post lab discussion: exp. 3

Question 1

mostly proteins molecules, they act as catalyst for biochemical reaction

Answer 1

enzymes

catalyst _ speed up chemical reaction, without changing free energy

Question 2

enzymes are very specific, what type of reaction does each enzymes catalyzes reaction or type of reaction only

Answer 2

oxidoreductase
ligase
lyase
transferase
hydrolase
isomerase

Question 3

a reactant, where substances upon which the enzymes acts

Answer 3

substrate

Question 4

how enzyme works

Answer 4

enzyme contains active site that binds the substrate = ES complex
then release products once reaction has occurred

Question 5

measure of rate at which enzyme converts substrate to products in a biochemical reaction

Answer 5

enzyme activity

Question 6

factors that affect the enzyme activity

Answer 6

temp
pH
substrate conc.
enzyme conc.

Question 7

this reacts with starch

Answer 7

iodine which forms a starch/ iodine complex = blue color to the reaction mixture

Question 8

salivary amylase

Answer 8

is an enzyme in your saliva that helps start breaking down starch in your food into smaller sugars when you chew.

Question 9

from test tube 1 - 5 which is your
positive control:
negative control:

Answer 9

positive control: test tube 1
negative control: test tube 5

• add drops of saliva sample in test tube 2-4

Question 10

briefly explain the effect and pH and inhibitor

Answer 10

a amylases

optimum pH of 7:
enzyme is effective
yellow color soln

inhibitor, silver nitrate:
block reduce the activity
blue color soln as no starch is broken down
other inhibitors - 1% NaCl and (%& ethanol

Question 11

denaturation

Answer 11

unraveling of the 3D structure of a macromolecule caused by the breakdown of noncovalent interactions

heat
large changes in pH, alter charges on side chains
detergents
urea and guanidine hydrochloride (disrupt hydrogen bonding)
B-mercaptoethanol

Question 12

true or false:
if there is no biological activity, the enzyme activity will decrease

Answer 12

true