Exam 3 Review

Question 1

First Law of Thermodynamics

Answer 1

energy cannot be created or destroyed (only converted to other forms)

Question 2

Second Law of Thermodynamics

Answer 2

energy transfers/transformations are never completely efficient; some amount of energy is lost, typically heat energy

Question 3

Hydrolysis reactions
what is it
example

Answer 3

-adding water to break apart molecules
-ex. starch hydrolysis - starch is hydrolyzed by amylase and converted to sugar, identifies bacteria that can hydrolyze starch

Question 4

Condensation (dehydration synthesis)

Answer 4

two molecules from larger molecule with a loss of smaller water which is water

Question 5

Protein

Answer 5

long chain of amino acids joined together by peptide bonds

Question 6

Amino acids

Answer 6

smaller molecules that combine to form protein

Question 7

Lipids

Answer 7

compounds including fats, oils, etc. that are not soluble in water

Question 8

Monosacccharides

Answer 8

sugars that cannot be broken down further (ex. glucose, fructose)

Question 9

Disaccharides

Answer 9

sugars formed when two monosaccharides are joined together by glycosidic linkage
ex. sucrose, lactose

Question 10

Polysaccharides

Answer 10

large chain of molecules composed of tens of thousands of monosaccharides linked together by glycosidic linkage

Question 11

Carbohydrates

Answer 11

comprised of carbon, hydrogen, and oxygen atoms
-will break down into glucose

Question 12

Nucleic Acids

Answer 12

composed of nucleotide chain
-carry genetic information

Question 13

What are enzymes and how do they work

Answer 13

Biological catalyst, reduces activation energy

Question 14

What is a cofactor?

Answer 14

A non-protein molecule that supports the function of a protein

Question 15

Sterilization

Answer 15

complete removal or killing of vegetative cells, endospores, viruses, etc.

Question 16

Disinfection

Answer 16

inactivates most microbes on the surface, but some still remain (not considered sterile)

Question 17

Antisepsis

Answer 17

antimicrobial chemicals like hydrogen peroxide remove pathogens but not all
-chemicals safe for skin

Question 18

Chemotherapy

Answer 18

treatment that uses drugs/antibiotics to stop the growth (killing them or stopping from dividing); ex. cancer, using antibiotics for treatment

Question 19

What is aseptic technique and what does it mean?

Answer 19

Method used to sterilize and main sterilization of the species/object. Important that there are no pathogens present

Question 20

Factors that influence microbial activity

Answer 20

temperature, pH, osmotic pressure

Question 21

Discuss the statement “There is no such thing as almost sterile.”

Answer 21

It’s either sterile or not sterile, there is no in between. One pathogen leads to spreading, so it’s either sterile or not.

Question 22

Describe correct procedure for Streak Plate

Answer 22

-to isolate cultures
Flame loop, collect bacteria on loop, inoculate plate (start in one quadrant, rotate, and continue flaming loop between quadrant streaks)

Question 23

Compare dry heat with moist heat for sterilization

Answer 23

-Dry: used in labs, destroys microorganisms, applied for long periods of time
-Moist: more effective as it penetrates cells better, use autoclave to sterilize objects, uses steam and pressure to destroy all microorganisms

Question 24

Bacterial Population Count

Answer 24

Obtain dilution tubes and aseptically transfer as described to get a diluted portion of the sample that has a low number of bacteria so that we are able to count individual colonies. Diluted samples are then added to different plates, incubated, and then counted.

Question 25

What does temp, pH, and osmotic pressure affect?

Answer 25

amino acid sequence

Question 26

how does the temp control the process?

Answer 26

high temps cause bonds to break, protein no longer has right shape and is affected

Question 27

how does pH affect the process?

Answer 27

pH affects protein, optimal pH - 6-8
human blood pH = 7.35-7.45 av. 7.4
acidosis- fall below levels
alkalosis - go above levels

Question 28

structure of primary
four levels

Answer 28

primary: amino acids
secondary: alpha beated helix and/or b pleated sheet
tertiary: globular shape held together by disulfide bonds
quaternary: 2 or more amino acid sequence

Question 29

purpose of stomach

Answer 29

breakdown proteins, that’s why it’s more acidic

Question 30

how does osmotic pressure impact?

Answer 30

interferes with hydrogen bonding, interrupts secondary shapes

Question 31

how does alcohol impact?

Answer 31

denatures proteins

Question 32

how does heavy metals impact?

Answer 32

bind to active site aka competitive inhibitor
makes others not work

Question 33

ending in -cillins

Answer 33

antibiotics
attacking proteins, won’t let them build cell wall

Question 34

broad spectrum

Answer 34

stop proteins from being built

Question 35

how does UV light affect process?

Answer 35

affects DNA, causes thymines to covalently bond together
-thymine dimer makes it so they don’t have the right sequence and they die