Lab Legends
He invented doubly labeled water
Lifson
The two energetically costliest organs
Liver and brain
Running a mile costs about the same calories whether you jog or sprint
True
The hydrogen isotope with one neutron.
Deuterium
What was the term coined "the essential stuff in combustible material that made it flammable and was released during combustion?"
Phlogiston
He discovered oxygen in 1774
Priestley
This essential organ burns about 80 kcal per day
Lungs
Small animals burn more energy per pound than large animals.
True, Kleiber's law
The oxygen isotope with eight protons and ten neutrons.
oxygen 18
The two isotopes of doubly labeled water
Deuterium and oxygen-18
His 1930s law says metabolic rate scales with mass to the 3/4 power.
Kleiber
We get approximately this many heartbeats before we die
1 billion
Walking is always cheaper per mile than running
False
Oxygen leaves the body as water and X, what is X
CO2
The respiratory quotient (CO₂ out ÷ O₂ in) when burning fat.
0.7
His "rate of living" theory said animals die after using up a lifetime energy allotment.
Rubner
5 mph
A skeleton (bone) burns more calories than skin
False, bone burns almost nothing, but skin burns about 30 kcal per day
Total CO₂ production is converted into this unit of energy.
Kcal
The respiratory quotient (CO₂ out ÷ O₂ in) when burning carbs.
1.0
In the 1950s he proposed the free radical theory of aging
Harman
The brain is about 2% of body weight. It burns about this share of resting energy.
20%
Heart rates match cellular metabolic rates across species
True, smaller species have both a higher heart rate and metabolic rate
Why does oxygen-18 leave the body faster than deuterium?
Oxygen exits as both water and CO₂, while hydrogen leaves only as water.
Difference between BMR and RMR
BMR, early morning, lying down, awake but calm, after no food for about six hours
RMR–Rate if any of above conditions are not met, a more ambiguous version