UNIT 4 BIOLOGY TEST

energy

the ability to do work

kinetic energy

energy of motion used for cellular work

potential energy

stored energy in the bonds of molecules

First Law of Thermodynamics

Energy is not created nor destroyed, but it can change form

Second Law of Thermodynamics

With every conversion of energy, there is an increase in entropy (less usable energy available)

Car and Cell Analogy of First Law

chemical energy in gasoline is converted into mechanical energy that moves the wheels and chemical energy in glucose is converted into energy used for cellular work

Car and Cell Analogy of Second Law

only 25% of the energy stored in the bonds of gasoline are converted into the kinetic energy of the car’s movement and much of the energy stored in the bonds of glucose is released as waste (heat+ carbon dioxide)

Exergonic Reactions

reactions where reactants have more total energy than the products resulting in broken bonds and a net release of energy (less reactants than products)

Endergonic Reactions

products of a reaction have more total energy than the reactant resulting in an input of energy and the form of bonds (more reactants than products)

Exergonic Reaction Graph

Endergonic Reaction Graph

competitive inhibition

when a substrate molecule is prevented from binding to the active site of an enzyme

Non-competitive (allosteric) Inhibition

something else that changes the enzyme so the active site doesn’t work

Purpose of non-competitive inhibition

To prevent an overabundance of molecules in the cell to maintain homeostasis

Feedback Loops

pathway for building or breaking molecules that can involve many steps, which may require several enzymes

How do enzymes denature

Change in temperature, pH, and ion concentration

Reactions will happen faster with

More substrates, more enzymes, and higher temperatures

co-enzyme

organic molecule which helps the enzyme react

examples of co-enzymes

Vitamins

cofactor

irons which helps the enzyme react

examples of cofactors

Magnesium, Iron, Zinc

metabolism

all of the chemical processes that occur within a living organism in order to maintain life

catabolic reaction

chemical reaction that results in the breakdown of large molecules into smaller-sized molecules (exergonic)

anabolic reaction

chemical reaction that absorb energy and build bigger molecules from smaller ones (endergonic)

denaturation

loss of shape and function

aerobic respiration steps

glycolysis, Krebs cycle, electron transport chain

glycolysis

the process in which glucose is broken down to produce energy, and two molecules of pyruvate, ATP, NADH and water