastole.
What does ventricular diastole mean?
Ventricles relaxing
What does atrial systole mean?
Atriums contracting.
What happens in dup?
Ventricular diastole and atrial systole.
How does pressure regulate valves?
Low pressure sucks the valve up, and high pressure below keeps pressure holding it closed making an airtight seal. When this is reversed the valve is opened.
What does the dif. Numbers in blood pressure mean?
X/Y
X = systolic pressure Y= diastolic pressure
What is a normal blood pressure?
120-140 / 60-80
What is an arithmea?
When the parts of the heart don’t perform functions at the same time.
How does the heart muscle regulate itself?
It is Myogenic. So it produces its own em (only roughly 40bpm). Cells in the heart known as pacemaker cells generate a current by pumping ions in and out of the cell at speed using facilitated diffusion and active transport.
What parts of the heart are responsible for keeping the beat?
SAN- sind atrial Node - contains pacemaker cells
AVN- atrio ventricular node- delays the signal
Bundle of his- carries the signal to…
Purkyne fibres - nerves that contract the ventricles
What is PQRST
P = atriums contracting QRS= ventricles contracting T = recovery wave
What is vsystolic and asystolic?
V systolic, atriums seized
A systolic, ventricles seized
What is cardiac output
Volume of blood being pumped around the body by the heart in 1 min units = dm3/min-1
Cardiac output =
Stroke volume x heart rate
Describe capillaries
1 cell thick (only endothelium lining) this makes them weak and leaky ( due to capillary pores and not being a perfect fit) this allows monomers (A.A etc) to pass through and filter into cells. Due to its thinness it is very efficient at diffusion!
What makes up tissue fluid?
Plasma (dissolved substances) that has leaked out of capillaries
What is in plasma?
Dissolved substances eg: -hormones
- Glucose
- antibodies
- waste products
How is plasma forced out of the capillaries?
Through hydrostatic pressure and conc. gradient.
Is tissue fluid blood plasma?
NO! But they are quite similar!
How does tissue fluid work?
It fills the gaps between cells and allows nutrients to get to cells and waste to be removed
