Respiratory system Flashcards
For effective performance, games players require oxygen to be delivered to the muscles and carbon dioxide to be removed.
Explain how oxygen is taken up by haemoglobin from the lungs and released at the muscle site.
[3 marks]
- Forms oxyhaemoglobin / Hb O2
- At lungs – high partial pressure of O2 / blood – low partial pressure of O2.
- Haemoglobin becomes saturated.
- At muscles – low partial pressure of Oxygen / O2 / blood – high partial
pressure of O2. - Hence oxygen dissociates from haemoglobin.
- Mention of myoglobin.
Describe how an increase in carbon dioxide in the blood during exercise would lead to an increased breathing rate. [3 marks]
* Increased blood acidity/decreased blood pH. (1)
* Detected by chemoreceptors. (1)
* Impulse sent to the respiratory centre/medulla. (1)
* Increased impulses to respiratory muscles to contract faster. (1)
Accept named respiratory muscles including diaphragm/intercostal muscles/scalene/ sternocleidomastoid/pectorals/abdominals.
Accept any other appropriate description of how an increase in carbon dioxide in the blood during exercise would lead to an increased breathing rate.
Explain how and why a period of continuous exercise would impact the lung volumes in the graph above.
Tidal volume
Expiratory reserve volume
Residual volume
* (Tidal volume) would increase as performer needs more oxygen to working muscles (1)
* (Expiratory reserve volume) decreases due to the increase in tidal volume (1)
* (Residual volume) will stay the same as if it decreased the lungs would be at risk of collapse/not affected by continuous exercise (1)
Accept any other appropriate explanation of how and why a period of continuous exercise would impact the lung volumes in the graph.
The table below shows tidal volumes and respiratory rates when exercising at different intensities.
Calculate minute ventilation during medium intensity exercise. [total 2 marks]
Two marks for the correct answer with correct units: 60 l/min (2)
One mark for correct workings or correct answer without units: Respiratory Rate x Tidal Volume / 30 x 2 / 60 (1)
How does exercise affect the lung volumes labelled X and Y in the graph below.
A
X: Decreases Y: Decreases
B
X: Decreases Y: Stays the same
C
X: Stays the same Y: Decreases
D
X: Stays the same Y: Stays the same
B
Describe the process of gas exchange which occurs at a muscle.
[total 3 marks]
* Oxygen diffuses from the capillary to the muscle cells and carbon dioxide diffuses from the muscle cells to the capillary (1)
* Oxygen / carbon dioxide moves from areas of high concentration/partial pressure to areas of low concentration / partial pressure (1)
* Myoglobin transports and stores oxygen in the muscle / has a higher affinity to oxygen then haemoglobin / pulls more oxygen in to the muscle (1)
Accept any other appropriate description of how gas exchange occurs at a muscle.
Which one of these statements defines expiratory reserve volume?
A
Volume of air inspired and expired per breath.
B
Volume of air inspired and expired per minute.
C
Volume of air that can be forcibly expired after a normal breath.
D
Volume of air that remains in the lungs after expiration.
C
Smoking is a poor lifestyle choice because of the negative effect it can have on health and performance.
Identify one physiological effect of smoking on the respiratory system and explain its impact on performance in endurance events.
[total 4 marks]
AO1 (Physiological effects)
Carbon monoxide binds to haemoglobin rather than oxygen (1)
Nicotine constricts the bronchioles (1)
Damaged cilia (1)
Reduction in number / damaged alveoli (1)
Physiological effects must relate specifically to the respiratory system
Sub-max 1 mark
Award one mark for each of the following points.
AO2
Reduced gaseous exchange in the lungs / oxygen transport to the muscles (1)
AO3 (Impact on performance)
This decreases the athlete’s ability to utilise oxygen in energy production / work aerobically (1). This means they have less energy for their activity / slower time / fatigue quicker (due to working anaerobically) (1).
Accept other appropriate physiological effects of smoking on the respiratory system and explanations of the impact on performance in endurance events.
The diagram below shows the partial pressure of oxygen (pO2) and carbon dioxide (pCO2) in the alveoli and blood capillary.
Consider how oxygen and carbon dioxide move between the alveoli and the blood capillary. Refer to the diagram in your answer.
[Total 4 marks]
AO1
* By a process called diffusion which is the movement of gases from a high concentration / partial pressure to a low concentration / partial pressure (1)
AO2
Oxygen
* The partial pressure of oxygen is higher in the alveoli pO2 = 104 mmHg and lower in the blood pO2 = 40mmHg (1) and so moves / from the alveoli to the blood (1)
Carbon Dioxide
* The partial pressure of carbon dioxide is higher in the blood pCO2 = 46mmHg and lower in the alveoli pCO2 = 40mmHg (1) and so moves / diffuses from the blood into the alveoli (1) Accept any other suitable consideration of how oxygen and carbon dioxide move between the alveoli and blood capillary (1)
Max 4 marks
‘Tidal volume × respiratory frequency’ is an equation.
Which one of these physiological measures does the equation allow you to calculate?
A
Expiratory reserve volume
B
Inspiratory reserve volume
C
Minute ventilation
D
Residual volume
C
Describe how poor lifestyle choices may affect the respiratory system.
[Total 3 marks]
- Lack of exercise / poor diet – reduced cardiovascular endurance – inefficient gas exchange
- Smoking - increased breathlessness / damages cells lining trachea, bronchi and bronchioles
- Excess mucus - smoker’s cough
- Breaks down alveolar walls - reduces efficiency of gaseous exchange
- Oxygen transport affected - carbon monoxide from cigarettes combines with haemoglobin in red blood cells more readily than oxygen - reduces oxygen-carrying capacity of blood
- Reduced stamina / cardio-respiratory endurance
Evaluate the impact of long-term aerobic training and lifestyle choices on the respiratory system.
(Total 8 marks)
General points
- Improvements to efficiency of respiratory system after a few weeks of aerobic training
- Increased efficiency to take in / supply O2 to muscles
Effects of training
- Increased surface area of alveoli
- Increased capillary density around alveoli / muscle
- Increased a-VO2 difference
- Respiratory muscles (named - diaphragm, intercostals, sternocleidomastoid, scalenes, abdominals) strengthened
- Increased depth of breathing / decreased breath frequency
- Increased tidal volume / minute ventilation during maximal exercise
- Increased vital capacity / inspiratory / expiratory reserve volume
- Increased VO2 max
Smoking / oxygen transport
- Decreased efficiency of respiratory system to supply O2 to muscles
- Carbon monoxide reduces amount of O2 absorbed in blood
- Haemoglobin has greater affinity to CO than O2
AO2 Award up to three marks for:
- Greater amount of O2 diffused into blood / CO2 into alveoli
- Greater gaseous exchange / increase pulmonary diffusion
- Greater saturation of haemoglobin with oxygen
- Greater amount of O2 diffused into muscle / CO2 into blood
- Greater gaseous exchange / increased muscle and tissue diffusion
- Reduces or delays respiratory muscle fatigue
- Delays OBLA or lactate threshold
- Increased aerobic endurance
Effects of smoking
- Decreased gaseous exchange or diffusion gradient
- Increased likelihood of respiratory diseases / damage to respiratory structures
- Tar coats the airways / builds up in lungs and inhibits gaseous exchange
- Narrowing of air passages causing increase in respiratory resistance
AO3 Award up to three marks for:
- Aerobic exercise improves / smoking reduces aerobic endurance
- Types of aerobic training - continuous / altitude / fartlek
- Best type of training is one that will be maintained
- HIIT possibly best
Tidal volume and minute ventilation of a cyclist will vary at rest and during a race.
Define tidal volume and minute ventilation.
[total 2 marks]
Must state which term is being defined
- Tidal volume – Amount of air breathed in or out in one breath (1)
- Minute Ventilation – Amount of air breathed in or out per minute/tidal volume x number of breaths (1)
Accept other appropriate definition of tidal volume and minute ventilation.
Explain how the cyclists’ increase in minute ventilation allows them to maintain performance throughout the race.
[Total 3 marks]
AO3
- Increased oxygen exchange in the alveoli (1)
- Increased oxygen delivery to the working muscles (1)
- Working muscles are able to work aerobically/with oxygen (1)
- Less lactic acid produced (1)
- Increased rate of removal of carbon dioxide in the alveoli (1)
Max 3 marks
Identify which one of the following statements defines expiratory reserve volume.
A
The amount of air breathed in or out per breath
B
The amount of air left in the lungs after maximal expiration has occurred
C
The amount of air that can be forcibly expelled after a normal breath
D
The amount of air that can be forcibly inspired at the end of a breath
C
Gaseous exchange occurs between the capillaries and tissues and the capillaries and alveoli.
Outline how the following characteristics of capillaries allow for efficient gaseous exchange:
- one cell thick
- large surface area
- narrow diameter.
One cell thick:
Large surface area:
Narrow diameter:
(Total 3 marks)
A One cell thick – short route for diffusion
B Large surface area – contact area/opportunity/surfaces for diffusion
Accept description of diffusion
Do not accept bigger area / increased diffusion
C Narrow diameter – slow passage of red blood cells/single file
Accept alternative explanations
Explain how the body modifys our breathing rate when we exercise.
The chemoreceptors detect an increase in CO2 and blood acidity within our blood, the baroreceptors detect a change in blood pressure and the proprioceptors detect increase muscle movement.
An impulse is sent to the inspiratory part of the respiratory control centre (RCC) in the medulla oblongota. The RCC sends an increased impulse via the phrenic nerve, to stimulate the respiratory muscles (diaphragm/intercostal muscles/scalene/ sternocleidomastoid/pectorals) to contract faster.
Also, stretch receptors within the lungs send impulses to the expiratory part of the respiratory centre, this restricts the lungs from over inflating. The expiratory centre sends an impulse via the intercostal nerve to the expiratory muscles (abdominals and internal intercostal muscles) to regulate breathing.
The table below shows the partial pressure of oxygen (PO2) and carbon dioxide (PCO2) in a blood capillary and a muscle.
Using the table above, describe how oxygen and carbon dioxide move between the blood and the muscles.
[Total 4 marks]
A Process of diffusion – high to low concentrations/partial pressure (down a concentration gradient)
Oxygen
B Partial pressure/PO2/concentration higher in blood (100) and lower in muscle (40)
C Moves/diffuses from blood/capillary to muscle
Must state oxygen.
Carbon Dioxide
D Partial pressure/PCO2/concentration higher in muscle (46) and lower in blood (40)
E Moves/ diffuses from muscle to blood/capillary
Must state carbon dioxide.
Many athletes will use continuous training to maintain a good level of fitness.
The diagram below shows a spirometer trace of an athlete at rest.
Q1. identify the type of lung volumes A, B and C shown in the diagram above.
Q2. What effect does a continuous exercise session have on lung volumes B and C in the diagram above?
Volume B:
Volume C:
Q1. A Tidal (Volume)
B Expiratory Reserve (Volume)
C Residual (Volume)
do not accept any other terms
accept first answer only
Q2. Volume B (Expiratory Reserve Volume) Will Decrease / get smaller.
Volume C (Residual Volume) Will Stay the same / remain unchanged / no effect.
do not accept ‘get closer together’ as the question refers to the volume not the trace
While running, a performer will experience changes in lung volumes.
Complete the table below to show how the tidal volume, inspiratory reserve volumeand expiratory reserve volume change during exercise.
Tidal volume – increases
Inspiratory reserve volume – decreases
Expiratory reserve volume – decreases
Accept equivalents to increase and decrease
Explain how the gas exchange system operates at muscles.
[Total 4 marks]
Process of diffusion – high concentration / partial pressure to low / down a diffusion gradient
Diffusion explained
Requires thin / permeable membranes / short distance
Only if one or more of these present
High pO2 in blood / low pO2 in muscles and oxygen moves into muscles
Accept concentration as equiv to pO2
Accept capillaries, blood vessels, etc
Low pCO2 in blood / high pCO2 in muscles and carbon dioxide moves into blood
Accept concentration as equiv to pO2
Accept capillaries, blood vessels, etc
Oxygen into myoglobin / (disassociates) from haemoglobin
Carbon dioxide dissolves in plasma / combines with haemoglobin / forms bicarbonate ion
During a game of tennis, a player’s breathing rate may vary.
Explain how increases in levels of carbon dioxide and acidity in the blood cause breathing rate to rise.
[Total 3 marks]
Detected by chemoreceptors (in carotid arteries / aortic arch / medulla).
Equiv of detected required.
Nerve impulses / message to respiratory control centre in / medulla of brain.
Equiv of messages / information required – Do not accept RCC.
Nervous output to breathing muscles / via Phrenic / sympathetic nerve.
Equiv of connection to breathing muscles – Do not accept SNS.
Increased rate of contraction of diaphragm and intercostal muscles.
Increased / equiv required.
Breathing rate increases to get more oxygen into the blood. Gaseous exchange involves oxygen diffusing across membranes.
Identify the membranes involved in this diffusion and identify one characteristic of these membranes that allows diffusion to happen
[Total 2 marks]
Alveolar / muscle and capillary membranes identified.
Sub max 1 mark
Requires thin membranes / one cell thick.
Eq of thin required
Requires short distance between membranes / moist / (semi) permeable / short diffusion
pathway.
In order to make use of their stamina, footballers need to take in oxygen.
The figure below shows values for the partial pressure of oxygen and carbon dioxide at two different locations in one gas exchange system.
Use the information in the figure above to explain how oxygen and carbon dioxide move between the two locations.
[total 3 marks]
The alveoli provide the lungs with a large surface area for diffusion.
Name two other structural features of the lungs that assist diffusion.
[total 2 marks]
(i) 3 marks for 3 of :
Process of diffusion – high to low concentrations / down a concentration
gradient / partial pressures / pO2.
Diffusion named and explained.
Some detail of differences shown in the figure.
Oxygen partial pressure / pO2 higher in alveoli (104) / lower in capillary (40)
OR Carbon dioxide partial pressure / pCO2 lower in alveoli (40) / higher in
capillary (46).
Gases move – oxygen from alveoli to capillary and carbon dioxide from
capillary to alveoli.
Identifying direction of movement of both gases.
Accept blood as alternative to capillary and lungs for alveoli.
(ii) 2 marks for 2 of :
Large blood supply.
Accepts lots of capillaries.
Thin / semi-permeable membrane for diffusion / one cell thick / walls are thin.
Do not accept capillary on own.
Accept named membrane (alveolar / capillary).
Short distance for diffusion.
Accept short diffusion pathway.
Layer of moisture.
Accept moist.
Slower blood flow / transit time.
