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
Explain how lung cancer is formed
Carcinogens damage the dna of cells
Which causes them to mutate and divide uncontrollably which is called a tumor
The Tumour can now spread to other parts of the body and can damage other cells
Why is carbon monoxide dangerous
It binds more tightly to the haemoglobin in the blood than oxygen does
So less oxygen is transported around the body
So cells can not respire as well and the person will have difficulty breathing
Why would a pregnant woman who smokes child be underweight
Carbon monoxide present in a cigarette will bind more tightly with the haemoglobin in the fetuses red blood cells
and so less oxygen will be transported to the cells if it’s body
So less aerobic respiration will take place
Which will alter the growth and development of the fetus
What are two withdrawal symptoms of smoking
Restlessness
Tendency to put on weight
Explain how a smoker can quit and how it works
They can begin consuming nicotine gum or vapes which do not contain tar
This way their body has a source of nicotine but is not affected by the tar
Gradually they can decrease their nicotine dose and they will not crave it anymore
Name three harmful substances present in a cigarette and describe what they do
Tar:causes cancer, bronchitis and emphysema
nicotine: addictive stimulant that causes high cholesterol
carbon monoxide: prevents blood from carrying oxygen
Name five components that blood transports and name from where to where
Oxygen and carbon dioxide
Nutrients from the gut to other parts of the body
Urea from liver to kindey
Hormones and antibodies
Heat
Why do multicellular organisms require a circulatory system
Their body is made of many cells
so they have a small surface area to volume ratio
so oxygen can not diffuse fast enough into cells and they would die
Why do we need blood to be pumped to put lungs
So that gas exchange can take place (so oxygen can go into the blood stream and carbon dioxide can go out)
Describe the difference between a single circulatory system and a double circulatory system
In a Single circulatory system, blood is pumped from the heart to the gas exchange organ and then to the rest of the body
But in a double circulatory system, blood is pumped from the heart to the gas exchange organ to the heart again to the rest of the body
Describe the sequence of pulmonary circulation and the sequence of systemic circulation
Pulmonary circulation:
deoxygenated blood —) pulmonary artery—) lungs—) pulmonary vein —) rest of the body
Systemic circulation:
oxygenated blood —) aorta —) rest of the body —) vena cava
Describe the direction of blood movement in the arteries, veins, capillaries
Arteries: away from the heart to other parts if the body
Veins: from other parts of the body to the heart
Capillaries: carry blood through organs, linking the arteries and capillaries
Explain the process of how deoxygenated blood enters the heart and how it returns back to the heart(6)
Deoxygenated blood enters the VENA and then enters the RIGHT ATRIUM, which contracts so pressure increases and the TRICUSPID VALVW opens to allow blood to flow into the RIGHT VENTRICLE
This contracts so the pressure increases and forces the blood to flow into the SEMILUNAR VALVE
From where it leaves through the PULMONARY ARTERY
Where it travels into the lungs through the CAPILLARIES through the alveoli
And then is transported back to the heart through the PULMONARY VEIN
Explain the process of how oxygenated blood enters the heart and then how it returns back to the heart(5)
Oxygenated blood enters through the PULMONARY VEIN into the LEFT VENTRICLE, where this contracts and thus increases the pressure to force blood to flow through the BICUSPID VALVE into the LEFT VENTRICLE
The left ventricle also contracts to increase the pressure, forcing the blood into the SEMILUNAR VALVE
where from here the blood leaves through the AORTA and the high pressure closes the VALVE
and then travels to other parts of the body and then enters from the VENA CAVA
Explain why the diameter of the walls of the left ventricle are thicker than the walls in the right ventricle
Left ventricle is thick To withstand higher pressures to allow blood to flow through the whole body.
Right ventricle is thin To carry Lower pressure blood in order to prevent damage in the capillaries of the lungs
What is the largest artery in the body
The aorta
Give six adaptations of the heart:
1)split into two ventricles to allow different pressures, where left ventricle is thicker than the right ventricle because it pumps blood to whole body
2)walls of the atria are thin, which stretch when blood enters and contract to push blood through the tricuspid and bicuspid valves
3)made of cardiac muscle, which can continuously contract and expand without being fatigued
4)cardiac muscle has its own blood supply through coronary arteries and coronary veins which can supply it with oxygen and nutrients so that it can continue to contract and expand
5)contain valves which allow blood flow in only one direction
6)split by a septum which separates oxygenated and deoxygenated blood