CH 19 notes

Question 1

Luciferinase

Answer 1

Enzyme found in fireflies tails–light production

Question 2

Catalyst

Answer 2

anything that speeds up rate of RXN but itself is unchanged

Question 3

How does catalyst work?

Answer 3

Lowers the energy of the transition state and therefore the activation energy (Ea) of RXN

Question 4

Enzyme

Answer 4

PRO or other molecule that acts as a catalyst for a biochemical RXN

WATER SOLUBLE
GLOBULAR PRO

Question 5

Active Site

Answer 5

pocket in an enzyme w. specific shape and chemical makeup necessary to bind a substrate

Question 6

Substrate

Answer 6

reactant in an enzyme-catalyzed RXN

Question 7

Specificity enzyme

Answer 7

limitation of the activity of an enzyme to a specific substrate, specific RXN, or specific type of RXN

Catalase almost completely specific for decomposition of hydrogen peroxide

Question 8

Catalysis of enzymes

Answer 8

enzymes can also be specific to STEREOCHEMISTRY

catalytic activity of enzyme is measured by its turnover number

Question 9

Turnover #

Answer 9

max # of substrate molecules acted upon by one molecule of enzyme per unit time

Question 10

Cofactor

Answer 10

nonPRO pt of an enzyme that is essential to the enzyme’s catalytic activity, a metal ion of coenzyme

EX:
Fe     Mn
Zn     Mo
Cu    Co
Ni     V
   Se

Question 11

Coenzyme

Answer 11

organic molecule that acts as an enzyme cofactor

certain vitamins are critical building blocks for coenzymes
they’re dietary necessities bc CANT BE SYNTHESIZED IN BODY

Question 12

Oxidoreductases

Answer 12

catalyze redox runs of substrate molecules
usually addition or removal of O2 or H+
must have coenzyme thats either OXIDIZED OR REDUCED

Question 13

Transferases

Answer 13

catalyze transfer of a functional grip form on molecule to another

Question 14

Hydrolases

Answer 14

catalyze the hydrolysis of substrates

EX:
digestion of CHO and PRO

Question 15

Isomerases

Answer 15

catalyze the isomerization (rearrangement of atoms) of a substrate in RXNs that have but one substrate and one product

Question 16

Lyases

Answer 16

Catalyze the addition of a molecule ( H20, CO2, NH3) to a double bond OR reverse RXN in which molecule is eliminated to form a double bond

Question 17

LIGASES

Answer 17

catalyze the bonding together or TWO substrate molecules

Question 18

Lock and Key

Answer 18

historical model

rigid space for rigid piece

Question 19

Induced- fit model

Answer 19

enzyme action

has flexible active site changes shape to accommodate substrate

Question 20

Induced- fit model

Proximity effect

Answer 20

joining up of the enzyme with substrate

Question 21

Induced- fit model

Orientation effx

Answer 21

holding of substrates at the exact distance and in the exact orientation necessary for a RXn

Question 22

Induced- fit model

Catalytic effx

Answer 22

provide ACIDIc, BASIC or other groups required for catalysis

Question 23

Induced- fit model

Energy Effect

Answer 23

Lowering energy barrier by induing strain in bonds in the substrate molecule

Question 24

Substrate concentration

Answer 24

as substrate concentration increases– rate of RXN INCREASES

starts to level off when the substrates concentration gets high enough that most enzymes are taken

levels off –>add more substrate

Question 25

Enzyme concentration

Answer 25

if there is plenty of substrate...RXN rate INCREASES linearly w/ enzyme concentration

Question 26

Temperature on enzyme activity

Answer 26

INCREASE in temp INCREASES rate of RXN until temp. gets HIGH enough to DENATURE enzyme..then SHARP DECREASE in activity

Question 27

effect of pH on enzyme activity

Answer 27

each enzyme will have an optimal pH that coincides w. the natural environment of the catalyzed RXn

Question 28

Enzyme activation

Answer 28

any process that INITIATES or increase action of enzyme

Question 29

Enzyme inhibition

Answer 29

any process that SLOWS/ STOPS action of enzyme

Question 30

Feedback Control

Answer 30

regulation of an enzyme's activity by the product of a RXN later in pathway A----(enzym. 1)--> B---(enzym. 2)---> C ---ETC--->

Question 31

Allosteric Control

Answer 31

interaction in which the binding of a regulator at one site on PRO aft the PRO's ability to bind another molecule at different site EITHER POSI+IVE (enzyme becomes a better catalyst) OR NEGATiVe----- (enzyme becomes a less effective catalyst)

Question 32

Allosteric Enzyme

Answer 32

enzyme whose activity is controlled by the binging of an activator or inhibitor at location other than active site

Question 33

Uncompetitive Inhibition

Answer 33

enzyme regulation in which inhibitor binds reversibly to the enzyme substrate complex blocks the binding of the second substrate to active site

Question 34

Reversible Competitive Inhibition

Answer 34

enzyme regulation in which an inhibitor competes w/ a substrate for binding to enzyme active site

Question 35

Irreversible Inhibition

Answer 35

enzyme deactivation in which an inhibitor forms covalent bonds for the active site PERMANTELY BLOCKS ACTIVE SITE!!!!!

Question 36

Covalent Modification

Answer 36

removal of addition of an covalently bonded group to modify the activity of enzyme

Question 37

Zygomen

Answer 37

compound that becomes and active enzyme after undergoing a chemical change

Question 38

Genetic (enzyme) control

Answer 38

regulation of enzyme activity by control of the synthesis of enzymes

Question 39

VITAMINS

Answer 39

organic molecule essential in trace amounts MUST BE OBTAINED FROM DIET!!!! cannot be synthesized in body

Question 40

Water- Soluble Vitamins

Answer 40

Must be replaced daily due to solubility in water (urine) MOST ARE COENZYMES ALL B VITS and C-ANTIOXIDANT

Question 41

Vitamin A

Answer 41

ANTIOXIDANT | EYE FUNCTION and SKIN

Question 42

Vitamin D

Answer 42

related to CHOLESTEROL | NEEDED FOR BONE MASS

Question 43

Vitamin E

Answer 43

ANTIOXIDANT PREVENTS form of ANEMIA protects vit A

Question 44

Vitamin K

Answer 44

ESSENTIAL FOR LIVER | prevents BLEEDING DISORDERS (helps blood clot)

Question 45

ANITOXIDANT

Answer 45

substance that prevents oxidation by reacting with an oxidizing agent

Question 46

``` What do VIT C VIT E BETA-CAROTENE MINERAL SELENIUM have in common and what do they do? ```

Answer 46

DIETARY ANTIOXIDANTS work together to defuse the potentially harmful action of free radicals

Question 47

Free Radical

Answer 47

Atom or molecule wit h an unpaired electron wants to attach to anything bad for body