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
What are the types of blood vessels- 3 main,2 smaller?
-Arteries- carry oxygenated blood away from heart
-Arteries then divide into Arterioles (regulate pressure and blood flow)
-Capillaries- where diffusion takes place
-venules- allow blood to move from capillary
-veins- transport deoxygenated blood back to heart (superior & interior vena cava)
Describe the similarities and differences within the structure of blood vessels?
-All have 3 layered membrane
-their structure can differ depending on function
-Arteries have thick walls, vein have thin walls
-veins have valves, arteries dont
-Cappilaries are a single cell layer, naturally thin-allows for efficient exchange
describe the effect of exercise on blood flow?
this is controlled and redistributed by blood vessels
-is redistributed during exercise
-Decrease in blood flow to stomach and kidneys compared to at rest- vasoconstriction
-Increase in blood flow to muscles- vasodilation in muscles
How does the arterioles regulate blood flow?
thru vasoconstriction (artery narrows) and vasodilation (artery gets wider)
What is metabolic isolation?
During exercise, more heat, more potassium and more CO2 wastage is generated in muscles
-This causes vasodialtion
What is venous return?
The volume of blood returning to the heart via the veins
Describe pressure within the blood vessels and how this helps with the transportation of blood?
-pressure inside blood vessels decreases with increased distance from heart
-Veins have valves as they are further away from heart- helps to push blood as there is a lack of pressure due to distance from heart. Valves are one way so help prevent reverse blood flow
-Skeletal muscle activation pump- increases during exercise in order to help transport more blood back to heart, increasing venous return
What are the 2 parts of the lungs?
Upper respiratory tract (Nasal cavity, pharynx, larynx) and lower respiratory tract (trachea, primary bronchi, lungs)
What is alveoli?
where gas exchange takes place in lungs (small tightly packed airs sacs located at end of bronchial tree)
Describe the transportation of gases through the lungs?
-Air enters by mouth and nose and travels down trachea
-Reaches bronchus travels thru to bronchioles then travels to alveoli in lungs
-Alveoli surround capillaries
-CO2 travels from capillaries to alveoli where it can be breathed out
-O2 that has been inhaled moves from alveoli into capillaries into the body for circulation
Describe the change in pressure within the lungs as we breathe in and out?
-As we breathe in and lungs fill with air, thoracic pressure increases
Concentration of O2 coming into alveoli is much higher than conc in blood stream so therefore blood moves into body for circulation
-As we breathe out thoracic pressure drops, there is a higher pressure of CO2 in capillaries than in alveoli so CO2 moves into alveoli and is exhaled
What are the features of the alveoli?
-Thin lining- allows for fast diffusion rate
-Large SA- speeds up diffusion as gases have larger area to diffuse across
-Rich blood supply due to network of capillaries, allowing large volumes to be exchanged
Describe the response of lungs to exercise?
-O2 demand increase
-Increase respiratory rate (more o2 in, more CO2 out
-Increase in depth of breathes, causing an increase in tidal volume
-Causes an increase in gas exchange due to capillary dilation (can take more in and push more out)
-Causes increase in alveoli surface area and ventilation
