exam 1

Question 1

what is the three domain system?

Answer 1

archae, eukarya, and bacteria

Question 2

what is biogensis?

Answer 2

developement of life from pre-exsiting forms of life forms

Question 3

who observed the first microorganisms

Answer 3

Anton van Leeuwenhoek

Question 4

mycology study of?

Answer 4

molds,yeasts, and mushrooms

Question 5

who composed a microscope and observed thin slices of cork. Then he coined the term “cells”.

Answer 5

robert hooke

Question 6

why is mycobacterium difficult to stain?

Answer 6

it’s difficult to stain because of the large amounts of waxlike lipids present in the cell wall.

Question 7

why is gram staining in microbiology important?

Answer 7

it’s important because it differntiates bacterial cells with diff types of cell walls

Question 8

You are performing a gram stain on gram negative bacteria and stop after adding mordant. How well the bacteria appear?

Answer 8

purple

Question 9

which microscope is best for viewing details of internal structures within live cells?

Answer 9

phase contrast microscopy

Question 10

what is incorrect about capsules?

Answer 10

involvement in DNA transfer

Question 11

what is incorrect about prokaryotic cells?

Answer 11

prokaryotes lack a ribosome

Question 12

what is expected to find in acid fast cell walls?

Answer 12

mycolic acid and peptidoglycan

Question 13

what is the function of fimbriae?

Answer 13

numerous and hairlike structures that attach to surfaces

Question 14

what is the function of glycocalyx?

Answer 14

protection from phagocytes

Question 15

what is the function of a cell wall?

Answer 15

protects from osmotic pressure

Question 16

what is the function of pili?

Answer 16

transfers genetic material

Question 17

gram positive bacterium characteristics

Answer 17

gram positive bacterium characteristics

Question 18

gram negative characteristics

Answer 18

lipopolysaccharide, phospholipid, lipoprotein, peptidoglycan, plasma membrane, and O-antigens

Question 19

which of the following is correct regarding prokaryotic cells?

Answer 19

dna not associated with histones

Question 20

what is the difference between eukaryotic and prokaryotic flagella?

Answer 20

eukaryotic flagella have a 9 + 2 arrangment of microtubules

Question 21

what are structures NOT found in prokaryotic cells?

Answer 21

cilia

Question 22

which structures allow a cell to survive adverse environmental conditions?

Answer 22

endospores

Question 23

What is quorum sensing?

Answer 23

the ability of bacteria in biofilm to communicate with each other and coordinate their activities

Question 24

a medium containing chemicals to inhibit growth of gram positive bacteria would be called?

Answer 24

selective

Question 25

what technique is used to seperate bacteria and get individual colonies?

Answer 25

streak plate

Question 26

bacteria is reproduced by ?

Answer 26

binary fission

Question 27

culture mediums consisting of agar, peptone, and beef heart extract is?

Answer 27

a complex medium

Question 28

when bacterial cell reproduce by splitting into two daughter cells, the process is called?

Answer 28

binary fission

Question 29

in what phase of the growth curve is the population-doubling time fastest?

Answer 29

log phase

Question 30

blood agar is used to observe hemolysis or clearing around streptococcus pyogenes colonies is an example of?

Answer 30

differential media

Question 31

T/F: the endosymbiotic theory states that eukaryotic organelles evolved from symbiotic prokaryotes living within other prokaryotes?

Answer 31

true

Question 32

Bacteria characteristics

Answer 32

prokaryotes, double bilayer, petidoglycan,, single cell, divide by binary fission, use flagella for motility

Question 33

archaea characteristics

Answer 33

prokaryotes, lack peptidoglycan cell walls, live in extreme environments, don't cause disease in humans( generally)

Question 34

fungi characteristics

Answer 34

eukaryotes, chitin cell walls,yeast: unicellular, molds/mushrooms: multicellular

Question 35

protozoa

Answer 35

motile via pseudopods, cilia or flagella, reproduce sexually/asexually, free living or require parastic host, eukaryotes

Question 36

algae

Answer 36

eukaryotes, cellulose in cell wall, photosynthesis for energy,unicellular/multicellular, reproduce sexually/ asexually

Question 37

viruses

Answer 37

dna/rna core surrounded by protein coat, required for a living host to replicate, inert outside a living host.

Question 38

who is carl woese?

Answer 38

he created the domain classifcations

Question 39

who is louis pasteur?

Answer 39

demonstrated that microorganisms are present in the air

Question 40

who is rudolf virchow?

Answer 40

said that cells arise from preexisting cells(biogenesis)

Question 41

who is paul ehrilch?

Answer 41

magic bullet. could destroy a pathogen without harming the host

Question 42

who is alexander fleming?

Answer 42

discovered first antibiotic

Question 43

brightfield microscope

Answer 43

bright background, low contrast, both stained/unstained

Question 44

darkfield microscope

Answer 44

dark background, increase contrast between sample & field, some internal structures can be viewed

Question 45

phase contrast

Answer 45

high contrast, can view life and cell internal structures, used to view microbial movement & detecting bacterial structures

Question 46

confocal

Answer 46

cells stained with fluoroscent dyes, laser beam used to illuminate the fluroscent, sharp 3d images, used to study biofilms

Question 47

acidic dye

Answer 47

chromophore is negatively charged, stain binds to molecules that are positively charged on surface of bacterium

Question 48

why is gram staining important for prescription of antibiotic treatment?

Answer 48

distinguishes between gram +/- bacteria. many antibiotics specifically target cell wall synthesis, so it's important to know what type of bacteria it is.

Question 49

basic dye

Answer 49

chromophere is positively charged, stain binds to to molecules that are negatively charged on surface of bacterium

Question 50

acid fast staining

Answer 50

only binds to bacteria that have waxy cell walls which can't be decolorized by alcohol.

Question 51

negative staining for capsules

Answer 51

capsules provide an exterior covering for the bacterium. They are stained with india ink or nigrosin. They appear to be halo around the cell which indicates a capsule is present.

Question 52

What are endospores?

Answer 52

Dormant cellular structures that are resistant to harsh external conditions. The primary stain is malachite green. Cells appear red or pink with green dots when stained.

Question 53

Which microscope forms an image from two sets of light rays, one from the light source and the other diffracted from a structure in the specimen?

Answer 53

phase contrast microscope

Question 54

Bacteria that divide in multiple planes and form grapelike clusters are called

Answer 54

staphylococci.

Question 55

Some bacteria stain Gram-positive and others stain Gram-negative because of differences in the structure of their

Answer 55

cell wall

Question 56

what shape is bacillus?

Answer 56

rod shaped

Question 57

what shape is coccus?

Answer 57

spherical shaped

Question 58

what is the shape of vibrio, spirillum, and spirochete?

Answer 58

spiral

Question 59

what is the bacteria whose arrangment is in pairs?

Answer 59

dipolocci or diplobacilli

Question 60

what bacteria is in clusters?

Answer 60

staphylocci

Question 61

what bacteria is in chains?

Answer 61

streptococci and streptobacilli

Question 62

What are the sizes of two subunits used to compose prokaryotic ribosomes?

Answer 62

30s+50s

Question 63

Which of the following contain 70S ribosomes?

Answer 63

Prokaryotes, mitochondria, and chloroplasts

Question 64

Which of the following is NOT a feature of Mannitol Salt Agar?

Answer 64

ability to differentiate between different types of Gram negative bacteria

Question 65

The following steps occur during binary fission. What is the third step?

Answer 65

inward growth of membrane

Question 66

Which of the following best describes the rate of microbial death when treated with antimicrobial chemicals?

Answer 66

Cells in a population die at a constant rate.

Question 67

Commercial sterilization is a limited heat treatment to destroy

Answer 67

Clostridium botulinum endospores.

Question 68

More than half of our antibiotics are produced by species of

Answer 68

Streptomyces.

Question 69

Which one of the following groups of pathogens are the easiest to treat with antimicrobial agents?

Answer 69

Bacteria

Question 70

One disadvantage to using broad-spectrum antibiotics is that they

Answer 70

destroy normal microbiota.