Lecture 3

Question 1

when life generates order, does entropy increase or decrease?

Answer 1

decrease

Question 2

where is most of life’s energy from ?

Answer 2

the sun

Question 3

does driving away from equilibrium increase or decrease entropy?

Answer 3

increase

Question 4

why is the human body warm?

Answer 4

due to the mitochondria

Question 5

what is used to drive all processes in humans?

Answer 5

cellular respiration

Question 6

how to autotrophs create energy? (what energy do they capture and what energy do they make)

Answer 6

autotrophs (photoautotrophs) capture electromagnetic energy of light and convert into chemical energy

Question 7

how to heterotrophs/herbivores create energy? (what energy do they capture and what energy do they make)

Answer 7

heterotrophs/herbivores consume, use, store chemical energy and pass energy onto carnivores

Question 8

how is excess fuel stored?

Answer 8

excess fuel is stored as glycogen and fat - provide energy when fasting

Question 9

what are the four main fuel stores in the body? and what percentage do they make up

Answer 9

muscle glycogen - 0.4%
liver glycogen - 0.2%
fat - 85%
protein - 4.5%

Question 10

what type of tissue can release things into blood?

Answer 10

adipose tissue (fat tissue)

Question 11

can muscle release things into blood or not?

Answer 11

no

Question 12

what 3 things sources of fuel contribute to ATP synthesis?

Answer 12

carbohydrate, fat, protein

Question 13

1st law of thermodynamics

Answer 13

1) Energy is not created or destroyed, it just changes form

Question 14

2nd law of thermodynamics

Answer 14

2) The overall entropy of the Universe is increasing

Question 15

equation for 1st law of thermodynamics

Answer 15

ΔH = q + w
change in enthalpy = heat + work done

Question 16

what does each part of this equation mean:
ΔG = ΔH - TΔS

Answer 16

G = Gibbs free energy - changes in energy for a given reaction

H = enthalpy = total energy

S = entropy

Question 17

what type of reactions does a high negative ΔG make?

Answer 17

unfavourable reactions (spontaneous)

Question 18

what is the ATP-ADP cycle?
(input, equation, output)

Answer 18

energy from catabolism (CO2 and O2)
—>
ATP + H2O => ADP + Pi
–> Energy for cellular work

Question 19

why is a negative ΔGo’ value for ATP hydrolysis important?

Answer 19

overall release of energy on hydrolysis is exothermic reaction (outwards flow of energy)

Question 20

how is free energy from ATP hydrolysis used?

Answer 20

the energy released is used to power many energy-requiring cellular reactions