air enters our nose or mouth and passes down the windpipe (trachea)
(singular = bronchus)
two tubes which split from the tranchea, one which leads to each lung
smaller tubes which have been divided from each bronchus
micrscopic air sacs where air eventually ends up
here gas exchange with blood takes place
covered in blood capillaries
a muscular sheet of tissue
helps air move in and out of lungs
thin moist membranes inside the thorax which surround the lungs
stop lungs sticking to ribs (they are moist)
How does amoeba take up oxygen?
(organism found in ponds)
oxygen diffuses through its cell membranes
How do lungs take up oxygen?
lungs have a very large SA
we breath so oxygen can diffuse into our blood
What is the function of the respiratory system?
uptake of O2 (for respiration)
release of CO2 (waste product)
Label this structure of a respiratory system
Label this structure of an alveloi
of the lungs
towards the heart
away from the heart
Label this gas exchange in the alveoli diagram
Label this gax echange in one alveolus diagram
How big is a blood cell?
approximately 8 µm
How big is a blood capillary?
approximately 10 µm
What is so special about the size of a blood capillary?
it is extremely small
blood cells have to travel single file and often on their sides because otheriwise they can't fit
this allows diffusion time
How is the respiratory system's surface area adapted for efficient gas exchange?
very large surface area (60 cm2)
lots of capillaries - high surface area between capillaries and alveoli
How is the respiratory system's concentration gradient adapted for efficient gas exchange?
the air in the aveolus has a higher concentration of oxygen than the blood entering the capillary network - oxygen diffuses from the air to the blood
there is more carbon dioxide in the blood than there is in the air in the lungs
the concentration gradient is maintained as blood in constantly moving on - breathing in high concentration of oxygen , moving on and breathing out a low concentration
diffusion gradient for carbon dioxide is in the opposite direction to that of oxygen
blood which leaves the capillaries and flows back to the heart has gained oxygen and lost carbon dioxide
How is the respiratory system's diffusion distance adapted for efficient gas exchange?
very small distance - blood is only seperated by the cells making up the wall of the alveolus and the capillary wall itself
diffusion occurs rapidly
How is the respiratory system adapted for efficient gas exchange? (other points)
surfactant and moisture (stops alveolus from sticking together when it contracts)
moisture in surfactant dissolves O2 so it can enter the blood
breathing in and breathing out
Complete this table
Label this diagram of ribs
Label this diagram of intercostal muscles
What happens when you inhale?
diaphragm contacts (flattens)
external intercostal muscles contract
ribcage moves out and upward
volume of chest cavity increases
pressure inside decreases
air rushes into lungs to equalise pressure
What happens when you exhale?
diaphragm relaxes (moves upwards)
internal intercostal muscles contracts
ribcage moves down and inward
volume of chest cavity decreases
lung volume increases
pressure inside lungs increases
air flows out of lungs due to high pressure
Complete this inhalation diagram
Complete this exhalation diagram
Tidal Volume (TV)
volume of air breathed in and out in a single breath
Inspiratory Resolve Volume (IRV)
additional volume of air taken in with the deepest breath possible
up to 2L
Expiratory Reserve Volume (ERV)
additional volume of air that can be breathed out if we force it out
up to 1.5L
air remaining in your lungs after a maximum exhalation
IRV + TV + ERV
the maximum volume of air that can be exhaled in one breath
Complete this air in our lungs diagram
Describe what happens to the diaphragm to help a person breath
the diaphragm contracts; moves down/flattens
Name A, B and C
diffusion of oxygen from alveoli to capillary
higher concentration in alveoli
high to low concentration
concentration lower in capillary
down a concentration gradient
What effect would emphysema have on the value of oxygen uptake
lower value of oxygen uptake
Suggest how the air this person breathes can be altered to relieve the symptoms of emphysema
the concentration of oxygen is greater when breathed in
use of oxygen cylinder
what is inside a cigarette?
staeric acid (candle wax)
ammonia (toilet cleaner)
methanol (rocket fuel)
carbon monoxide (car exhaust smoke)
tar (road surfaces)
methane (sewer gas)
acetic acid (vinegar)
butane (lighter fluid)
what are the short-term effects of cigarette ingredients on the human body?
less oxygen to the brain
more coughs and colds
less oxygen to lungs (shortness of breat)
what are the long-term affects of cigarette ingredients on the human body?
gym disease and tooth decay
mouth and throat cancer
stomach and pancreatic cancer
peripheral vascluar diease
where does tar build up?
in the lungs
what causes emphysema and why?
chemicals in tar damage alveoli as the walls inbetween the sacs break down ---> SA reduced ---> less oxygen absorbed
what causes lung cancer and why?
tar contains carcinogens
what causes lung infections and bronchitis? why?
cilia paralysed so tar and mucus don't move up the throat to be coughed out or swallowed
bacteria reproduce ---> bronchitis
what does tar cause?
what is nicotine?
addictive substance in cigarettes
stimulates neurotransmiter in brain leading to more brain activity
what does nicotine cause and why?
strokes and heart attacks
constrict arteries reducing blood flow
fat deposited in blood vessels
increased blood pressure
what does carbon monoxide cause and why?
tiredness, dizziness, increased heart rate
binds irreversible to heamoglobin ---> reduces oxygen (carrying ability of red blood cells)
reduced birth mass ---> foetus gets less oxygen