Unit 2

Question 1

Starch

Answer 1

Complex polysaccharide compound composed of polymers

Question 2

What are the two forms of starch

Answer 2

linear (amylose)
branched (amylopectin)

Question 3

Starch Hydrolysis procedure

Answer 3

Use starch agar plate, add swipe of bacteria, incubate for 24 hours, observe, add Gram iodine, record results

Question 4

Starch Hydrolysis - positive vs. negative

Answer 4

positive - clearing around growth
negative - no clearing around growth

Question 5

is starch hydrolysis a single chemical reaction

Answer 5

yes

Question 6

Starch hydrolysis
one species that test positive and one that tests negative?

Answer 6

positive: B. cereus
negative: E. coli

Question 7

Starch Hydrolysis
biochemical reaction

Answer 7

Starch + H2O —> (arrow is amylase) = glucose

Question 8

Maltose

Answer 8

2 glucose molecules together

Question 9

where do you digest starch

Answer 9

mouth and small intestine

Question 10

what is casease

Answer 10

specific enzyme that some bacteria use to hydrolize the milk protein casein

Question 11

Casein

Answer 11

molecule that gives milk its white color

Question 12

Casein Hydrolysis
procedure

Answer 12

two skim milk plates and add bacteria in one swipe, incubate, observe and record results, incubate, record results (determine positive or negative)

Question 13

is casein hydrolysis a single chemical reaction

Answer 13

yes

Question 14

Casein hydrolysis
biochemical reaction

Answer 14

Casein + H2O —> (arrow is casease) = amino acid

Question 15

Casein Hydrolysis
positive vs. negative results

Answer 15

Positive: show clearing in the agar and around growth
Negative: no clearing around growth/agar

Question 16

Casein Hydrolysis
species that tests positive and species that test negative

Answer 16

positive: B. cereus
negative: E. coli

Question 17

why does casein need to break down into amino acids

Answer 17

too big to get through cell wall

Question 18

what is gelatinase

Answer 18

enzymes that are capable of degrading gelatin through hydrolysis

Question 19

Gelatin Hydrolysis
procedure

Answer 19

get gelatin tubes and stab with the name of the organism and keep one as control tube, incubate, examine, place in refrigerator, observe, place back in incubator

Question 20

Gelatin hydrolysis
positive vs. negative

Answer 20

positive: gelatin is liquid (control is solid)
negative: gelatin is solid

Question 21

Gelatin Hydrolysis
one species that is positive and one that is negative

Answer 21

positive: B. cereus
negative: E. coli

Question 22

Gelatin Hydrolysis
biochemical reaction

Answer 22

Gelatin + H2O –> (arrow is gelatinase) = amino acids

Question 23

what is the point of the starch, casein, and gelatin hydrolysis labs?

Answer 23

-they are essentially the same
-test for extracellular hydrolytic enzymes
-seeing if theres breakdown outside of the cell with a biological catalyst

Question 24

fructose

Answer 24

C6H12O6

Question 25

Mannitol Salt Agar
what didn’t have growth and what did

Answer 25

no growth: E. Coli
had growth: S. aureus, S. epidermidis

Question 26

Mannitol Salt Agar
why was there no growth and growth

Answer 26

-e.coli didn’t have growth as the salt concentration kills bacteria by dehydrating
-s. aureus and s. epidermidis had growth because of their thick walls and salt concentration (they can survive high concentrations)

Question 27

what has such high osmotic pressure that it will never go bad

Answer 27

honey

Question 28

E. Coli is ____% solute, _____% H20

Answer 28

0.9;99.1 = mostly water

Question 29

Mannitol Salt Agar is ____% solute, ____% H2O

Answer 29

7.5;92.5

Question 30

When there is more solute outside of the cell than inside the cell, it’s called _________

Answer 30

hypertonic

Question 31

What kind of species can generally grow on salt agar plates?

Answer 31

Gram-positive spheres

Question 32

What kind of species generally can’t grow on salt agar plates?

Answer 32

Gram-negative bacilli

Question 33

S. aureus is yellow = able to ______ ________

Answer 33

ferment manitol

Question 34

Mannitol

Answer 34

C6H14O6

Question 35

Fermentation is a ______ ________

Answer 35

metabolic pathway

Question 36

Gained electrons is __________
Lost electrons is ___________
do they have to happen at the same time
why does the cell do that?

Answer 36

Reduction
Oxidation
yes
to make ATP