ENZYMES and Activation Energy

What is Energy? Energy is the ability to cause matter to move or change. All life processes are driven by energy Where does all energy come from?

Chemical Reactions Occurs when bonds are broken and reformed to make different substances. EX: ReactantsProducts CO 2 +H 2 0H 2 CO 3

What is Metabolism? Metabolism is the sum of all chemical reactions in your body - Metabolism is basically two components Literally, you are what you eat! 1.Breaking down foods for energy 2.Building new compounds to make you

What is needed to start a reaction? Energy absorbed Activation energy reactant Products Energy released

What is a Catalyst? A catalyst is anything that lowers activation energy There are basically two kinds: 1. Organic 2. Inorganic Organic catalysts are called Enzymes

Why is the activation energy lower? Energy absorbed Energy released reactant Products Activation energy

Energy absorbed Energy released Reactant Products Comparing Reactions Which line would represent a reaction without an enzyme present? With an enzyme present?

How Do Enzymes Work? Enzymes work like a lock and key. Specific enzymes work with specific substrates. enzyme substrate

How Do Enzymes Work? Each substrate fits into the enzyme’s active site. Then the enzyme controls chemical reaction.

Enzymes can be affected by: Temperature: pH: Concentration: Neutral Battery AcidBleachBlood (7.5)

Cells need energy to do a variety of work: Making new molecules. Building membranes and organelles. Moving molecules in and out of the cell. Movement. All Cells Need Energy

Where Does A Cell Get Energy? Food is broken down to a form the cell can use. Extra energy is stored in an ATP molecule, a nucleotide.

What Is ATP? ATP – adenosine triphosphate is a molecule made up of an adenine, ribose, and 3 phosphate groups. Adenine Ribose

How Does ATP Work? Energy is stored in the bond between the second and third phosphate group. When the bond is broken, energy is released and ADP is formed. Adenine Ribose

ATP – Energy Currency Within a cell, formation of ATP from ADP and phosphate occurs over and over, storing energy each time. As the cell uses energy, ATP breaks down repeatedly to release energy and form ADP and phosphate.

ATP stores Energy ATP is the special carrier molecule that stores energy available for cell use. ATP is the energy currency of the cell; the energy source for all cell functions. ATP ADP P P energy

Making Energy Cells make energy in two ways: –Photosynthesis – takes place in the chloroplasts. –Respiration – takes place in the mitochondria.