Biology Unit 3

Front 1

First law of thermodynamics

Back 1

total energy in the universe is constant (energy is neither created nor destroyed)

Front 2

second law

Back 2

total usuable energy in a system decreases as energy conversions take place (given off as heat). This increases entropy (randomness, disorder)

Front 3

free energy

Back 3

amount of energy available to break and reform bonds

Front 4

Delta G

Back 4

-=exergonic reaction, energy releasing

Front 5

coupled reaction

Back 5

endergonic reactions can occur when coupled to series or pathways of reactions that are exergonic ("domino effect")

Front 6

active sites on enzymes

Back 6

a place or area on a protein that is determined by its tertiary structure

Front 7

substrates

Back 7

bind to specific active site of a specific protein. (after a substrate binds it shifts tertiary strucutre which may enhance of inhibit further bonding. known as induced fit

Front 8

How do enzymes lower activation energy?

Back 8

-increase local concentration of molecules
-position molecules in relation to each other so they can bond

Front 9

competitive inhibition

Back 9

a molecule other than the usual substrate binds in the active site and blocks normal product formation

Front 10

allosteric effects

Back 10

molecules bind on enzyme somewhere other than the active site but still affect aite by altering tertiary structure
-non-competitive inhibition

Front 11

cofactors

Back 11

molecules that assit in enzyme function

Front 12

metal ions

Back 12

can pull electrons away from substrate molecules because of their charge

Front 13

coenzymes

Back 13

cofactors that are non-protein organic molecules. often operate to transfer electrons between molecules, therefore are redox pairs

Front 14

multienzyme complexes

Back 14

increase efficiency of catalytic events by increasing concentration of reactants, decreasing competeing reactions, operating as a unit

Front 15

ATP structure

Back 15

-one nitrogen base-adenine
-one sugar-ribose
-one-three phosphate group

Front 16

ATP hydrolysis

Back 16

-liberates 7 Kcal/bond
-drives endergonic reactions
-phosphorylates-add a phosphate functional group
-can cause couple reactions

Front 17

glycolysis

Back 17

sugar splitting, occurs in the cytoplasm of all cells
-energy obtained from breaking the C-H bonds of glucose

Front 18

Glycolysis reaction

Back 18

6 carbons (glucose) yields 2 molecules of pyruvic acid (3 carbons)
-net yield= 2 ATP, 2 NADH

Front 19

Kreb's cycle

Back 19

-occurs in the matrix of the mitochondria
-1 ATP per turn

Front 20

electron transport chain

Back 20

electrons are passed from glucose to oxygen in a series of steps with electrons "falling", releasing stored energy at each step.
-occurs in the inner inner mitochondrial membrane, the cristae

Front 21

cellular respiration of fats

Back 21

in the matrix lipids either become
1. glycerol or fatty acid
2. broken down into fatty acids (chains)->2 carbon pieces (acetyl groups) -> acetyl CoA

Front 22

Fermentation

Back 22

-anaerobic respiration
-conversion of pyruvic acid to either ethanol or lactic acid
-small amount of ATP made

Front 23

chloroplasts

Back 23

the only pigment that directly converts light energy to chemical energy by boosting electrons to higher energy levels

Front 24

CAM

Back 24

stomates stay closed during the day, but open at night