exam 2

Question 1

viruses

Answer 1

not considered cells, not considered to be alive

Question 2

characteristics of viruses

Answer 2

obligate intracellular parasites, non living, only purpose is to make more viruses

Question 3

what is the purpose of viruses?

Answer 3

to make more viruses

Question 4

why are viruses not considered living?

Answer 4

not cellular, can only replicate inside of a host cell, no ATP generating system, no ribosomes, only contain ONE nucleic acid, no metabolism

Question 5

what are viruses made of?

Answer 5

protein coat, nucleic acid

Question 6

protein coat

Answer 6

made of capsomeres, protects the nucleic acid, responsible for shape

Question 7

nucleic acid

Answer 7

“heart” of the virus, either DNA or RNA, not both

Question 8

do all viruses have an envelope?

Answer 8

only some, but they all have a nucleic acid and protein coat

Question 9

enveloped viruses

Answer 9

usually have spike proteins, extra “coat” around the capsid

Question 10

virus specificity (3 types)

Answer 10

animal viruses, plant viruses, bacterial viruses

Question 11

how can we classify viruses?

Answer 11

size, shape, enveloped or not, type of nucleic acid, specificity

Question 12

what is the purpose of viruses

Answer 12

the one purpose is to replicate

Question 13

how do viruses enter in to host cells?

Answer 13

the viral envelope or capsid fuses with the plasma membrane

Question 14

viral budding

Answer 14

NOT THE SAME as yeast budding, the viral capsid “pinches” off with the plasma membrane of the host cell

Question 15

lysogenic conversion

Answer 15

imparting a new characteristic to lysogenic cell from the prophage in the host cell

Question 16

what is an oncogenic virus?

Answer 16

a cancer causing virus; the virus will enter into the body and change genetic material

Question 17

what are ways to control viral infections

Answer 17

vaccination, anti viral medication (not antibiotics)

Question 18

viroid

Answer 18

“naked” RNA, no protein coat, this is NOT a virus
example: potato spindle tuber disease

Question 19

prions

Answer 19

infectious protein, not a virus and not a viroid

Question 20

prion diseases (5)

Answer 20

scrapie, kuru, chronic wasting disease, mad cow disease, creutzfeldt Jakob disease

Question 21

what is mad cow disease scientific name?

Answer 21

bovine spongiform encephalopathy

Question 22

apply enzymatic activity to the reaction of lactose to glucose and galactose

Answer 22

if we were to put lactose in water, it would take over a year to break down, with an enzyme, reaction time is sped up

Question 23

ribozymes

Answer 23

catalytic RNA

Question 24

can enzymes catalyze all reactions

Answer 24

no, they can catalyze spontaneous reactions ONLY

Question 25

are all enzymes proteins

Answer 25

yes, but not all proteins are enzymes

Question 26

what is the purpose of a cofactor

Answer 26

to "help" the enzyme bind to the substrate

Question 27

what is the difference between a cofactor and a coenzyme?

Answer 27

a cofactor is inorganic, a coenzyme is organic (hydrocarbon)

Question 28

is a coenzyme a protein?

Answer 28

no

Question 29

what 3 factors affect enzymatic activity?

Answer 29

temperature, pH, substrate concentration

Question 30

how does enzyme concentration affect activity?

Answer 30

it doesn't, only substrate concentration does

Question 31

denaturation of a protein

Answer 31

enzyme will unfold and not come back together if conditions are too extreme (ex: pH or temp)

Question 32

what is the energy currency of the cell?

Answer 32

ATP

Question 33

why doesn't the body use PEP/pyruvate?

Answer 33

it has twice the energy but it costs too much energy to make it, energy currency must be intermediate

Question 34

what nutrients are required by the cell?

Answer 34

carbon source, nitrogen source, certain inorganic ions, essential metabolites, water

Question 35

carbon sources

Answer 35

carbohydrates, amino acids, CO2

Question 36

nitrogen sources

Answer 36

amino acids, NH4, N2

Question 37

inorganic ion sources

Answer 37

Mg2+, PO43-

Question 38

why isn't oxygen considered a nutrient?

Answer 38

it is not broken down for energy, it only serves at the final electron acceptor

Question 39

nitrogen fixation

Answer 39

some microorganisms can convert atmospheric molecular nitrogen into organic nitrogen

Question 40

is protein a nutrient for a cell?

Answer 40

NO, but amino acids are, proteins are too large to get in to the cells

Question 41

how do we measure growth of microorganisms?

Answer 41

measure increase in numbers

Question 42

is binary fission the same thing as mitosis?

Answer 42

no (no nucleus)

Question 43

what are the three conditions for growth of a microorganism

Answer 43

temperature, pH, oxygen

Question 44

how are optimal conditions for growth and enzyme activity related

Answer 44

an organism will grow well if its enzymes are functioning well

Question 45

aerobic

Answer 45

requires oxygen

Question 46

anaerobic

Answer 46

requires lack of oxygen

Question 47

what do all organisms produce in the presence of oxygen?

Answer 47

superoxide, it is deadly, organisms that can survive produce superoxide dismutase

Question 48

direct microscope count

Answer 48

measures growth by counting individual cells

Question 49

dilution and plating

Answer 49

counts by multiplying by dilution factor

Question 50

what is metabolism?

Answer 50

sum of all chemical reactions in a cell

Question 51

catabolism

Answer 51

break down

Question 52

anabolism

Answer 52

build up

Question 53

what is biological oxidation?

Answer 53

when electrons and HYDROGEN atoms are removed

Question 54

what is substrate level phosphorylation (reaction)

Answer 54

C-C-C-P + ADP --> C-C-C + ATP

Question 55

what kind of respiration does streptococcus perform?

Answer 55

it is missing an enzyme, so it can only ferment (anaerobic)

Question 56

in what events is ATP produced by substrate level phosphorylation?

Answer 56

in glycolysis and Krebs cycle

Question 57

what are the 2 products of glycolysis?

Answer 57

pyruvate (pyruvic acid) and NADH

Question 58

chaim weizmann

Answer 58

discovered process by which microbes produced acetone and butanol (fermentation)

Question 59

what kind of reaction is the ETC

Answer 59

oxidation reduction

Question 60

how does chemiosmosis lead to ATP synthesis?

Answer 60

as electrons lose their energy, they force protons to the outside, they get back in through ATP synthase, the force is the energy that joins ADP to Pi

Question 61

how does cyanide kill us

Answer 61

it binds and interferes with electron transport

Question 62

what are the core pathways?

Answer 62

Glycolysis and the Kreb's cycle

Question 63

what do the core pathways provide

Answer 63

the building blocks for anabolism of nucleic acids, proteins and other nutrients

Question 64

the core pathways are critical for...

Answer 64

catabolism and anabolism