Structure and Function of Cardio-respiratory system Flashcards
Where does gaseous exchange take place?
Gaseous Exchange takes place in the aveoli.
What are the 5 stages for the pathway for air?
- Air enters the body and is warmed as it travels through the mouth and nose.
- It then enters the trachea.
- The trachea divides into two bronchi. One bronchus enters each lung.
- Each bronchus branches out into smaller tubes called bronchioles. Air travels through these bronchioles.
- At the end of the bronchioles, the air enters one of the many millions of alveoli where gaseous exchange takes place.
Name 3 characteristics of aveoli?
- they give the lungs a really big surface area
- they have moist, thin walls (just one cell thick)
- they have a lot of tiny blood vessels called capillaries
What is the 4 stage process of gaseous exchange?
1) Oxygen that has been breathed in passes through the aveoli (air sacs) and into the red blood cells in the capillaries.
2) The oxygen combines with the haemoglobin to form oxyhaemoglobin.
3) At the same time an enzyme in the red blood cells breaks down the CO2 in the blood and turns it into a gas.
4) The CO2 in the capillaries then passes through the aveoli and into the red blood cells in the capillaries.
What does inspiring mean?
Inspiring- Breathing in
What does expiring mean?
Expiring- Breathing out
What are the mechanics of breathing when your are inspiring?
When you are at rest and inhaling, the diaphragm flattens and moves downwards and the intercostal muscles contract, which raises the ribs up, making the chest cavity larger. This reduces the air pressure inside the chest cavity, which in turns causes air to be sucked into the lungs.
What are the mechanics of breathing when you are expiring?
When you are contracting and exhaling, the diaphragm relaxes and domes and moves upwards which effectively makes the chest cavity smaller. This increases the air pressure in the chest cavity, which in turn causes air to be pushed out of the lungs.
What is a spirometer trace?
Spirometer Trace- is a measure of lung volumes.
What does tidal volume mean?
Tidal Volume- The volume of air inspired or expired/ exchanged in each breath
What does Inspiratory reserve volume mean?
Inspiratory reserve Volume- The amount of air that could be breathed out after tidal volume.
What does expiratory reserve volume mean?
Expiratory reserve Volume- The amount of air that could be breathed out after tidal volume.
What does residual volume mean?
Residual Volume- The amount of air left in the lungs after maximal expiration.
What does Cardio Cycle mean?
Cardio Cycle- The process of the heart going through the stages of systole and diastole in the atria and ventricles.
What does diastolic blood pressure mean?
Diastolic Blood Pressure- When the heart is relaxing
What does Embolism mean?
Embolism- The blockage of a blood vessel
What does haemoglobin mean?
Haemoglobin- The substance in red blood cells which transport oxygen (as oxyhaemoglobin) and carbon dioxide.
What does Hypertension mean?
Hypertension- High blood pressure in the arteries.
What does Systolic Blood Pressure mean?
Systolic blood Pressure- When the heart is contracting.
What does Vasoconstriction mean?
Vasoconstriction- Narrowing of the internal diameter of a blood vessel to decrease blood flow.
What does Vasodilation?
Vasodilation- Widening of the internal diameter of a blood vessel to increase blood flow.
Explain the pathway of blood in 5 stages.
1) The oxygenated blood enters the right atrium. At this time it is dark red with little oxygen but mainly waste products e.g CO2.
2) The right atrium pumps the blood into the right ventricle through the bicuspid valve
3) The right ventricle pumps the blood through the pulmonary artery tot he lungs, where O2 is picked up, and CO2 is deposited. It is at this time that the blood changes colour to bright red because of he O2 it has collected.
4) From the lungs the blood returns to the left atrium through the pulmonary vein.
5) The left atrium pumps the blood into the left ventricle and the blood leaves here though the aorta to be distributed to the reds of the body.
What are the 3 types of blood vessels in the body?
- Arteries
- Veins
- Capillaries
Name 5 characteristics of arteries.
- Thick walls
- carry oxygenated blood at high pressure away from heart
- No valves
- More elastic walls then the veins
- They sub-dived into smaller vessels known as arterioles.
Name 4 characteristics of veins.
- carry deoxygenated blood back tot he heart
- Thinner walls than arteries
- Less elastic walls than arteries
- Has valves to ensure the blood doesn’t back flow
Name 3 characteristics of capillaries.
- Microscopic vessels
- Allow CO2 and O2 and waste products to pass through their walls
- Have very thin walls
What is the equation for Cardiac output?
Cardiac Output = Stroke volume x Heart rate
