Flashcards in 1.2 The Respiratory System Deck (30)
Getting air into and out of the lungs
Define external respiration?
Gaseous exchange between the lungs and blood.
Define internal respiration?
Exchange of gases between the blood in the capillaries and the body cells.
Define cellular respiration?
The metabolic reactions and processes that take place in a cell to obtain energy from fuels such as glucose.
Describe the passage of air?
Air is a mixture of gases and is drawn into the body through the nose -> It passes through the pharynx and onto the larynx (voice box) -> Then down the trachea (windpipe) and into the right and left bronchus -> Air moves through each bronchus and they subdivide into secondary bronchi -> These then get progressively thinner and branch into bronchioles and then respiratory bronchioles, which lead into the alveoli.
What’s the memory tool to remember the passage of air?
The movement of gas particles from an area of high concentration or partial pressure to an area of low concentration / partial pressure.
Define gaseous exchange?
The movement of oxygen from the air into the blood, and carbon dioxide from blood into the air.
Describe the structure of the alveoli?
The structure of the alveoli is designed to help gaseous exchange. Their walls are very thin (only one cell thick) which means there is a short diffusion pathway.
What’s the function of the alveoli?
The alveoli are responsible for the exchange of gases between the lungs and the blood. This occurs via diffusion.
Describe the mechanics of breathing?
The greater the difference in pressure, the faster air will flow. This means that in order to get air to the lungs (inspiration), the pressure needs to be lower here than in the atmosphere. To get air out (expiration), air pressure needs to be higher in the lungs than the atmosphere. Increasing the volume of the thoracic cavity (chest cavity) will reduce the pressure of air in the lungs. Decreasing the volume of the thoracic cavity will increase the pressure of air in the lungs, forcing the air out.
During inspiration what muscles are used during breathing at rest?
During inspiration what muscles are used during exercise?
During expiration what muscles are used during breathing at rest?
Passive: diaphragm and external intercostals just relax.
During expiration what muscles are used during exercise?
Define tidal volume?
Volume of air breathed in or out per breath.
Define Inspiratory Reserve Volume (IRV)?
Volume of air that can be forcibly inspired after a normal breath.
Define Expiratory Reserve Volume (ERV)?
Volume of air that can be forcibly expired after a normal breath
Define lung volumes?
This is the movement of air into and out of the lungs. Taking air into the lungs is inspiration and moving air out is expiration.
Define residual volume?
The amount of air that remains in the lungs after maximal expiration.
Define minute ventilation?
Volume of air breathed in or out per minute.
What is a spirometer?
A device that is used to measure the volume of air inspired and expired by the lungs. (The volume of air we breath in or out).
Define partial pressure?
The pressure exerted by an individual gas when it exists within a mixture of gases.
What is the function of intercostal muscles?
Intercostal muscles help your breath in, e.g the diaphragm flattens which allows more air to enter the lungs.
Define the concentration/diffusion gradient?
Often referred to as the concentration gradient. It explains how gases flow from an area of high concentration to an area of low concentration. The steeper this gradient (difference between concentration levels at high and low area), the faster diffusion occurs.
What’s the memory tool for Pulmonary Ventilation?
Pulmonary ventilation simply means breathing!
What’s the memory tool for the order of neural/chemical control for inspiration?
Receptors = medulla = phrenic nerve = diaphragm and external intercostals
What is the memory tool for the order of neural/chemical control for expiration?
Receptors = medulla = intercostal nerve = abdominals and internal intercostals.
Celia a microscopic hairlike projections that help to sweep away fluids and particles.