The respiratory system Flashcards
1
Q
What is the definition of breathing?
A
- Breathing involves the movement of air into and out of the lungs, facilitated by various respiratory muscles
2
Q
What is the diaphragm?
A
- The diaphragm is the primary muscle involved in inspiration and expiration
3
Q
What is the function of the diaphragm at rest?
A
- During inspiration at rest, the diaphragm contracts and moves downwards, increasing the volume of the thoracic cavity and lowering the pressure inside of the lungs. This creates a pressure difference between the lungs and the external environment which draws air into the lungs
- During expiration at rest, the diaphragm relaxes and domes upwards, decreasing the volume of the thoracic cavity and increasing the pressure inside of the lungs. This creates a pressure difference between the lungs and the external environment which forces air out of the lungs.
4
Q
What is the function of the diaphragm during exercise?
A
- During inspiration while exercising, the diaphragm works harder to supply more oxygen into the body. It contracts more forcefully to increase the volume and decrease the pressure of the thoracic cavity. This pressure difference draws air into the lungs.
- During expiration while exercising, the diaphragm continues to relax and dome upwards, but causes expiration to become more forceful to expel air out quickly. This is especially useful is the body is producing excess carbon dioxide.
5
Q
What is the function of the diaphragm during recovery?
A
- During inspiration while recovering, the diaphragm gradually returns to its normal rhythm, but continues to support deep breaths if it is necessary to restore oxygen levels.
- During expiration while recovering, the diaphragm relaxes and the body returns to its normal its normal resting ventilation rate.
6
Q
What are the external intercostals?
A
- The external intercostal muscles are located between the ribs
- They help to expand the thoracic cavity during inspiration by elevating the ribs
7
Q
What is the function of the external intercostals at rest?
A
- During inspiration at rest, the external intercostals contract, pulling the ribs upwards and outwards. This increases the volume of the thoracic cavity and decreases the pressure inside of the thoracic cavity which aids in the intake of air.
- During expiration at rest, the external intercostals are relaxed and the ribs return to their resting position due to elastic recoil
8
Q
What is the function of the external intercostals during exercise?
A
- During inspiration while exercising, the external intercostals contract more forcefully, which allows for a greater expansion of the rib cage to increase the volume of the thoracic cavity. This facilitates faster and deeper breathing.
- During expiration while exercising, the external intercostals are less involved as the internal intercostals take over to expel air out more forcefully.
9
Q
What is the function of the external intercostals during recovery?
A
- During inspiration while recovering, the external intercostal muscles aid with continued deep breathing of the body is recovering from intense exercise.
- During expiration while recovering, the external intercostals relax and the breathing rate returns to its normal resting rate.
10
Q
What are the sternocleidomastoids?
A
- The sternocleidomastoids are muscles located in the neck
- They lift the sternum and clavicle during forced inspiration
11
Q
What is the function of the sternocleidomastoids at rest?
A
- During inspiration at rest, the sternocleidomastoids are not significantly active. This is because breathing is a passive process.
- During expiration at rest, the sternocleidomastoids do not play a major role.
12
Q
What is the function of the sternocleidomastoids during exercise?
A
- During inspiration while intensely exercising, the sternocleidomastoids contract to lift the upper chest, further increasing the volume of the thoracic cavity to allow for deep and rapid breathing.
- During expiration while intensely exercising, the sternocleidomastoids may assist is forced expiration.
13
Q
What is the function of the sternocleidomastoids during recovery?
A
- During inspiration while recovering, the sternocleidomastoids help the body restore deep and efficient breathing after exercise.
- During expiration while recovering, the sternocleidomastoids are not involved during normal recovery breathing.
14
Q
What is the pectoralis minor?
A
- The pectoralis minor is a muscle located in the chest
- It assists in elevating the ribs during deep breathing
15
Q
What is the function of the pectoralis minor at rest?
A
- During inspiration at rest, the pectoralis minor does not contribute to breathing.
- During expiration at rest, the pectoralis minor is relaxed and does not contribute to normal expiration.
16
Q
What is the function of the pectoralis minor during exercise?
A
- During inspiration while exercising, the pectoralis minor contracts to elevate the ribs, helping to expand the thoracic cavity to allow for deep breathing.
- During expiration while exercising, the pectoralis minor is not typically active.
17
Q
What is the function of the pectoralis minor during recovery?
A
- During inspiration while recovering, the pectoralis minor assist in deep recovery breaths after strenuous exercise, helping to return oxygen levels to normal.
- During expiration while recovering, the pectoralis minor is not typically engaged.
18
Q
What are the scalene muscles?
A
- The scalene muscles are located in the neck
- They assist in elevating the first and second ribs during forced inspiration
19
Q
What is the function of the scalene muscles at rest?
A
- During inspiration at rest, the scalene muscles are not significantly active.
- During expiration at rest, these muscles are relaxed during passive expiration.
20
Q
What is the function of the scalene muscles during exercise?
A
- During inspiration while exercising, the scalene muscles contract to elevate the first and second ribs, helping to expand the thoracic cavity to allow for deeper breaths and a larger volume of air intake.
- During expiration while exercising, the scalene muscles do not contribute significantly, except during forced expiration during intense exercise.
21
Q
What is the function of the scalene muscles during recovery?
A
- During inspiration while recovering, the scalene muscles assist in deep breathing.
- During expiration while recovering, these muscles are not involved.
22
Q
What are the internal intercostals?
A
- The internal intercostals are located between the ribs
- They assist in forced expiration by pulling the ribs downward and inward
23
Q
What is the function of the internal intercostals at rest?
A
- During inspiration at rest, the internal intercostals are not significantly active.
- During expiration at rest, the internal intercostals are relaxed.
24
Q
What is the function of the internal intercostals during exercise?
A
- During inspiration while exercising, the internal intercostals are not heavily involved unless forced inspiration is required.
- During expiration while exercising, the internal intercostals contract during forced expiration, helping to push air out more rapidly. This is especially useful during intense physical activity when air needs to be expired quickly.
25
Q
What is the function of the internal intercostals during recovery?
A
- During inspiration while recovering, the internal intercostals are not involved.
- During expiration while recovering, the internal intercostals may help with forced exhalation if the body is working to return to normal breathing levels after strenuous exercise.
26
Q
What is the rectus abdominis?
A
- The rectus abdominis is a muscle in the abdomen
- It helps with forced expiration by compressing the abdominal contents and pushing the diaphragm upwards
27
Q
What is the function of the rectus abdominis at rest?
A
- During inspiration at rest, the rectus abdominis is relaxed.
- During expiration at rest, the rectus abdominus is not active.
28
Q
What is the function of the rectus abdominis during exercise?
A
- During inspiration while exercising, the rectus abdominis does not significantly contribute.
- During expiration while exercising, the rectus abdominus contracts, helping to force air out of the lungs by pushing the diaphragm upward and reducing the volume of the thoracic cavity. This is helpful during intense exercise or forced expiration.
29
Q
What is the function of the rectus abdominis during recovery?
A
- During inspiration while recovering, the rectus abdominis does not contribute.
- During expiration while recovering, the rectus abdominis may help during forceful expiration, helping to expel residual air and assist in returning back to normal breathing levels.
30
Q
What are the average breathing volumes of an untrained individual during rest, sub-maximal intensity and maximal intensity?
A
31
Q
What are the average breathing volumes of a trained individual during rest, sub-maximal intensity and maximal intensity?
A
32
Q
What is breathing rate?
A
- Breathing rate (f) is the number of breaths taken per minute
- It is measured in breaths / min
33
Q
What is tidal volume?
A
- Tidal volume (TV) is the volume of air inspired or expired per breath
- It is measured in mL or L
34
Q
What is minute ventilation?
A
- Minute ventilation (VE) is the volume of air inspired or expired per minute
- It is measured in L/min
- Minute ventilation = tidal volume x breathing rate
35
Q
What is inspiratory reserve volume?
A
- Inspiratory reserve volume (IRV) is the maximum air that can be forcibly inhaled after a normal inspiration
- It is measured in mL or L
36
Q
What is expiratory reserve volume?
A
- Expiratory reserve volume (ERV) is the maximum air that can be forcibly exhaled after a normal expiration
- It is measured in mL or L
37
Q
What is residual volume?
A
- Residual volume (RV) is the air remaining in the lungs after maximum expiration
- It is measured in mL or L
38
Q
What is vital capacity?
A
- Vital capacity (VC) is the maximum air forcibly exhaled after maximal inhalation
- It is measured in mL or L
- Vital capacity = Tidal volume + Inspiratory reserve volume + expiratory reserve volume
39
Q
What is total lung volume?
A
- Total lung volume (TLV) is the total volume of air in lungs after maximum inspiration
- It is measured in mL or L
- Total lung volume = Vital capacity + residual volume
40
Q
Diagram of a spirogram
A
41
Q
What is the role of neural control when regulating breathing?
A
- Chemoreceptors in the aortic arch and carotid bodies detect rising carbon dioxide levels or decreased oxygen levels and increase the depth and rate of breathing
- Thermoreceptors detect an increase in body temperature which stimulates an increase in breathing rate
- Mechanoreceptors detect movement in muscles and joints which stimulates faster breathing
- Stretch receptors in the lungs prevents the over-inflation by sending feedback to reduce the inhalation effort
42
Q
What is the role of the Hering-Breuer reflex when regulating breathing?
A
- The Hering-Breuer protective reflex is triggered by lung stretch receptors to prevent over-inflation
- When lungs are stretched too fair, inspiration is inhibited to allow expiration
43
Q
What is the role of hormonal control when regulating breathing?
A
- Adrenaline is released during exercise and stimulates the breathing rate and depth of breathing to increase, allowing more oxygen to be supplied to muscles and carbon dioxide to be removed faster
44
Q
What is the role of the respiratory control centre when regulating breathing?
A
- The respiratory control centre (RCC) is located in the medulla oblongata
- It has inspiratory centres which stimulates the diaphragm and external intercostal muscles
- It has expiratory centres which becomes active during forced expiration, causing the internal intercostals and rectus abdominis to begin working
45
Q
What is the role of the automatic nervous system when regulating breathing?
A
- The sympathetic nervous system stimulates increased breathing during exercise
- The parasympathetic nervous system promotes relaxation and reduced breathing during rest and recovery
46
Q
Table showing breathing volumes before exercise, during exercise and during recovery
A
47
Q
How do breathing volumes change with long-term training?
A
48
Q
What is gaseous exchange and where does it occur?
A
- Gaseous exchange is the process where oxygen moves into the blood and carbon dioxide moves out of the blood by diffusion
- It occurs in the lungs between the alveoli and capillaries and in the muscles between the capillaries and muscle cells
49
Q
What is partial pressure?
A
- Partial pressure (pO₂ / pCO₂) is the pressure exerted by a specific gas within a mixture
50
Q
What is the diffusion gradient?
A
- The diffusion gradient is the difference in partial pressure between two areas that causes gas to move from an area of high to an area of low pressure
51
Q
What is haemoglobin?
A
- Haemoglobin (Hb) is a protein in red blood cells that binds to oxygen to form oxyhaemoglobin (HbO₂)
52
Q
What is myoglobin?
A
- Myoglobin is a protein in muscles that stores oxygen and has a higher affinity for oxygen that haemoglobin
53
Q
What are alveoli?
A
- Alveoli are tiny air sacs in the lungs where gaseous exchange takes place
54
Q
What are capillaries?
A
- Capillaries are very thin blood vessels that allow the exchange of gases and nutrients with tissues
55
Q
How do partial pressure differences, alveoli, haemoglobin, blood capillaries, and the diffusion gradient work together to enable gaseous exchange in the lungs at rest?
A
- Partial pressures: Oxygen (PO₂) is high in the alveoli and low in the blood. Carbon dioxide (PCO₂) is low in the alveoli and high in the blood
- Alveoli: The oxygen from the alveoli diffuses into the blood and the carbon dioxide from the blood diffuses into the alveoli
- Haemoglobin and blood capillaries: Haemoglobin in red blood cells binds with oxygen to form oxyhaemoglobin and carries it through the blood stream. The blood returning from the muscles is deoxygenated and releases carbon dioxide to be exhaled
- Diffusion gradient: Oxygen diffuses from the higher concentration in the alveoli to the lower concentration in the blood. Carbon dioxide diffuses in the opposite direction
56
Q
How do partial pressure differences, alveoli, haemoglobin, blood capillaries, and the diffusion gradient work together to enable gaseous exchange in the lungs during exercise?
A
- Partial pressures: Oxygen (PO₂) is still high in the alveoli, but the blood has a lower PO₂ due to increased oxygen consumption in the muscles. Carbon dioxide (PCO₂) is higher in the blood due to the increased production of CO₂ by the muscles during exercise and lower in the alveoli
- Alveoli: Oxygen still diffuses into the blood, but the increased CO₂ in the blood means that the carbon dioxide diffuses into the alveoli to be exhaled
- Haemoglobin and blood capillaries: Haemoglobin releases oxygen more readily to the blood due to the increased need for oxygen in the muscles. Carbon dioxide is picked up by the blood from muscle tissues and transported to the lungs
- Diffusion gradient: The increased carbon dioxide in the blood lowers the blood pH, facilitating the release of oxygen from haemoglobin (Bohr effect)
57
Q
How do partial pressure differences, alveoli, haemoglobin, blood capillaries, and the diffusion gradient work together to enable gaseous exchange in the lungs during recovery?
A
- Partial pressures: Oxygen levels in the blood are still lower than at rest due to ongoing muscle recovery processes. Carbon dioxide levels in the blood are still elevated as metabolic processes return to normal
- Alveoli: Oxygen continues to diffuse into the blood and carbon dioxide is removed as blood returns to the lungs
- Haemoglobin and blood capillaries: Haemoglobin continues to release oxygen to the tissues and carbon dioxide is removed
- Diffusion gradient: As oxygen levels slowly return to normal and carbon dioxide is removed from the blood, the diffusion gradients gradually normalise.
58
Q
How do partial pressure differences, myoglobin, haemoglobin, blood capillaries, and the diffusion gradient work together to enable gaseous exchange in the muscles at rest?
A
- Partial pressures: Oxygen is high in the blood and lower in muscle cells. Carbon dioxide is low in the blood and high in muscle cells due to cellular respiration
- Myoglobin: Myoglobin in muscle cells stores oxygen and releases it when needed, ensuring muscle tissues are supplied with sufficient oxygen
- Haemoglobin and blood capillaries: Haemoglobin carries oxygen from the lungs to the muscles, where it is released into the muscle cells. Carbon dioxide diffuses from the muscle cells into the blood
- Diffusion gradient: Oxygen diffuses from the blood (higher PO₂) to the muscle cells (lower PO₂) and CO₂ diffused from the muscle cells (higher PCO₂) into the blood (lower PCO₂)
59
Q
How do partial pressure differences, myoglobin, haemoglobin, blood capillaries, and the diffusion gradient work together to enable gaseous exchange in the muscles during exercise?
A
- Partial pressures: Oxygen is lower in the muscle cells compared to the blood due to increased demand for oxygen. Carbon dioxide is higher in the muscle cells due to increased production of CO₂ during exercise
- Myoglobin: Myoglobin releases stored oxygen to the muscle cells, helping meet the increased oxygen demand
- Haemoglobin and blood capillaries: Haemoglobin releases more oxygen to the muscles due to the decreased PO₂ in the tissues and more CO₂ is picked up from the muscles to be transported back to the lungs
Diffusion gradients: The PO₂ in the blood decreases as muscles use more oxygen, and the PCO₂ increases as CO₂ is produced. This strengthens the gradient for oxygen to diffuse into muscle cells and CO₂ to diffuse into the blood
60
Q
How do partial pressure differences, myoglobin, haemoglobin, blood capillaries and the diffusion gradient work together to enable gaseous exchange in the muscles during recovery?
A
- Partial pressures: Oxygen demand in the muscles is still high initially as the body works to recover, but this gradually returns to normal. Carbon dioxide levels are still elevated as muscles continue to clear waste products and return to a resting state
- Myoglobin: Myoglobin continues to release oxygen to the muscle cells, helping the muscles replenish oxygen stores and remove carbon dioxide
- Haemoglobin and blood capillaries: Haemoglobin continues to transport oxygen to the muscles, and carbon dioxide is removed from the blood and transport back to the lungs
- Diffusion gradients: The diffusion gradients slowly return to their resting state as oxygen demand decreases, and carbon dioxide is cleared from the blood
