Microbiology and Microscopy
Types of electron microscopy.
Transmission electron microscope and scanning electron microscope.
The 4 types of bacterial morphology and what they look like.
Cocci/Coccus
Bacilli/Bacillus
Vibrio
Spirochete
What occurs during anaerobic respiration?
Fermentation
Name and describe the 4 stages of bacterial growth.
Lag phase ~ Bacteria prepare for growth
Log Phase ~ Exponential growth
Stationary Phase ~ Cells stop growing and turn on stress response (resources are running out)
Death Phase ~ Cells die exponentially
What is Delta G?
Delta G = Free energy, energy that is available to do work
Explain the Theory of Endosymbiosis
Mitochondria and chloroplasts are each derived from the uptake of bacteria. These bacteria established a symbiotic relationship with their host cell that eventually led to the bacteria evolving into mitochondria and chloroplasts.
The difference between symport and antiport, and the difference between passive and active transport.
Symport: two solutes travel in same direction via membrane protein
Antiport: two solutes travel in opposite directions via membrane protein
Passive: no energy input required; follows natural conc. gradient = diffusion (facilitated diffusion is same thing, but via membrane protein)
Active: energy input required; against natural conc. gradient. ABC transporters are an example of such
The types of media we discussed and their basic differences.
Complex (many growth factors) vs. Simple/minimal (only what is needed for growth)
Selective (uses specific growth factors to select for certain microbes over others) vs. Differential (with a growth indicator dye)
Explain each variable
N, N_0, n, g, t
N = Final # of bacteria
N_0 = Initial # of bacteria
n = # generations
g = Generation time
t = Time in minutes
Explain endergonic vs. exergonic
Endergonic = + Delta G requires energy pulled from surroundings
Exergonic = - Delta G releases energy into surroundings
The types of organisms classified as prokaryotic vs the organisms classified as eukaryotic and the cellular differences between the two.
Prokaryotic: Bacteria and Archaea (no membrane-bound organelles and no true nucleus)
Eukaryotic: Plants, Animals, Fungi and Protists (membrane-bound organelles and a true nucleus)
The outer layer found only on gram negative bacteria.
LPS layer, or lipopolysaccharide layer
Names of bacteria who prefer certain temperatures.
Psychrophile ~ -∞ - 20°C
Mesophile ~ 20°C - 45°C
Thermophile ~ 45°C - 80°C
Hyperthermophile ~ 80°C - ∞
Streptococcus pyogenes are often referred to as “flesh eating bacteria.” It can divide every 40 minutes at body temperature. Assume that you fall down and scrape your knee and get infected with five S. pyogenes cells.
After 24 hours, how many bacteria will be infecting your body?
N = 3.44 x 10^11
A cell hydrolyzes one mole of ATP, where the energy released by breaking the bond between the second and third phosphate group is 30.5 kJ mol⁻¹. The reaction takes place at a temperature of 310K, and the entropy change is 0.100 kJ mol⁻¹ K⁻¹.
What is the ΔG for ATP hydrolysis under these conditions?
ΔG = -.5
exergonic because ΔG is negative
Explain Pasteur's experiment and what is proved.
Two S-shaped flasks, one with a broken neck. He observed bacterial growth in the broken flask but not in the intact flask. Proved germ theory and that disease causing agents did not spontaneously appear.
Draw a bacterial cell with all the components and explain their function
Bacteria cell drawing must include: plasmid, chromosome, ribosome, cytoplasm, flagellum, endospore, capsule, cell wall, cell membrane, pili
The difference between strict vs facultative aerobes/anaerobes.
Strict aerobe/anaerobe = Microbe requires oxygen or requires no oxygen to live; can't function in the presence of what it doesn't use for respiration.
Facultative aerobe/anaerobe = Microbe can switch between being aerobic or anaerobic depending on its environment. (Facultative aerobe means prefers no oxygen, but can use it if needed)
You are studying a species of Clostridium botulinum. You know that the generation time is 2.75 hours. If you know you have 13 generations, how long has this colony been growing (in hours and minutes)?
35 hours 45 min
A microorganism hydrolyzes three peptide bonds during protein degradation. The bond energy for each peptide bond is 400 kJ mol⁻¹. The temperature during the reaction is 298K, and the free energy change (ΔG) for the hydrolysis of these peptide bonds is 115.3 kJ/mol.
Calculate the missing variable
ΔS = 3.64
Endergonic because ΔG is positive
Name some of the most important people in the world of microbiology and what they provided. (5)
Sir Robert Hooke - Compound microscope
Antonie Van Leeuwenhoek - Single-lens microscope
Florence Nightingale - Sanitation methods and germ theory
Louis Pasteur - Pasteurization and the disproving of the theory of spontaneous generation
Robert Koch - Pathogen postulates (cause and effect of virulent microbes)
How vancomycin and penicillin function as antibiotics and the sugars found in the peptidoglycan layer (cell wall) of a bacterial cell.
They inhibit cell wall or peptidoglycan synthesis, specifically the proteins found in the peptidoglycan layer (D-alanine and L-alanine) and the bonds between them (inhibiting transpeptidation). No cell wall=no structure=cell vulnerable=no cell
NAG and NAM (N-acetylglucosamine and N-muramic acid)
Correctly label the drawing.
A. Obligate aerobes
B. Obligate anaerobes
C. Facultative anaerobes
D. Aerotolerant anaerobes
E. Microaerophiles
You determine that a banana pie has 15,360 S. aureus cells in it. You know from previous research that S. aureus has a doubling time of 1.25 hours. If you know that the pie was made 12.5 hours ago, how many cells was the pie inoculated with?
N_0 = 15
A microorganism hydrolyzes three peptide bonds during protein degradation. The bond energy for each peptide bond is 432 kJ mol⁻¹. The temperature during the reaction is 289K, and the free energy change (ΔG) for the hydrolysis of these peptide bonds is 123.37 kJ/mol.
Calculate the change in entropy
Is this reaction endergonic or exergonic? Why?
Delta S = 3.935
Endergonic because Delta S is positive