Biology - Energy

Energy

The ability to do work

Metabolism

Sum of all the chemical reactions

Three ways to get energy (greatest to least)

Carbohydrates, lipids, proteins

Autotrophs

Make their own food(sugar)

Photoautotroph

Uses sunlight to make sugars

Chemoautotroph

Uses chemicals to make sugar

Heterotrophs

Eat other organisms for sugars

Energy flow

Sun - photoautotrophs - heterotrophs

Cellular respiration

Heterotrophs eat plants and break down sugars to make cellular energy(ATP)

What does ATP stand for (spell right)

Adenosine Triphosphate

Chemical reactions

A process changes one set of chemicals into another

When is energy released?

When chemical bonds are brokwn

When is energy absorbed?

When bonds are formed

Exothermic

Bonds broken - release energy. Ex: fire

Endothermic

Bonds made - absorbs energy. Ex: Ice cube

Activation energy

Energy needed for a chemical reaction to start

Enzymes

Lower the activation energy, used to speed up chemical reactions

True or false: Enzymes only work with one substrate

True

Biochemical reaction

Chemical reactions that take place inside living things

Catalyst

Substances that speed up the rate of chemical reactions by lowering the activation energy

True or false: Enzymes act as catlaysts

True

The reactants of enzyme-catalyzed reactions

Substrates

Active site

Where the substrates bind to the enzyme

What happens when an enzyme is denaturized

the active site becomes distorted

When do enzymes become denaturized

When they are exposed to less than optimal conditions