chapter4 (diana's version) microscopy

Question 1

what does the term compound mean ?

Answer 1

the term compound mean, there is two things happening at once

Question 2

what uses a light bulb to energize the specimen

Answer 2

compound light microscope

Question 3

name the three kinds of electron microscopes

Answer 3

scanning electron microscopy
scanning transmission microscopy
and scanning tunneling microscopy

Question 4

what is the first to magnifying what ever is on the slide?

Answer 4

objective lens

Question 5

name the microscope that contains a short wavelength and a long wavelength?

Answer 5

light microscope are typically the one with longer wavelength, and electron microscope are the ones with shorter wavelength

Question 6

does a microwave have a long or short wavelength?

Answer 6

it has a long wavelength

Question 7

light microscope is fine for not fine detailed such as bacteria?

Answer 7

false, if we are elaborating on bacteria we need to use an electron microscope

Question 8

would the number be higher or lower (numerical) on electron microscope?

Answer 8

it would be lower since the resolution would be better

Question 9

the smallest object visible wit the human eye is ______ mm. What is it numerically?

Answer 9

0.10 mm, it would be 0.10 10^-3 meter

Question 10

a compound microscope can be used to view an object as small as ____, what is it numerically?

Answer 10

0.2 um, 10^-6 micrometer

Question 11

an electron microscope can be used to view objects as small as _____.

Answer 11

0.20 nm, 10^-9 nanometer

Question 12

True or false. Using the same magnification an electron microscope will also provide an image with a better resolution than a light microscope?

Answer 12

true

Question 13

elaborate on transmission electron microscope

Answer 13

used to examine internal structure
electron beams do not penetrate the thick cell well, which requires the cell to be cut in order to be viewed, this process is called thin sectioning
these thin sections must be stained before they can be viewed under the TEM

Question 14

used for extracellular structure and research purposes

Answer 14

scanning electron microscopy

Question 15

define what scanning tunneling microscopy

Answer 15

this is the most powerful of the electron microscopes
it is used to visualize atoms

Question 16

staining procedure: define it

Answer 16

1) a thin film of material called a smear which contains the microorganisms of interest is smeared on a slide
2) the sample is then fixed by passing through a flame
3) stain is then applied to the sample
(flooding, because we add a lot of stain)
4)the stain is removed from the sample by rinsing
5) the stained sample is now viewed under a microscope

Question 17

what does a gram stain determines?`

Answer 17

determines whether a bacterium is gram positive or gram negative

Question 18

on the stain procedure, passing through a flame will do what on the sample?

Answer 18

passing through a flame will dehydrate the sample

Question 19

what does amordant do?

Answer 19

amordant, intensify things such as iodine

Question 20

sticking to every cell is what kind of charge?

Answer 20

positive charge

Question 21

acid fast-chain define it

Answer 21

this stain binds strongly bacteria that contain a waxy cell wall component (mycolic acid).

Question 22

elaborate why mycobacterium tuberculosis and other members are positive but does not appear purple

Answer 22

they are gram positive but they do not appear purple, since they have another layer and what they put on that is myocolic acid, anything that has a charge is hydrophilic, it cannot do gram stain on mycobacterium since they have that outer layer

Question 23

The waxy cell wall of the mycobacterium retains carbol fuschin that is added, what does this do?

Answer 23

stick the wax to the hydrophobic, so this is also hydrophobic

Question 24

if positive for myobacterium it would appear to be pink and blue

Answer 24

True

Question 25

if not positive for myobacterium what color would it be?

Answer 25

methylene blue

Question 26

capsule stain:
this is a positive charged chromophore but it also uses a negative charge chromophore

Answer 26

true

Question 27

is safranin a positive stain?

Answer 27

it is.

Question 28

what color does endospore stain appear if they are a positive stain?

Answer 28

pink and green

Question 29

simple staining: name the purpose and the principle

Answer 29

purpose is to determine the morphology,
the principle: basic dye with net positive charge that can bind to the bacterial membrane that has a net negative charge
this is not a differential stain, therefore there isn’t a positive or negative

Question 30

negative staining : determine the purpose and principle

Answer 30

purpose: determine the morphology
principle: acidic dye with a net negative charge that is repelled by bacterial membrane that also has a net negative charge
positive/negative: is not a differential stain, therefore there is no negative or positive. we used nigrosin dye which gave a uniform black background. bacteria appeared as a clearing in the background bc they repelled the dy

Question 31

gram stain, determine the purpose, and the principle

Answer 31

purpose: to determine the gram stain as positive or negative
staining principle : positive or negative depends on the cell wall (peptidoclycan) thickness.
net positive crystal violet intercalates into cell wall, iodine act as a mordant to fix crystal violet in place. Crystal violet/iodine washed out of gram negative cell wall with acid alcohol. gram negative cells counter stained with simple stain safranin

Question 32

acid fast stain, principle and purpose

Answer 32

purpose is to identify the acid fast bacteria
staining principle: due to the presence of mycelia acid in the cell wall some bacteria most dyes including gram stain can’t penetrate the cell wall to reliable stain.
Heat is require to drive carbon funschin dye into the myocolic acid cell wall. slide is countered stained with the simple stain methylene blue.

Question 33

determine the purpose and principle of stain capsule

Answer 33

purpose is to stain capsule
principle: bacterial capsules are an important of differential stain to identify. capsule positive bacteria who are often virulent pathogens.

Question 34

what is energy in terms of resoltion

Answer 34

energy is wavelength

Question 35

high energy or shorter wavelength has the ability to what?

Answer 35

to destry your dna and cause cancer and incredibly destructable

Question 36

true or false: in scanning electron microscopy the specimen must be coated with a thin film of heavy metal

Answer 36

true

Question 37

true or false. IT DOES NOT HAVE TO BE PURPLE as a positive, but rather it depends on the chosen one, knowing the cell is negative is an important though

Answer 37

true

Question 38

this is a matter of yes or no, no specification, no differientation that comes off the simple stains

• they have stains, they have a charge and make them color whatever chromophore is

what is this?

Answer 38

simple stains

Question 39

when you add alcohol, in the gram stain procedure, if it’s a negeative infection, what will happen to the purple dye?

Answer 39

the purple dye washes out, why? because you are deoclorizing it

Question 40

is flagella a thin or thick cell

Answer 40

it is a thin stain, they are too small to be seen under light microscope without stain