2.3 Metabolic Rate Flashcards
Define ‘Metabolic Rate’
Quantity of energy used in a given period of time
What three things can be used to measure metabolic rate?
Oxygen consumption
Carbon Dioxide output
Heat energy output
Describe a ‘Respirometer’
Sealed unit with a known volume of air
Contains NaOH to absorb Co2
Organism breathes and uses up oxygen, and releases Co2
Total volume of air decreases
Coloured liquid in capillary tube moves upwards to fill space
What is ‘Basal Metabolic Rate’?
Metabolic rate at rest
How can Oxygen consumption be measured?
Respirometer
How can Carbon Dioxide Output be monitored?
CO2 monitors
How can heat energy be monitored?
Thermometer
What does high metabolic rate require?
Efficient delivery of Oxygen to cells
Describe the circulatory systems of mammals
Complete Double
Describe the heart structure of fish
1 atrium, 1 ventricle
Describe the gas exchange system in birds
Very efficient
Parabronchi, keeps air flowing in one direction
Able to extract more oxygen
Fresh air to posterior air sac
Passes through parabronchi to front air sac (stale)
Describe the circulatory system of amphibians
Incomplete Double
Describe the heart structure of reptiles
2 atrium
1 ventricle
What minimises the mixing of blood in amphibians/reptiles?
Timings of contractions of hearts
Describe the circulatory system of fish
Complete Single
Describe the heart structure of mammals and birds
2 atria, 2 ventricles
Describe a disadvantage of the fish circulation system
Loss of pressure as blood passes through gills
Describe a feature of reptile and amphibian circulation
Mixing of oxygenated and deoxygenated blood
What are two advantages of the mammal circulation system?
- Pressure is maintained
- No mixing of different types of bloods
Describe the amphibian gas exchange system
Buccal Cavity - before the lung, forces air into the lung
Exchange gases through the moist skin
Describe the similarities in reptile/mammalian gas exchange systems
Both have a highly branched system containing air sacs
What is an advantage of the parabronchi gas exchange system>
- Able to extract more oxygen
- Keep air flowing in one direction
Why do birds require an efficient delivery of oxygen to cells?
Because they have a high metabolic rate due to lots of flying and activity during the day
Describe a human physiological adaptation to high oxygen niches
- Increased red blood cells
- Increased haemoglobin
- Increased breathing rate
What do the adaptations of humans at high altitudes allow for?
Increased oxygen carrying capacity of the blood, to maintain high metabolic rate needed
Describe a deep water physiological adaption
Seals
- Slow down their heart rate
- Collapse their lungs
Why do seals slow down their heart rate when going into deep water?
To conserve oxygen and allow them to stay submerged for longer periods of times
Why do seals collapse their lungs when diving?
Decrease their buoyancy allowing them to sink faster, conserving energy for hunting
What is VO2 Max?
Maximum Oxygen Uptake during strenuous exercise
How can VO2Max be used as a measure of human fitness?
Higher the V02 max - fitter the individual
V02 Max is reached when oxygen uptake stays steady even when workload increases
