Bioenergetics 1 - 2020 Flashcards
What are the two main types of energy?
Potential energy and kinetic energy
Potential energy is stored energy, while kinetic energy is energy in motion.
What is potential energy?
Bound in a specific form
It can be harnessed for biosynthesis by joining individual atoms.
What is kinetic energy?
Energy in motion
It results from the harnessing of potential energy.
Name the forms of energy.
- Chemical
- Mechanical
- Heat
- Light
- Electric
- Nuclear
- Biologic Work
Each form plays a different role in biological processes.
What type of work is associated with muscle contraction?
Mechanical work
This is one aspect of biologic work in living organisms.
What does active transport refer to?
Transport work
Active transport requires energy to move substances against their concentration gradient.
What is the First Law of Thermodynamics?
Energy cannot be created or destroyed, only transformed
This law illustrates conservation of energy in biological systems.
What happens to energy during transformations?
It includes the release of waste heat
Energy transformations are never 100% efficient.
What is entropy?
Measure of disorder or randomness
Entropy increases in the universe with energy transformations.
How does life relate to entropy?
Life involves complexity and organization, decreasing local entropy
This contrasts with the general increase in entropy in the universe.
What is Gibbs Free Energy?
Energy that can be used or ‘harvested’ by an organism
It is calculated using the equation H = G + T x S.
What indicates spontaneity in a process?
Changes in Free energy
A spontaneous process involves a decrease in Gibbs Free Energy (ΔG < 0).
When does a reaction reach equilibrium?
When the rate of conversion of A to B equals the rate of conversion of B to A
This indicates a balance in reactant concentrations.
What is a coupled reaction?
A situation where a reaction with a positive ΔG occurs linked to a reaction that releases free energy
This allows non-spontaneous reactions to proceed.
What characterizes living organisms in terms of thermodynamics?
They are open systems that never reach equilibrium
This is essential for maintaining life and order.
What is the capacity for work (W)?
A dynamic state related to change
It is measured in Joules (J) or calories (cal).
What do enzymes do in biochemical catalysis?
Reduce the free energy of the transition stage
This allows reactions to occur faster and at lower temperatures.
Describe the lock and key mechanism in enzymes.
Enzyme-substrate complex formation
This mechanism illustrates how specific enzymes interact with their substrates.
What happens to energy in every spontaneous reaction?
It increases the randomness of the universe
This is a key principle in thermodynamics.
Fill in the blank: Energy transformations ultimately increase the ______ of the universe.
entropy
This reflects the tendency towards disorder in energy exchanges.
What is meant by a dynamic steady state in living organisms?
Production rate of a product is balanced with its consumption
This indicates that biological systems maintain homeostasis.
