energy transformation and ATP

What is metabolism?

The sum of all chemical reactions occurring in a biological system at a given time.

What is anabolism?

Chemical reactions that link less complex molecules to more complex molecules.

Give an example of an anabolic reaction.

Making glycogen from glucose or building membrane transport proteins.

What is catabolism?

Chemical reactions that break more complex molecules into less complex molecules.

Give an example of a catabolic reaction.

Hydrolysis of proteins to amino acids or starch to glucose.

What is potential energy?

Stored energy of state or position, such as in chemical bonds.

What is kinetic energy?

The energy that causes change or work, including molecular motion or heat.

What does the first law of thermodynamics state?

Energy is neither created nor destroyed.

What does the second law of thermodynamics state?

Disorder in a system tends to increase.

What is the Gibbs free energy equation?

ΔG = ΔH - TΔS

What does a negative ΔG indicate?

Free energy is released (exergonic).

What does a positive ΔG indicate?

Free energy is required (endergonic).

What is the ultimate source of energy for most life on Earth?

The Sun.

What is an exergonic reaction?

A reaction that releases free energy (ΔG < 0).

What is an endergonic reaction?

A reaction that consumes free energy (ΔG > 0).

What is ATP?

Adenosine triphosphate, the energy currency of a cell.

How does ATP drive cellular processes?

By coupling exergonic and endergonic reactions through energy transfer.

chemical bond

energy stored in covalent bonds is released during the hydrolysis of polymers

electrical

help drive the movement of ions through channels

heat

can be released during chemical reactions, can alter the internal temp of organisms

light

captured by pigments in the eye and by plant pigments during photosynthesis

mechanical

used during muscle movements and movements within the cell