The Respiratory System Flashcards
what areas are involved in the Respiratory System
-Nasal Cavity -Larynx
-Mouth -Pharynx
-Lungs -Trachea
-Right Bronchi -Left Bronchi
-Bronchioles -Alveoli
-Diaphragm -Epiglottis
-Internal Intercostal Muscles
-External Intercostal Muscles
Nasal Cavity
We breathe air in, Hairs filter out the dust
Pharynx
Connects the Nasal Cavity with the Larynx, it is a pathway for air and food
Larynx
Known as the voice box, contains vocal cords, it connects the Pharynx with the Trachea
Trachea
Known as our windpipe, 12cm long, rigid rings of cartilage prevent collapse
Epiglottis
Small flap of cartilage, closes over the top of the Trachea when you swallow food, prevents food travelling to your lungs
Lungs
-Your lungs are the organ that allows oxygen to be drawn into the body.
-The paired right and left lungs occupy most of the Thoracic Cavity.
-They Extend down the Diaphragm
Bronchi
-The Bronchi branch of the Trachea and carry air to the lungs
Bronchioles
Small airways that extend from the Bronchi to small clusters of thin walled air sacs, This is known as alveoli
The Alveoli
-They are the site of gaseous exchange
-Oxygen is diffused through the alveoli into the blood capillary
-Carbon dioxide is diffused from the blood capillary, into the alveoli
Characteristics of the Alveoli
- One cell thick
- Short diffusion pathway
- Semi-permeable membrane
- Good blood supply
- Small in size, large in amount
- Big surface area
The Diaphragm
A flat Muscle, located beneath the lungs. It supports the mechanics of breathing. Drawing in air(Oxygen). Breathing out air(Carbon Dioxide)
Internal Intercostals
Lie inside the ribcage they draw the ribs downwards and inwards. Decreasing the volume of the chest cavity, forcing air out the lungs when breathing out
External Intercostals
Muscles lie outside the ribcage. They pull the ribs upwards and outwards. Increasing the volume of the chest cavity and drawing air into the lungs when breathing in
How does the Diaphragm move when we inspire?
the diaphragm contracts and pulls
How does the Diaphragm move when we expire?
the diaphragm relaxes
The alveoli are a site for what process?
gaseous exchange
What flap of cartilage closes over the top of the trachea when swallowing?
Epiglottis
3 characteristics of the alveoli
- One cell thick
- Short diffusion pathway
- Semi-permeable membrane
- Good blood supply
- Small in size, large in amount
- Big surface area
Internal intercostals move the ribs?
move the ribs down and in
External intercostals move the ribs?
move the ribs upwards and out
How does the movement of the diaphragm and internal intercostals enable effective expiration?
Diaphragm rises into a dome shape and internal intercostals move the ribs down and in. this creates a smaller space inside the thoracic cavity and a higher pressure. air then moves down the concentration gradient(high to low) and we breathe in
How does the movement of the diaphragm and external intercostals enable effective inspiration?
Diaphragm contracts and pulls flat and external intercostals move the ribs up and out. this creates a bigger space inside the thoracic cavity and a lower pressure. air then moves down the concentration gradient(high to low) and we breathe in
How does oxygen move during gaseous exchange?
Oxygen moves from the alveoli to the bloodstream
How does carbon dioxide move during gaseous exchange?**
Carbon dioxide moves from the bloodstream to the alveoli
Lung Volumes
Our lungs are designed to take in more air during exercise so that more oxygen can reach the alveoli and more carbon dioxide can be removed. Breathing becomes deeper and more frequent to cope with the demands of exercise.
Lung Volumes
- Inspiratory Reserve Volume
- Tidal Volume
- Expiratory Reserve Volume
- Residual Volume
- Total Capacity
Tidal Volume
- The volume of air breathed in and out per breath
How does tidal volume change during exercise?
Tidal volume increases during exercise
What are the average tidal volumes for men and women?
- Average volumes for men: 0.5 litres/min
- Average volumes for women: 0.5 litres/min
Inspiratory Reserve Volume
The additional volume of air that can be forcibly inhaled after respiration of normal tidal volume**
How does inspiratory reserve volume change during exercise?
Inspiratory reserve volume decreases during exercise
What are the average inspiratory reserve volumes for men and women?
- Average volumes for men: 3.0 litres/min
- Average volumes for women: 1.9 litres/min
Expiratory Reserve Volume
The additional volume of air that can be forcibly exhaled after expiration of normal tidal volume**
How does expiratory reserve volume change during exercise?
Expiratory reserve volume decreases during exercise
What are the average expiratory reserve volumes for men and women?
- Average volumes for men: 1.5 litres/min
- Average volumes for women: 0.7 litres/min
Residual Volume
The volume of air that remains in the lungs after maximal expiration
How does residual volume change during exercise?
Residual volume stays the same during exercise
What are the average residual volumes for men and women?
- Average volumes for men: 1.2 litres/min
- Average volumes for women: 1.1 litres/min
Vital Capacity
The maximum amount of air that can be breathed out after breathing as much air in as possible
How does vital capacity change during exercise?
Vital capacity does not change during exercise
What are the average vital capacity volumes for men and women?
- Average volumes for men: 4.8 litres/min
- Average volumes for women: 3.3 litres/min
Total Lung Volume
Your total lung capacity after you have inhaled as deeply as you can
What are the total lung capacities volumes for men and women?
- Average volumes for men: 6.0 litres/min
- Average volumes for women: 4.4 litres/min
Control of Breathing
Breathing is a very complex process that is largely controlled by respiratory centres in the brain.
When we talk about how breathing is controlled we make reference to either neural or chemical control
Neural Control of Breathing
- Inspiration at rest is an active process(the diaphragm contracts)
- Expiration at rest is a passive process(the diaphragm relaxes)
- This process is not possible without neurones in the brain stem. These neurones exist in two areas of our medulla oblongata.
Chemical Control of Breathing
Another factor that controls our breathing is the changing levels of oxygen and carbon dioxide (acidity) in the blood. The sensors that respond to these chemical fluctuations are called chemoreceptors. They are found in the aortic arch and carotid artery.
Chemoreceptors
- Detect changes in the blood, carbon dioxide levels as well as changes in blood acidity.
- Low concentration of oxygen(O2)
- High concentration of carbon dioxide(CO2)
- They send signals to the medulla oblongata that makes changes(increase) Breathing rate, causing the diaphragm and intercostals to work harder.
How does the diaphragm move when we inspire
It contracts
How does the diaphragm move when we expire
It relaxes
The ‘alveoli’ are the site for what process
Gas diffusion over a partially permeable membrane
What flap of cartilage closes over the trachea when swallowing
The epiglottis
Provide 3 characteristics of the alveoli
- One cell thick
- Short diffusion pathway
- Semi-permeable membrane
- Good blood supply
- Small in size, large in amount
- Big surface area
How do the internal intercostals move the ribs
Downwards and Inwards
How do the external intercostals move the ribs
Up and Out
The mechanics of breathing
Breathing(Pulmonary ventilation) is a process by which air is transported into and out of the lungs.
it has 2 phases and requires the thoracic cage to change shape.
Altering the space/pressure inside
The concentration gradient
- Gases(air) move down a concentration gradient
- Gases always move from an area of high pressure to low pressure
- Sometimes pressure is referred to as concentration
Inspiration
The diaphragm contracts and pulls flat, the external intercostals move the ribs up and out.
This creates a bigger space and a lower pressure.
Air then moves from a high concentration(the atmosphere) to a low concentration(the lungs)
Expiration
The diaphragm rises into a dome shape and the internal intercostals move the ribs down and in.
This creates a smaller space and a higher pressure.
Air then moves from a high concentration(the lungs) to a low concentration(the atmosphere)
Gaseous exchange
Involves one type of gas being exchanged for another in the lungs, gaseous exchange occurs by diffusion between air in the alveoli and blood in the capillaries surrounding their walls.
The movement of carbon dioxide
Blood enters the capillaries from the pulmonary artery(the major blood vessel that pumps deoxygenated blood from the heart to the lungs) it has a lower oxygen concentration and a higher carbon dioxide concentration than the air in the alveoli.
Carbon dioxide moves from where it is highly concentrated(the blood) to where it is less concentrated(the alveoli) when we breathe it out
The movement of oxygen
Oxygen diffuses into the blood via the surface of the alveoli, through the thin walls of the capillary and into the bloodstream, now oxygenated; it latches onto haemoglobin.
Oxygen moves from where it is highly concentrated(the alveoli) to where it is less concentrated(the blood)
