Breathing, Gas Exchange, Cirrculatiry System Flashcards
What is the difference between respiration and breathing
Respiration is the chemical process that breaks down nutrient molecules (specifically glucose) in living cells to release energy
But breathing is the mechanism that brings air into and out of the lungs through gas exchange
What is the diapragm made of
A muscular sheet of tissues
What is the role of the cartilage around the trachea
It provides support to the trachea
and keeps the airways open when breathing
What is the role of the epiglottis
Acts as a flap to prevent food and water entering the windpipe
Describe how the trachea is kept clean
1)the goblet cells secrete mucus which trap dirt and bacteria
2)the cells are linked with cilia which sweep the mucus out towards the mouth
What is the role of the bronchi
To carry air to the lungs
What is the role of the bronchioles
The carry air from the bronchi to the alveoli
What are the roles of the pleural membranes
Provide lubrication to allow optimum expansion and contraction of the lungs
Explain how inhalation works
The outer intercostal muscles contract and MOVE THE RIB CAGE UPWARDS AND OUTWARDS
Whilst the diaphragm also contracts and dome flattens
So the volume inside the thorax is increased
So the pressure decreases in the thorax and is lower than that of atmospheric pressure
So air enters the lungs
Explain how exhalation works
The external intercostal muscles relax and the internal intercostals move the rib cage down
The diaphragm also relaxes and returns to its usual dome shape
The volume in the thorax decreases
So the pressure is higher than that of atmospheric pressure
So air is moved out of the lungs
How does the way that the lungs are made, help with exhalation
The lungs are elastic so they have a tendency to collapse
What is the percentage of oxygen Inhaled and exhaled
21% inhaled, 16% exhaled
What is the percentage of carbon dioxide inhaled and exhaled
0.04% inhaled and 4% exhaled
If hydrogen carbonate indicator is used for inhaled and exhaled air experiment, what colour will one of the tubes turn?
Exhaled air tube will turn yellow
Explain what happens to the breathing rate when a person exercises
When you exercise, your muscles contract more and your body needs to break down more ATP for energy,
Thus you need to respire more so your body needs to take in more oxygen and remove more carbon dioxide
So the rate and depth of breathing increases
Explain why the heart rate increases during excercise
Muscles contract more and need to break down more ATP for energy
So need to aerobically respire more and thus need to bring larger amounts of oxygen into the blood and need to remove larger amounts
therefore the heart needs to pump more blood per second so the heart rate increases
Explain why and how a fit persons resting heart rate differs from an unfit person
Fit person has a lower resting heart rate than an unfit person
Because training strengthens the heart
so they pump more blood per minute than an unfit person
Therefore can pump at a slower rate to supply oxygen to the aerobically respiring cells of the body
Why does a persons breathing rate and heart rate not return to normal after exercise
Because the build up of lactic acid needs to be oxidized by the oxygen debt
In the experiment of breathing in and out of a mouth tube to investigate inhaled and exhaled air, what can you say about the composition of inhaled air by looking at the test tube
The composition of inhaled air contains more oxygen than carbon dioxide and we know this because the limewater indicator only bubbled a small amount
Name three characteristics of the alveoli that make it efficient for gas exchange
1)good supply of oxygen to maintain concentration gradient
2)thin diffusion distance so can diffuse fast
3)large surface area to volume ratio, so that large amount of gases can diffuse in a short amount of time
Explain what happens when a person has bronchitis(4)
Tar destroys Cilia in the airways so they can not sweep mucus so there is a build up of dirt and bacteria
which blocks the airways and makes it difficult to breathe
And the lining of the cells are irritated
thus they produce more mucus which also builds up and causes a “smokers cough”
Explain how a smokers cough is formed
Tar irritates the lining of the cell which is then stimulated to produce more mucus
and it damages the cilia cells so mucus is unable to be swept away
So builds up in airways and causes the cough
Explain what happens when a person has emphysema(4)
Carcinogens damage the walls of the alveoli causing them to fuse together into large irregular shapes
This decreases the surface area of them
So gas exchange is made less efficient
So less oxygen can be dissolved in the blood stream
So the person has more difficulties breathing
Does smoking cause lung cancer
No but it increases the risk