B11 - gas exchange (respiratory system) Flashcards
name the 11 parts in a lung structure
-larynx (voice box)
-trachea
-bronchus
-bronchioles
-alveoli
-diaphragm
-ribs
-intercostal muscles
-external costal muscles
-lungs
-pleural fluids and pleural membrane
what’s the function of larynx (voice box)
-air passes through
-vocal cords vibrate to make sound
what’s the function of bronchus
-split from trachea
-2 of them
-left bronchi to left lung , right bronchi to right lung
- narrower than trachea
what’s the function of trachea
-an open tube with C-shaped rings of cartilage (this makes it strong and allows it to move)
-carries air to bronchus
-lined with goblet cells and ciliated cells
what’s the function of bronchioles
-split from bronchus
-very narrow branch that leads to the alveoli
what’s the function of alveoli
-site of gas exchange
-1 cell thick
-covered with network of blood capillaries
what’s the function of ribs
-protect lungs
what’s the function of lungs
-made up of millions of alveoli
what’s the function of intercostal muscles
-lower rib cage
what’s the function of external costal muscles
-lift rib cage
what’s the function of pleural membrane
-lubricates when lungs move (reduce friction)
what’s the function of pleural fluid
-lubricates when lungs move (reduce friction)
what’s the function of diaphragm
-a sheet of muscle
-separate respiratory system from the lower part of the body
-contracts (goes down) in inhalation / moves up and down
what is throat
pharynx
what is chest
thorax
composition of oxygen in inspired air
21%
composition of oxygen in expired air
16%
composition of carbon dioxide in inspired air
0.04%
composition of carbon dioxide in expired air
4%
composition of nitrogen in inspired and expired air
78%
composition of water vapor in inspired air
variable
composition of water vapor in expired air
saturated
composition of other gases (eg. argon) in inspired and expired air
less than 0.1%
composition of temperature in inspired air
variable
composition of temperature in expired air
37 degrees (warm)
reason for difference in composition of oxygen in inspired and expired air
-oxygen is used up in aerobic respiration
reason for difference in composition of carbon dioxide in inspired and expired air
-carbon dioxide is a waste product of aerobic respiration
reason for no difference in composition of nitrogen in inspired and expired air
-nitrogen is not used in aerobic respiration
reason for difference in composition of water vapor in inspired and expired air
-water is a waste product of aerobic respiration
reason for difference in composition of other gases in inspired and expired air
-they are not used in aerobic respiration
reason for difference in composition of temperature in inspired and expired air
-heat energy is released during aerobic respiration
carbon dioxide in expired air experiment
-2 tubes of lime water
-a mouth piece connected to 2 separate tubes- on touches the limewater in the tube, other doesn’t
-when breathe in - tube with tube not in limewater bubbles - air from room is drawn, air contains little carbon dioxide so limewater stays same
-when breathe out - tube with tube in line water bubbles - expired air is released and contains lots of carbon dioxide - lime water turn milky white
oxygen in expired air experiment
-have a burning candle in a jar with normal air - candle burns for a while
-have a burning candle in a jar with expired air - candle burns for a short while
-there is little oxygen in expired air than inspired air - candle burns shorter in expired air
What does alveolus have in them
a layer of moisture
what does the layer of moisture in alveolus do
dissolve oxygen
4 advantageous features of alveolus
-large surface area
-1 cell thick
-network of capillaries surround the alveolus
-well ventilated
how does a large surface area help the alveolus
-many molecules can diffuse across at the same time - increases rate of diffusion
how does being 1 cell thick help the alveolus
-short distance for diffusion - increases rate of diffusion
how does a network of capillaries surround the alveolus help the alveolus
-the moving blood brings carbon dioxide and remove oxygen
how does well ventilation help the alveolus
-keeps oxygen concentration high - 21%
-keeps carbon dioxide concentration low- 0.04%
-maintains a steep concentration gradient for diffusion to take place - steep = increased rate of diffusion
order of process when inhaling
-ventilation (breathing)
-gas exchange
-aerobic respiration
define ventilation
-movement of air in and out of lungs by breathing movement
define gas exchange
-diffusion of oxygen and carbon dioxide in and out of an organism’s body
define aerobic respiration
-chemical reaction in cell that break down nutrient molecules and release energy using oxygen
Note: when finding left and right of a diagram- their right is your left
experiment to investigate the effects of physical activity on breathing rate
-rest for 1 minute
-count the number of breathes taken in 30s and double it
-run for 1 minute
-count the number of breathes taken in 30s and double it
what is depth of breathing also called
tidal volume
what measures the tidal volume and breathing rate
spirometer
explain the cause of increased breathing rate and depth
- increased muscle contraction
- more energy
- more aerobic respiration - more oxygen needed and carbon dioxide produced
- increased carbon dioxide in blood
- makes carbonic acid - toxic (ph decreases)
- brain senses drop in ph in blood
- brain sends nerve impulse to diaphragm and intercostal muscles to increases rate and depth of breathing
- increased ventilation
- more gas exchange
where is the highest concentration of oxygen in an alveolus
in the alveolus
note: when a Q asks to explain the difference in breathing before and after exercise - add cause + reason 1/2 of cause
eg. breathing rate is faster because more energy needed
note: answer Q carefully based on what the Q wants
effect of exercise on pattern of breathing
-increased breathing rate / depth
- (due to) increased carbon dioxide concentration in blood
- (because) carbon dioxide is a waste product of respiration
what does increased breathing rate do
-increased tidal volume
what does increased heart rate do
-transport oxygenated blood faster
why do you repeat experiment many times
-allows mean to be calculated
-can find anomalies
