ENERGY

study slide set

what is energy?

ability to do work

why is energy important for our cells"?

we have thousands of reactions going on all the time and they need energy to accomplish

why is energy important to humans?

we will die without it

what are the 3 energy conditions that will determine if a reaction will occur?

1. decrease in energy level

2. increases in entropy

3. reactant and product concentrations

what are 2 types of biological reactions?

catabolic and anabolic

catabolic =

degradative pathway (breakdown)

anabolic =

synthesis pathway (build up)

catabolic (ATP-ADP or ADP-ATP)

ADP»ATP

anabolic (ATP-ADP or ADP-ATP)

ATP»ADP

in catabolic, is the product molecule of higher or lower energy than the reactant?

lower

in anabolic, is the product molecule of higher or lower energy than the reactant?

higher

what are the 2 main forms of energy?

potential and kinetic

what are the 3 types of potential energy?

gravitational, chemical, elastic. (GCE)

what are the 3 types of kinetic energy?

mechanical, electrical, magnetic (MEM)

what is energy from the sun called?

electromagnetic energy

where does energy from sun get stored?

in the bonds of organic compounds

what are the 3 laws that govern chemical reactions?

1st law of thermodynamics, second law of thermodynamics, law of entropy

which law states that energy is never 100% efficient?

second

which law is a measure of the degree of disorder?

principle of entropy

which law states that the total amount of energy in the universe remains constant?

first

which law states that energy cannot be created or destroyed, but only undergo conversions?

first

which law states that everything spontaneously moves from high order to low order?

second

how do living things resist the flow toward maximum entropy?

because of energy from sun

what type of molecule are enzymes?

protein molecule

what is activation energy?

amount of energy necessary for a reaction to occur

what is a catalyst?

substance that speeds up chemical reactions

what are the 3 factors that influence enzymes activity?

temp, pH, salt concentration

does high or low temp denature enzymes?

high

does high or low pH denature enzymes?

low

does high or low salt concentration denature an enzyme?

high

what is denaturing?

disrupting the 3D shape of an enzyme so that it no longer functions

what is the site on an enzyme where a reaction will take place?

active site

what is a molecule that will react called?

substrate

what is a model that represents enzyme activity called?

lock and key model

what are the 2 main categories of transport across a membrane?

active and passive

which transport needs an energy input to proceed?

active

which transport moves molecules from high to low concentration?

passive

which transport moves molecules across that are too big to pass through membrane spaces?

active

what involves bulk transport?

endocytosis and exocytosis

what forms around molecules that are moving in bulk either out of or into the cell?

vesicles

what 4 factors affect the diffusion rate across a membrane?

1. concentration gradient

2. molecular size

3. temp

4. electrical or pressure gradients

how does a temp affect diffusion rate?

higher temp, faster diffusion

how does molecular size affect diffusion rate?

smaller molecules, faster diffusion

how does concentration gradient affect diffusion rate?

steeper gradient, faster diffusion

what is a gradient?

how much more of something there is on one side of membrane than other

how do electrical or pressure gradients affect diffusion rate?

steeper gradient, faster diffusion