2.3 Metabolic Rate Flashcards
what is metabolic rate?
the rate of consumption of energy by an organism
what is the respiration word equation?
glucose + oxygen — — —> energy + carbon dioxide + water
how can metabolic rate be measured?
- by measuring heat production
- by measuring oxygen consumption
- by measuring carbon dioxide production
describe ‘how metabolic rate can be measured using a calorimeter’
Heat generated by the organism causes a rise in temperature of the water in the pipe.
By measuring the temperature of the water entering and leaving the calorimeter for a certain time, the organism’s metabolic rate can be calculated.
describe ‘how metabolic rat can be measured using a respirometer’
Differences in oxygen concentration, carbon dioxide concentration and temperature between the air entering and the air leaving the respirometer are detected by probes.
what is Basal Metabolic Rate (BMR0?
the minimum rate of energy release needed y an endothermic to maintain essential processes
name some essential processes and endotherm must maintain
- muscle contraction (breathing and heartbeat)
- osmoregulation (water control)
- thermoregulation (maintain core body temperature)
- active transport
describe ‘the term oxygen delivery’
Oxygen is used up the most during aerobic respiration so high metabolic rates require more efficient delivery of oxygen to cells. This is achieved by the circulatory systems.
what is the function of heart valves?
to prevent the back flow of blood
why is the wall of the left ventricle thicker than the wall of the right ventricle?
the left ventricle has to pump blood around the whole body whereas the right ventricle only has to pump blood around the lungs
describe ‘a single type of circulation)
e.g. fish
- blood passes through the heart once in each complete circuit
- bloods flows to the gills at high pressure but a drop in pressure means blood flows to the body tissues at a lower pressure, this is inefficient
- 2 Chambers — 1 Atrium and 1 Ventricle
describe ‘a double (incomplete) type of circulation’
e.g. reptiles and amphibians
- blood passes through the heart twice in each complete circuit
- some mixing of oxygenated and deoxygenated blood in each ventricle
- more efficient than single circulation, blood flows to tissues at high pressure
- 3 Chambers — 2 Atria and 1 Ventricle
describe ‘a double (complete) type of circulation’
e.g. mammals and birds
- blood passes through the heart twice in each complete circuit
- no mixing of oxygenated and deoxygenated blood in each ventricle
- more advanced and efficient circulatory system
- 4 Chambers —2 Atria and 2 Ventricles
why do mammals and birds need a more efficient circulatory system than other vertebrates?
they have higher metabolic rates (e.g. birds to fly)
