Breathing And Respiratory System Flashcards
Respiration
> chemical reaction that occurs in all living cells
requires oxygen and glucose
products are carbon dioxide, water and energy in form of ATP
it’s not breathing
Word equation for respiration
Oxygen + glucose ——-> carbon dioxide + water + energy
Chemical equation for respiration
6O2 + C6H12O6 ——–> 6CO2 + 6H2O + energy
Uses of energy
- it provides heat ( maintaining body temperature at 37 degrees)
- it’s used to allow movement (muscle contraction)
- growth
- reproduction
- process of active transport (used by plants to absorb minerals from the soil)
How is carbon dioxide measured
Determined by:
- bicarbonate indicator (red/orange to orange/yellow)
- limewater (clear to cloudy)
Difference in gases inhaled and exhaled
Gas. Inhaled air%. Exhaled air%
Oxygen. 21. 16
Carbon dioxide. 0.04. 4
Nitrogen. 79. 79
Water vapour. Variable Always higher
Temperature. Variable. Always higher
Nasal cavity function
- contains many small hairs to filter air arriving into the body (ciliates cells)
- presence of many blood vessels also warms the air
Trachea function
- Carrie air to the lungs
- held open by rings of cartilage. They are not complete rings as the oesophagus is situated behind it and must be able to change shape as it passes chewed down it
- the walls are coated with mucus (produced by goblets cells). It catches any germs that may have been inhaled
- it is also known as the wind pipe
Bronchus function
These are branches of the tranches
Each branch delivers air to a lung
Also held open by cartilage
Bronchioles function
- smaller air tubes of hat for. From branches of the bronchi
- ensures air is delivered to all parts of the lungs.
Lung function
These are large organs where air enters and exits as we breathe
Alveoli function
- microscopic air sacs found at the end of bronchioles
- they are the site of gas exchange
- the surface is only one cells thick and is surrounded by many capillaries
Rib function
- bones surrounding many vital organs held within the chest cavity
- they are moved by the intercostal muscles during ventilation (breathing) causing pressure and volume changes in the chest cavity.
Diaphragm function
- a muscular sheet below the lungs
- it has the ability to contract and relax which alters the volume of the chest cavity
Intercostal muscles
Muscles found between the ribs that allows them to move during breathing
Pleural membranes and fluid function
The membranes surround the lungs and contains fluid. They ensure that friction is minimised during breathing
What happens when we breath in
Diaphragm contracts
and flattens
Volume of chest. Pressure in the. Air rushes
Increases (thorax). Chest decreases. in
Intercostal muscles
Contract raising the
Rib cage
What happens when we exhale
Diaphragm relaxes
+ returns to domed
position
Volume of chest. Pressure in chest. Air is forced
Decreases. Increases. Out
Intercostal muscles
relax + the rib cage
falls down + in
Key differences between the model lung and the respiratory system
> The balloons of the model don’t represent the:
-alveoli of the lungs
- the pleural fluid and membranes that surround them
-nasal cavity
-bronchioles
-cartilage holding the airways open
The glass jar can’t move, unlike the rib cage of the respiratory
system
The tubing of the model can’t flex like the tubes of the respiratory system
Adaptations of gas exchange surfaces
> surfaces should be thin to allow gas to diffuse across quickly
they should have mechanisms to maintain a steep concentration gradient
they should be moist
they should have a large surface area
How adaptations of gas exchange are achieved
> the walls of alveoli are one cell thick
the constant flow of blood and breathing in and out maintaining the gradient between the blood and the air
the alveoli are coated on layer of moisture that the gases dissolve into
the alveoli provide a larger surface area (side of tennis court in each lung)
Features that ensure that the rate of diffusion of gas is kept at a high level
> the wall of alveoli are one cell thick (short diffusion diffuse)
constant flow of blood and breathing in and out maintains th gradient between the blood and the air
gases dissolve into layers of moisture
Adaptations of red blood cells for carrying oxygen
- large surface area (biconcave shape
- no nucleus more shape for haemoglobin
What happens to oxygen in the lungs
The oxygen diffuses from the air in the alveolus into the blood and is used in the body for respiration
What happens the carbon dioxide in the lungs
The carbon dioxide diffuses from the blood into the air
Aerobic respiration
In the presents of oxygen
Anaerobic respiration
In the absents of oxygen
Aerobic word equation
Glucose + oxygen —-> carbon dioxide + water + energy
Aerobic chemical equation
C6H12O6 + 6O2 —–> 6CO2 + 6H2O + 2880 KJ
Anaerobic: yeast chemical equation
C6H12O6 —–> 2C2H2OH + 210 KJ (ethanol)
Anaerobic: human cells chemical equation
C6H12O6 ——-> 2C3H5OH + 150 KJ (lactic)
Anaerobic explanation
When there is no oxygen available a number of cells can continue to respire.
Differences between aerobic and anaerobic
- The amount of energy produced is much lower (1/10 of energy produce in anaerobic) This is because the glucose molecule isn’t fully broken down
- Oxygen is not used in anaerobic respiration
- Ethanol and lactic acid is produced in anaerobic
The manufacture of alcohol
Beer making uses barley
Barley grains contain malted sugar; this is cursed and combined with hops (to provide the flavour)
The sugar is then gradually converted to alcohol by yeast
Bread making
Uses yeast alone with sugar, flour and water
These are combined to form dough that is left to prove in a warm place (the dough can double in size during this process)
The proving time allows carbon dioxide bubbles to form in the dough-this is what gives bread its spongy characteristics
Bred is baked in jot oven (this evaporate the alcohol and kills the yeast)
Anaerobic respiration in humans
Strenuous, rapid exercise increases the amount of oxygen needed by the muscles
Eventually the breathing rate can’t meet the oxygen demand of the muscles and so the muscles cells begin to respire anaerobically
The lactic acid produced by anaerobic muscles cells in humans causes pain (it’s a mild poison)
To break down the lactic acid oxygen is needed (this is the oxygen debt)
Carbon dioxide is produced when yeast reprise anaerobically experiment
*it is important to boil water to remove only dissolved oxygen
>the sugar solution must be cooled of the high temperature will kill the yeast cells
>the liquid paraffin prevents any oxygen entering form the tube
>at the end the sugar solution containing living yeast you would expect to find alcohol/ethanol
Further explanation on the ‘carbon dioxide is produced when yeast respites anaerobically’
-more heat is produced the longer the yeast is under anaerobic conditions
-a control is to make a sample of glucose solution that doesn’t contain yeast + kept in the same conditions and repeat in aerobic conditions and compare
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