cardiorespiratory system Flashcards
paper 1
describe the nose and mouth in the pathway of air into the lungs
air enters the body through here
describe the trachea in the pathway of air into the lungs
- air from the nose and mouth enters the wind pipe called the trachea
- the trachea is surrounded by rings of cartilage to keep its shape and prevent it collapsing
describe the bronchi in the pathway of air into the lungs
- air travels from the trachea and to each lung via a bronchus
- bronchi is the term for both the left and right bronchus
- the passage of air gets smaller and smaller
describe the bronchioles in the pathway of air into the lungs
- the smaller airways that branch off the bronchi are called bronchioles
- bronchioles branch out throughout the lungs and carry the air from the bronchi to the alveoli
describe the alveoli in the pathway of air into the lungs
- the bronchioles carry the air to the alveoli which are tiny air sacs
- they are attached to the bronchioles
- the exchange of oxygen and carbon dioxide occurs here
what is the order of the pathway of air into the lungs
- nose/ mouth
- trachea
- bronchi
- bronchioles
- alveoli
what are the different blood vessels
- artery
- vein
- capillary
describe an artery
- thick muscular walls
- thick elastic walls
- small lumen
- carries blood at high pressure
- carries blood away from the heart
- carries oxygenates blood (except pulmonary artery)
describe a vein
- thin walls
- large lumen
- carries blood at low pressure
- contain valves (prevent backflow)
- carries deoxygenates blood (except pulmonary vein)
describe a capillary
- very thin walls (one cell thick)
- small lumen
- link smaller arteries with small veins
- allows gaseous exchange
- carries blood at low pressure
describe gaseous exchange
- gases move from areas of high concentration to areas of low concentration (diffusion)
- oxygen is diffused into the blood, it binds with haemoglobin to form oxyhaemoglobin
- oxyhaemoglobin is transported to the working muscles where it is used for aerobic activity
- during aerobic activity carbon dioxide is produced- removed from the muscles by haemoglobin
- gaseous exchange occurs at the alveoli- capillaries- muscle tissue
how is the alveoli adapted for gaseous exchange
- have tiny air sacs with moist thin walls (one cell thick)- short diffusion distance
- have a large surface area- contain millions of alveoli
- surrounded by capillaries- maintains concentration gradient and provides a large blood supply
why/ when is blood redistributed
- when we exercise
- the working muscles need more oxygen than other inactive areas of the body such as the stomach
- blood is diverted away from inactive areas to the working muscles
what is vasoconstriction
- blood vessels constrict, make them smaller
- chemical changes signal the nervous system to constrict blood vessels to inactive areas
what is vasodilation
- blood vessels dilate to make them bigger
- chemical changes signal the nervous system to dilate blood vessels that supply active areas
what is cardiac output
amount of blood leaving the heart per minute
what is stroke volume
amount of blood ejected from the heart per beat
what is heart rate
number of times the heart beats per minute
describe the mechanics of breathing during inspiration
- diaphragm and external intercostal muscles contract
- ribs move upwards and outwards
- chest cavity volume increases
- air is forced into the lungs
describe the mechanics of breathing during expiration
- diaphragm and external intercostal muscles relax
- ribs lower and move downwards and inwards
- chest cavity decreases in volume
- air is forced out of the lungs
describe the mechanics of breathing during inspiration during exercise
pectorals and sternocleidomastoid muscles raise the sternum allowing the lungs to expand further
describe the mechanics of breathing during expiration during exercise
rib cage is pulled down quicker due to the abdominal muscles contracting
what is tidal volume
the amount of air inspired or expired in a normal breath
what is vital capacity
the maximum amount of air the lungs can expire after the maximum inspiration
what is the expiratory reserve volume
the maximum volume of air that can be exhaled in addition to tidal volume
what is the inspiratory reserve volume
the maximum volume of air that can be inhaled in addition to tidal volume
what is residual volume
the amount of air that remains in the lungs even after a forced maximal exhalation
fill in the gaps:
tidal volume during exercise _________. Breathing rate and depth _______ due to meet the demand of oxygen, ______ _______ is also removed
- increases
- increase
- carbon dioxide
what is it called when immediately before exercise the heart rate increases
- anticipatory rise
- due to the release of the hormone adrenaline
when you start to exercise, heart rate increases- why?
- due to the demand of oxygen
- thus cardiac output also increases
fill in the blanks:
during __________ exercise, heart rate levels because it is sustaining the amount of ______ needed
immediately after exercise, heart rate ________ sharply, as exercise has stopped and the demand for oxygen has _______
- continuous
- oxygen
- decreases
- reduced
state the cardiac cycle pathway of blood (starting from right ventricle)
- right ventricle
- pulmonary artery
- lungs (gaseous exchange- blood is oxygenates)
- pulmonary vein
- left atrium
- left ventricle
- aorta
- body (gaseous exchange- blood is deoxygenated)
- vena cava
- right atrium
- right ventricle (cycle repeats)
what happens at the right ventricle in the cardiac cycle
- it relaxes (diastole) and fills with deoxygenated blood
- then contracts (systole) pushing the deoxygenated blood through the valves to the pulmonary artery
what happens at the pulmonary artery in the cardiac cycle
- carries deoxygenated blood away from the heart to the lungs
- blood becomes oxygenated
what happens at the pulmonary vein in the cardiac cycle
- transports the oxygenated blood back to the heart and into the left atrium
what happens in the left atrium in the cardiac cycle
- fills with oxygenated blood
- contracts (systole) ejecting oxygenated blood through a valve and into the left ventricle
what happens in the left ventricle in the cardiac cycle
- it relaxes (diastole) and fills with oxygenated blood
- then contracts (systole) pushing the oxygenated valves to the aorta
what happens at the aorta in the cardiac cycle
- carries oxygenated blood away from the left ventricle to the working muscles
- the blood then becomes deoxygenated
what happens at the vena cava in the cardiac cycle
- is the main vein bringing deoxygenated blood back to the heart and into the right atrium
what happens at the right atrium in the cardiac cycle
- contracts (systole) ejecting deoxygenated blood through a valve and into the right ventricle
what is systole and diastole in the cardiac cycle
SYSTOLE
- occurs when the heart contracts to pump blood out
DIASTOLE
- occurs when the heart relaxes and refills with blood
