Respiration Flashcards
For strenuous exercises, 20% of energy comes from aerobic respiration whereas 80% of energy comes from anaerobic respirations.
For less strenuous exercises, 80% of energy comes from aerobic respiration whereas 20% of energy comes from anaerobic respirations.
Explain the statements [6]
Type of exercise with vigorous / less vigorous muscular contractions; with
higher / lower energy demand [1]
Aerobic respiration is insufficient / sufficient to release the energy to meet the
demand [1]
More / less compensation from anaerobic respiration to release energy to meet the energy demand resulting in more / less lactic acid production [1]
More / less oxygen debt to pay back to remove the lactic acid during post exercise [1]
Given that both a regular athlete and a normal individual carried out the same activity with the same intensity, compare the two individuals in terms of lactic acid production. Explain your answer. [4]
The regular athlete should have less lactic acid production than the normal individual [1]
Regular athlete has more efficient heart pumping action to transport more blood rich in oxygen and glucose to skeletal muscles per unit time. [1]
Increase aerobic respiration to release more energy in meeting the energy demand of the activity [1]
Less anaerobic respiration needed thus less lactic acid production for regular athlete than normal individual [1]
Explain why oxygen uptake remains high during post-exercise [4]
Repay oxygen debt in the form of lactic acid build up at start of exercise; Lactic acid transported to liver [1]
Post exercise oxygen uptake to oxidise some lactic acid to release E [1] Energy used to convert the remaining lactic acid to glucose [1]
Excess glucose to convert into glycogen to be stored in the liver or transported to muscles to store as glycogen in the muscles [1]
Compare and contrast between aerobic and anaerobic respirations in humans [4]
Similarity
Release energy
Require glucose as raw material
Require enzymatic reactions
Difference
Amount of E released is more for aerobic than anaerobic Aerobic requires O2 whereas anaerobic don’t need
Aerobic produces CO2 and water as products whereas anaerobic produce lactic acid.
Describe the adaptations of the alveoli / alveolus in gaseous exchange
Alveoli [4] *plural (any 4 pts)
Increase surface area for faster diffusion of gases
Rich in blood capillaries for faster rate of exchange of gases between blood and alveoli
Constant blood flow to maintain steep conc gradient of O2 and Co2 between blood and air in the alveoli for faster rate of diffusion
Each alveolus wall made of one layer of epithelial cells; shorter distance for faster diffusion of gases
Layer of moisture in each alveolus to dissolve the gases for diffusion
Alveolus [3] *singular
Wall made of one layer of epithelial cells; shorter distance for faster diffusion of gases
Layer of moisture to dissolve the gases for diffusion
Constant blood flow to maintain steep conc gradient of O2 and Co2 between blood
and air in the alveoli for faster rate of diffusion
Describe the mechanism of inhalation and the impact of a punctured lung on the
breathing process [6]
Mechanism
Diaphragm contracts and flattens down.
External intercostal muscles contract and internal intercostal muscles relax rib cage is raised upwards and outwards
Thoracic volume increases, pressure in the lung decreases to lower than outside environment, pressure difference cause air to draw into the lungs
Impact of punctured lung
Free exchange of air between external environ and inside thoracic cavity through the punctured opening
No pressure difference can be generated
No air will be forced into the lung for gaseous exchange. Lung collapse.
Describe and explain the effects of smoking on pregnant mothers [6]
Tobacco contain carbon monoxide which binds irreversibly to haemoglobin in red blood cells to form carboxyhaemoglobin [1] hence decreasing the oxygen carrying capacity of the red blood cells. [1] Developing fetus will have insufficient oxygen supply to release energy during aerobic respiration for cellular activities in normal development [1]
Tobacco also contains nicotine which can diffuse across the placenta to be passed to the fetus [1]. It will increase risks of blood clots forming and narrowing of blood vessels in the fetus, causing reduced blood supply [1] less transport of O2 and glucose for aerobic respiration to release energy for cellular activities in normal development. [1]
