(12) Bioenergetics

The currency of energy in a cell is in the form of _

heat

1st law of thermodynamics

energy cannot be created or destroyed

2nd law of thermodynamics

we are moving towards maximum entropy in the universe

Though it may look like a cell defies the 2nd law of thermodynamics, why don't they?

they releases heat energy into the environment, thus increasing the entropy of the environment

What primary source of energy sustains all cells on earth?

electromagnetic radiation from the sun

In the oxidation of an organic compound, what happens?

carbon loses electrons which releases energy

Oxidation indicates a (loss or gain) of _

loss of electrons

Reduction indicates a (loss or gain) of _

gain of electrons

Higher order organic macromolecules are possible to make through the process of _

reduction

Most stable form of carbon

CO2

Glucose is (stable or unstable?) meaning it is highly (reduced or oxidized?)

unstable; reduced

Catabolism

the creation of energy by breaking down molecules (usually organic molecules are oxidized)

Reduction makes (high/low) energy compounds from (high/low energy) compounds

high;low

Oxidation makes (high/low) energy compounds from (high/low energy) compounds

low;High

Anabolism

the synthesis of higher energy compounds from lower energy compounds in cells (reduction is involved in this pathway). Consumes energy.

Anabolic and catabolic pathways are and

stepwise and controlled

In certain catabolic steps, energy may be harvested by converting to

ADP to ATP

In certain catabolic pathways, electrons may be conserved by converting ____ to ____

NAD+ to NADH

How does NAD+ get converted to NADH

it accepts a hydride (H- which is a hydrogen atom with two electrons)

Hydrogen atom vs a proton vs hydride

hydrogen atom is a proton with one electron. A proton (H+) has no electron associated with it. Hydride (H-) is a porton associated with two electrons

In anabolic process, energy may be consumed by converting _ to ____

ATP to ADP

In anabolic process, electrons may be used by converting ____ to ____

NADH to NAD+

Cells must maintain energy charge. What does that mean?

cells must consistently maintain a ratio of ATP to ADP to AMP where they keep a pool of ATP that is larger than ADP and a ADP pool larger than AMP.

Diseased cells are unable to their energy consumption/ production systems

control/regulate