Chapter 3 notes Flashcards
Define infection
a microbe that invades a human or other organism and causes illness and disease
What two things do growth of microbes include
–catabolic and anabolic process to increase cell size
–make more copies of itself
How do eukaryotes reproduce
sexually AKA meiosis
How do prokaryotes reproduce
binary fission
What does the parent cell of binary fission have
ribosomes and chromosomes
What are the steps of binary fission
- parent cell
- duplicating chromosomal DNA
- chromosomes separate and attach to cytoskeleton
- septum divides the cell in half
- two daughter cells
Out of the 2 daughter cells, which cell is the parent cell and which cell is the daughter cell
they’re both new parent
Equation for generation time
G = t/n
Define generation time
time per complete fission cycle of the population or doubling of population
growth can cause what with max rate of population
maxes out rate of binary fission
What is the equation for predicting population size over time
Nf = (Ni)2^n
What is the blood culture test
mix it with a medium, put sample in media to check for growth
Define incubated
grown under optimal conditions
Why do we streak plates
to isolate individual cells/colonies
CFU is the number of
visible colonies formed
What are the characteristics of H. infleunzae
gram negative
non motile coccobacillary
facultatively anaerobic
Is there blood agar growth in H. influenza
NO–BAP lack specific nutrients required for growth of H. influenza
What are the characteristics of S. Aureus
gram positive cocci
non motile
facultative anaerobe
is there growth in blood agar of S. aureus
yes beta
Characteristics of M tuberculosis
gram positive rod shaped
strict aerobic, acid fast
is there growth in blood agar of M. tuberculosis
yes, gamma
Characteristics of S. pneumoniae
gram positive
coccus
aerotolerant anaerobe
Is there blood agar growth in S. pneumoniae
yes alpha
Define blood agar
rich medium containing 5% sheep blood that can differentiate bacteria based on their hemolytic properties
Is blood agar complex media
yes
What are the effects on RBC of alpha hemolysis
partial destruction
What does alpha hemolysis look like on a plate
light colored green around colonies
What is the effect of beta hemolysis on RBC
total destruction
What will the plate look like with betal hemolysis
clear zones around colonies
What are the effects of gamma hemolysis to RBC
no damage
What does the plate look like with gamma hemolysis
no change on plate
What do we measure to measure growth over time
turbidity
What is the most accurate way to measure grwoth rate
viable plate counting
The real image is projected to the _______ where it is magnified again to form the ______ image
real; virtual
What are the visible wavelength of light
400nm to 750nm
Define total magnification
product of the separate magnifying powers of the two lenses
Electron waves are 100,000 times _______ than the waves of visible light
shorter
What is the magnification for light micro
between 40x and 2000x
What is the magnification for light micro
between 5,000x and 1,000,000x
In electron microscopes the image is due to
electron scattering
In light microscopes the image formation depends upon
light absorption in the object
Define simple stains
use one dye to stick to cells and give them color
Define negative stains
dye doesn’t color specimens but dries around its boundary forming a silhoutte
In spore stains what color is the spore and cell
spore green
cell red
What are the 3 differential stains
gram
spore
direct fluorescent
What is a structural stain
special stain to enhance details
What are the 2 structural stains
capsule stain
flagellar stain
