Metabolism: Lesson 1 (Thermochemistry)

Question 1

Metabolism:

Answer 1

• The overall process by which an organism obtains nutrients, extracts energy from them and uses that energy.
• The sum of all chemical reactions happening in a cell/ organism.

Question 2

Includes both:

Answer 2

Anabolic Process - building complex molecules from simpler ones.
• Synthesizing Polymers

Catabolic Process - breaking down complex molecules into simpler ones.
• Hydrolysis of Polymers

Question 3

Energy:

Answer 3

• Energy - the capacity to do work.
• Work - when energy is used to move an object against an opposing force.

• Types of Energy: 
—> Kinetic (Motion)
—> Electric
—> Nuclear
—> Sound
—> Thermal (Heat)
—> Gravitational 
—> Chemical

Question 4

Potential Energy

Answer 4

Potential Energy - Stored energy that matter possess because of its location or chemical structure.

• Ex. Gravitational Potential Energy - diver at top of diving board.
• Ex. Chemical Potential Energy - Stored in molecules because of the arrangement of their atoms.

Question 5

Thermodynamics

Answer 5

Thermodynamics - the study of energy transformations.

Question 6

What’s the First Law of Thermodynamics?

Answer 6

First Law of Thermodynamics: energy cannot he created nor destroyed, it can only be converted from one form to another. The total amount of energy in the universe is constant.

Question 7

Bond Energy:

Answer 7

Conversion of Energy from one form to another depends on breaking chemical bonds and forming new ones. This transfers energy from bond to bond.

• When bonds break, energy must be absorbed.
• When new bonds form, energy is released.

The greater the bond energy:
• The more chemically stable the bond.
• The more energy required to break the bond.

All chemical reactions require an initial input of energy to break the bonds of the reactants and start the reaction - called Activation Energy.

Question 8

Role of Exothermic/ Exergonic Reactions:

Answer 8

• Releases energy.

* Energy used to break reactant bonds < Energy released when product bonds form.

Question 9

Role of Endothermic/ Endergonic Reactions:

Answer 9

• Energy is absorbed.

* Energy used to break reactant bonds > Energy released when product bonds form.