The cardio-respiratory system-basics! Flashcards
What does the cardio-respiratory system consist of?
heart, blood vessels and lungs
What is the main function of the cardio-respiratory system?
transportation of O2 and nutrients and removal of waste products (inahling o2 ad exhaling CO2 )
What is circulation and what is the 2 types of circulation?
flow of blood moving thru the body 2 types:
-Pulmonary circulation- network of blood vessels around lungs
-systemic circulation-arteries & veins
What is the effect of exercise on the cardio-respiratory system?
-exercise causes an increase in demand for oxygen and nutrients, respiratory rate, heart rate, production of CO2 and blood flow
Describe where the heart is located?
-Located in thoracic cavity
-sits medially between lungs
-top of heart is called base
-bottom of heart is called apex
Describe the difference between the right and left side of the heart?
Left side- supplies systemic circulation receives blood from lungs
Right side- receives deoxygenated blood from body and pumps it to lungs to be oxygenated
Describe the movement of blood through the heart?
-Blood comes from lungs via the pulmonary veins and starts to gather and build up in left atrium
-Blood passes through mitral valve (forced open by build up of blood) and into left ventricle (muscular- is in charge of pushing blood around the body- generates blood pressure)
-when heart contracts blood comes out of left ventricle and out of the aortic valve into the body
-when blood comes bcak to heart thru 2 veins (superior vena cava-brings blood back from body and inferior vena cava- brings blood back from lower body)
-Blood pulls in right atrium and then passes thru tricuspid valve into right ventricle
-when right ventricle pumps and heart contracts, blood is pumped out of pulmonary valve into pulmonary trunk
describe the effect of pressure on blood flow within the cardio-respiratory system?
-Blood moves thru valves due to pressure changes in heart
-can only move from areas of high pressure to areas of low pressure
Eg. pulmonary hypertension- pressure is too high in pulmonary artery
-Displayd by Wiggers diagram
Describe the 2 phases of the cardiac cycle?
Diastole (relaxation)& systole (contraction)
Diastole
-left and right ventricle start to fill
-After filling the blood left in both ventricles is called end diastolic volume
Systole
-heart contracts, pushing blood out, not all blood is pushed out, a little amount is left- called end systolic volume
Formula to calculate stroke volume?
EDV-ESV
What is the Bohr shift?
when O2 dissociates from haemoglobin into muscles at a faster rate
What is the acute response to exercise displayed within the heart?
-O2 demand increases
-Causes an increase in heart rate (chronotropic), stroke volume and therefore cardiac output.
-Inotropic- increase in contractility
–Increased O2 uptake from muscles causing Bohr shift
-Increase in A-v O2 diff as more oxygen is extracted from tissue (less O2 in arteries)
What is A-v O2 diff
Aterio-venous O2 difference (difference in O2 content between arteries and veins)
-(when someone has exercised to the max they reach their VO2 max (A-v O2 diff is limited)
-VO2max= maximum oxygen consumption
What is the Fick equation for VO2 max?
VO2 max= Q x (A-vO2 diff)
-(Q= HR x SR)
What is the 3 main roles of blood vessels in the body?
-Transportation- O2, hormones, nutrients, waste product removal
-Communication- substances travel in blood which facilitate communication
-Homeostasis- maintaining temperature and blood pressure