Sport Anatomy: Respiratory System Flashcards
What is respiration?
The taking in of oxygen and the removal of carbon dioxide
What does respiration include?
. Ventilation
. External respiration
. Transport of gases
. Internal respiration
. Cellular respiration
What is ventilation?
Getting air into and out of the lungs
What is external respiration?
Gaseous exchange between the lungs and blood
What is internal respiration?
Exchange of gases between the blood in the capillaries and the body cells
What is cellular respiration?
The metabolic precautions and processes that take place in a cell to obtain energy from fuels such as glucose
How is air passed down the body?
It is drawn in through the nose, and passes down the pharynx and larynx and down the trachea. It then moves through the right and left bronchus and as they move through each bronchus they (bronchus) subdivide into secondary bronchi and then into thinner structures called bronchioles. Finally these lead to alveoli
What is alveoli responsible for?
Exchange of gases between lungs and blood
How does the alveoli conduct its exchange?
Via diffusion, the movement of gas molecules from an area of high partial pressure to an area of low partial pressure
What are the structures of the alveoli that help its gaseous exchange?
. Walls are very thin (one cell thick) -> short diffusion pathway
. Extensive capillary network -> excellent blood supply
. Large surface area -> millions of alveoli in each lung allowing for a greater uptake of oxygen
What is the mechanics of breathing?
Due to air moving from an area of high pressure to an area of low pressure via diffusion, the greater the difference in pressure, the faster the air will flow
During inspiration what should the pressure gradient be like between the lungs and the atmosphere?
The pressure should be lower in the lungs than in the atmosphere
During expiration what should the pressure gradient be like between the lungs and the atmosphere?
The pressure should be higher in the lungs than the atmosphere
What will increasing the volume of the thoracic cavity do the pressure in the lungs?
It reduces the pressure in the lungs
What will decreasing the volume of the thoracic cavity do to the pressure in the lungs?
It increases the pressure in the lungs
During inspiration at rest what muscles are used?
Diaphragm and external intercostals
During inspiration during exercise what muscles are used?
Diaphragm
External intercostals
Sternocleidomastoid
Scalenes
Pectoralis major
During expiration at rest what muscles are used?
It is passive so diaphragm is used whereas the external intercostals just relax
During expiration during exercise what muscles are used?
Internal intercostals and abdominals
What happens when air is taken in?
. Rib cage moves upwards and outwards
. Diaphragm contracts and is pulled flat
What happens when air is forced out?
. Rib cage falls
. Diaphragm relaxes and rises to dome shaped position
What is tidal volume?
Volume of air breathed in or out per breath
What is the inspiration reserve volume (IRV)?
Volume of air that can be forcibly inspired after a normal breath
What is the expiratory reserve volume (ERV)?
Volume of air that can be forcibly expired after a normal breath
What is residual volume?
The amount of air that remains in the lungs after a maximal expiration
What is 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
What happens to the tidal volume during exercise?
Increases
What happens to the inspiratory reserve volume during exercise?
Decreases
What happens to the expiratory reserve volume during exercise?
Slightly decreases
What happens to the residual volume during exercise?
Remains the same
What happens to the minute ventilation during exercise?
Big increase
What is partial pressure?
The pressure exerted by an individual gas when it exists within a mixture of gases
What is diffusion?
The movement of gas molecules from an area of high concentration to an area of low concentration
What should happen to the partial pressure of oxygen as it moves from the alveoli, to the blood and then to the muscle.
The partial pressure of oxygen needs to be successively lower
Why is the partial pressure of oxygen greater in the alveoli then the blood?
Oxygen is removed by the working muscles from the blood and so the concentration of oxygen becomes lower in the blood and so does it’s partial pressure
How does gaseous exchange occur at the alveoli?
Due to the concentration gradient between the alveoli and the blood vessel in partial pressure, the oxygen diffuses from the alveoli to the blood vessel so that it can become equal
How does gaseous exchange take place in the muscles?
The partial pressure of oxygen has to be lower at tissues than in the blood for diffusion to occur. Capillary membranes surrounding the muscle has a partial pressure of 40mmHg and 100mmHg in the blood. This lower partial pressure allows oxygen to diffuse from the blood into the muscle until equilibrium is reached. Conversely, the partial pressure of carbon dioxide is lower in the blood (40mmHg) than in the tissues (46mmHg) so again, diffusion occurs and carbon dioxide moves into the blood to be transported to the lungs.
What three factors are involved in the regulation of pulmonary ventilation during exercise?
. Neural control
. Chemical control
. Hormonal control
What is neural control?
Involves the brain and the nervous system
What is chemical control?
Concerned with blood acidity
What do both neural and chemical control work towards and how?
They work towards the control of breathing. When blood acidity is too high the brain is informed and it sends impulses through the nervous system to increase breathing.
What does hormonal control do?
Prior to exercise, the brain sends impulses to the renal glands which respond and pump adrenaline into the blood in anticipation of the increased need for oxygen and carbon dioxide exchange.
What effect does smoking have on the respiratory system?
. Irritation of the trachea and bronchi
. Reduces lung function
. Damages cells lining of trachea, bronchi and bronchioles
. Cilia damaged so leads to excess mucus build up in lung passages
. Damage alveoli as walls break down and join together reducing gaseous exchange due to larger air spaces than usual
. Increase risk of COPD
