Test 1

Question 1

ribozyme has

Answer 1

genetic and enzymatic activity

Question 2

acidophile grows optimally in what environment?

Answer 2

pH

Question 3

neutrophiles grow optimally in what environment?

Answer 3

pH from 5.5-8.5

Question 4

alkalophiles grow optimally in what environment?

Answer 4

pH >8.5

Question 5

What are the different shapes of bacteria?

Answer 5

cocci= spherical
bacilli= rod
vibrios= curved rod 
spirilla= sprial
pleiomorphic= variable in shape

Question 6

what happens when facultative anaerobe exhaust/deplete the oxygen?

Answer 6

nothing; they can use oxygen when it’s present, but they can also grow when oxygen isn’t present

Question 7

what type of organism grows in 5 degrees Celsius, pH 4, and no light (and no oxygen)

Answer 7

acidophiles

Question 8

how can you slow down the growth of a microbe?

Answer 8

putting it in the fridge

Question 9

What happens to cell without LPS if you fail to add iodine to gram stain?

Answer 9

The cell will appear pink because there was no iodine to make the purple stay in place; so the purple crystal violet was all washed out with ethanol and then everything was stained pink when safranin was added; false gram negative stain

Question 10

Which organism does not have a cell wall?

Answer 10

mycoplasma

Question 11

major characteristics of the three domains:

Answer 11

histone
chromosome
cell wall

Question 12

cell shape is made/maintained by which enzyme?

Answer 12

MreB protein provides an internal structural support framework
FtsZ directs cell wall formation during cell division

Question 13

bacteria have cholesterol: T/F?

Answer 13

False

Question 14

functions of viruses

Answer 14

replicate inside a host cell

have biochemical activity inside a host cell

Question 15

what is the equation for predicting cell numbers that grow after a certain period of time?

Answer 15

Nt= No x 2^n
No: original population number
n= number of generations in over the time period
Nt= the number in the population at time t

Question 16

if 2 bacteria cell divide every 30 minutes, how may will there be after 10 hours?

Answer 16

2 x 2^20

Question 17

What are bacterial microcompartments that contain enzymes involved in carbon fixation?

Answer 17

carboxysomes

Question 18

What is a polyhydroxyalkanoate (PHA), a polymer belonging to the polyesters class that is bio-derived and is a biodegradable plastic

Answer 18

polyhydroxybutyrate (PHB)

Question 19

What converts hydrogen peroxide into water and oxygen?

Answer 19

catalase enzyme

Question 20

a facultative anaerobic and heterotrophic bacterium has depleted its environment of oxygen; what will happen?

Answer 20

the organism will continue to produce ATP via fermentation

Question 21

beta lactam antibiotics do what?

Answer 21

prevents transpeptidation

found in penicillin, ampicillin, and cephalosporin

Question 22

thick outer layer of peptidoglycan

Answer 22

• usually gram positive bacteria have a very thick layer of peptidoglycan compared to gram negative; this thick layer contains teichoic acids
• gram neg bacteria have a cell wall made of LPS phospholipid unilayer

Question 23

lysozyme causes ___ to form in gram positive cells, which causes lysis
lysozyme causes ___ to form in gram negative cells, which can resist osmotic pressure to an extent

Answer 23

protoplast

spheroplast

Question 24

S-layer

Answer 24

mono-layer of protein that has crystallized, creating an armor for the cell to protect against predation and pH change; usually found in archaea

Question 25

what domain do methanogens fall under?

Answer 25

archaea; found in human gut

Question 26

What does UV radiation do if applied on microbes?

Answer 26

damages DNA

Question 27

A chemical solution is sprayed on a kitchen counter surface. As a result of this treatment, the microbial population on the treated area is reduced by 98%. What is the chemical solution?

Answer 27

disinfecting agent

Question 28

substrate level of ATP synthesis

Answer 28

obligate aerobes produce ATP via substrate level phosphorylation as they metabolize pyruvate to CO2

Question 29

Chemical XB4326 is an antibiotic that inhibits the biosynthesis of bactoprenol (flipase) which is found in bacterial cell membranes. you have prepared some bacteriological agar containing this antibiotic and have streaked a strain of Gram + bacteria on this media. Assume that the microbes have all essential nutrients and incubation conditions that are appropriate for their growth, so you’re only evaluating the effect of the antibiotic. What growth results do you expect on media?

Answer 29

in situ, there will be no growth on the medium, thus no gram stain will be able to be perfomed

Question 30

organism uses CO2 as carbon source; auxotroph for sulfur; in experiments where both CO2 and elemental sulfur are available for the organism, the absence of light makes no impact on its ability to grow; what kind of organism is it not?

Answer 30

phototroph

Question 31

aren’t harmed by the presence of O2 as they don’t use it

Answer 31

aerotolerant

Question 32

can use O2 but can also grow w.o it

Answer 32

facultative anaerobes

Question 33

movement of an organism in response to a chemical stimulus

Answer 33

chemotaxis

Question 34

single-layer phospholipid, early form of plasma membrane that separated environmental chemistry from inner ribozymes

Answer 34

micelle

Question 35

membrane water channels that play critical roles in controlling the water contents of cells

Answer 35

aquaporin

Question 36

membrane transport protein that simultaneously transports two different molecules, in opposite directions, across the membrane

Answer 36

antiport

Question 37

integral membrane protein that is involved in movement of two or more different molecules or ions across a phospholipid membrane in the same direction

Answer 37

symport

Question 38

found in human; grows at temperature range of 15 to 40 deg C

Answer 38

mesophile

Question 39

why did they group archaea and bacteria together?

Answer 39

organisms were separated into prokaryotes or eukaryotes based on the presence of membrane bound organelle structures; only eukaryotes have this so they put archaea and bacteria together

Question 40

Why did archaea have their own domain and who is responsible for that change?

Answer 40

phylogenetic analysis showed major difference; archaea packs DNA in eukaryotic like manner and they also use histones which bacteria don’t have; their plasma membrane has an ether linkage compared to ester linkage in the other 2 domains; archaea also have NAG and NAT, S-layer, and grow at a much wider range than bacteria; they also have a variety of sizes and shapes; carl woese is responsible for sequencing the DNA of rRNA discovering Archaea is different than bacteria

Question 41

rapid DNA replication happens in what phase?

Answer 41

log

Question 42

binary fission happens in what phase?

Answer 42

log

Question 43

what is complex medium?

Answer 43

unknown composition

Question 44

Bacteria lack

Answer 44

cholesterol