Aerobic Respiration
What are the four steps that make up aerobic respiration?
Glycolysis, TCA cycle, Electron Transport Chain, Chemiosmosis
What are the three functions of the plasma membrane? Is the plasma membrane the cell wall of bacteria?
-Selectively-permeable barrier
-Site for protein attachment
-Involved in energy generation
NO THE PLASMA MEMBRANE IS NOT THE CELL WALL OF BACTERIA
Metabolism is classified as which two reactions?
Catabolic, anabolic
What are the three functions of pili?
Attachment, motility and conjugation
What are plasmids?
small, circular double-stranded DNA molecules that are dispersed throughout the cell cytoplasm. Theya re not typically needed for survival, but can provide advantages
What is the difference between substrate-level phosphorylation and oxidative phosphorylation?
Substrate-level phosphorylation - quick, direct, little ATP made
Oxidative Phosphorylation - slow, indirect, but lots of ATP made
What is the difference between penicillin and Lysozyme when it comes to bacterial cell wall? Which type of cell wall are they most effective against and why?
Penicillin: an antibiotic that weakens the cell wall by preventing proper formation of peptide cross-bridges in peptidoglycan.
Lysozyme: an enzyme that hydrolyzes the covalent bond between NAM and NAG.
Both are more effective against G(+) cells because G(-) has an outer membrane to protect and less peptidoglycan.
What are the two non-protein components that help enzymes perform their chemical reactions called?
General: Cofactors
-Coenzymes
-Metal Ions
What are the two movements that bacteria can do? Can you explain how each of them works?
Chemotaxis: directed movement based on chemical signals (towards attractants or away from repellents)
Run and Tumble: Run (forward movement), tumble (potential random changes in direction)
During aerobic respiration, what is the harmful molecule produced and what enzyme "de-toxifies" it.
Reactive oxygen species, Catalase
Oxidative Phosphorylation requires an electron transport chain, which requires a terminal electron acceptor. What molecules can be used as a terminal electron acceptor for anaerobic respiration?
Nitrate, Nitrite, Sulfate, Sulfite
What are some characteristics/reasons a bacteria cell has a cell wall?
Protection against osmotic lysis, and defense against predators
What happens to enzyme activity when there is high saturation aka a high substrate concentration?
Draw and explain a saturation curve
-There are too many substrates and not enough active sites, so the reactions levels off or plateaus
What are the 3 external structures that bacteria use for moltility?
A big molecule needs to travel from a low concentration on the inside of the cell to a high concentration outside of the cell and uses a transport protein to achieve this. What type of transport is this and is energy required?
Active transport and yes, energy is required
Explain fermentation
Glycolysis: glucose (oxidized) + NAD+ (reduced) -> pyruvate + NADH + little ATP
Pyruvate reduction: pyruvate (reduced) + NADH (oxidized) -> NAD+ "to be reused"
Which bacteria species did we talk about in lecture that lacks a cell wall?
Mycoplasma
A bacteria breaks down a large polysaccharide into smaller molecules. This reaction is considered spontaneous. What type of reaction is this?
Catabolic
What is the difference between chromosomes in bacteria vs Eukaryotes?
Bacteria have a single, circular chromosome while Eukaryotes have multiple, linear chromosomes
If you start with 300 cells, how many generations would it take to get to 38,400 cells?
7 generations
Explain aerobic respiration...what gets reduced and oxidized in each step? What are the products?
Glycolysis: 2 Glucose (oxidized) + NAD+ (reduced) -> 2 pyruvate + NADH + little ATP
TCA cycle: 2 pyruvate (oxidized) + FAD & NAD+ (reduced) -> NADH + FADH2 + CO2 + ATP
Electron Transport Chain: NADH & FADH2 (oxidized) + O2 (reduced) -> NAD+&FAD + H2O + proton motor force
Chemiosmosis: proton motor force (through ATP synthase) -> LOTS of ATP
Draw a G(+) and G(-) Cell Wall!
G(+) = Thick layer of peptidoglycan, teichoic acid
G(-) = peptidoglycan, periplasm, lipoprotein, outer membrane, porin, lipopolysaccharide (O polysaccharide and Lipid A)
After an attack from the immune system, a bacteria will try to rebuild itself, connecting small amino acids together to create a much larger protein. If this reaction was considered metabolic, it would also be considered nonspontaneous. But to do this, the bacteria must use energy. Even though this might not be considered a metabolic reaction, if it was, what type of reaction is this?
Anabolic
Clostridium and Bacillus
A bacteria cell is placed into a super salty solution (high salt concentration outside of the cell compared to inside), which causes all of the water to leave the bacteria cell. What type of solution is this and what will happen to the cell?
Water leaving the cell = hypertonic solution/effect and the cell will shrink due to water loss. This will cause plasmolyisis