Bioenergetics 1 - Life & Energy (incl. Bomb Calorimeter) Flashcards
Ultimately, why do we breathe?
So that we can produce energy in the form of ATP!
EVERY cell has the capacity for self-………… and self-…………… .
Replication, assembly.
What is the bioenergetics definition of energy?
How living systems capture, transform and use energy to perform work and stay alive.
Name some forms of biological work.
Synthetic, mechanical, concentration (e.g. active transport), electrical, heat, bioluminescent.
Hydrocarbons + oxygen =
CH4 + 2O2 =
Water + carbon dioxide + energy.
H2O + CO2 + energy.
Dietery fuel / carbohydrates and lipids + oxygen =
C6H12O6 + O2 =
Carbon dioxide + water + energy.
6CO2 + H2O + energy.
How would a biochemist define energy?
Usually, as the chemica energy that is exchanged in a reaction, e.g.:
ATP to ADP, NADH to NAD+ or Glucose to CO2 and H2O.
What is the activation energy of a reaction?
How much energy is required for the reaction to take place.
What effect does an catalyst have on the activation energy of a reaction?
A catalyst lowers the activation energy of a reaction.
Are living creatures efficient in their chemical reactions?
No!
True or false? Reactions in living creatures always have a start and an end point.
False.
Why is non-equilibrium thermodynamics used in living organisms?
Non-equilibrium thermodynamics are used in living organisms because they are very inefficient and the reactions do not have a start and end point.
Why can’t equilibrium thermodynamics be used in living organisms?
Reactions in living organisms do not have start and end points.
Define a ‘system’.
The matter within a defined region of space.
What is an open system? Give an example.
In open systems, matter AND energy can be exchanged between the system and its surroundings.
e.g. ocean.
What is a closed system? Give an example.
In a closed system, energy can enter and leave the system into the surroundings, but matter is trapped within the system.
e.g. greenhouse.
What is an isolated system? Give an example.
An isolated system is one where both energy and matter are trapped inside the system and cannot leave.
e.g. gas cylinder.
What is the concept of equilibrium thermodynamics?
‘Man-made machines are devices which allow energy to be transformed from one type to another’.
What is this concept called?:
‘Man-made machines are devices which allow energy to be transformed from one type to another’.
Equilibrium thermodynamics.
What is the First Law of Thermodynamics?
Energy within a system is conserved, it can be converted from one form to another but it cannot be created or destroyed.
If a reaction occurs in a well-insulated container, there is no ……………… exchange.
If a piston is prevented from moving, there is no …………….. done.
This is the principle of the …………… …………….. .
Heat, work, bomb calorimeter.
ΔE = Q-W.
What does this reaction show?
Change in energy = heat added to the system - work done.
If there is no heat exchange and Q = 0. What does ΔE = ?
-W.
If no work is done and W=0, what is ΔE?
Q.
