Mic102 Quizzes to study for midterm1

hahahaha good luck

Which type of microscope would be the best choice for viewing very small surface structures of a cell?

A scanning electron microscope (SEM) is the best choice for viewing very small surface structures of a cell due to its ability to provide high-resolution images of the surface topography.

Upon hearing about electron microscopy, one of your classmates wants to go to the Electron Microscopy Core Facility at UC Davis to use transmission electron microscopy (TEM) to make a movie of flagellar movement in an individual bacterial cell. What problem might your classmate run into? 

 

The sample needs to be fixed, thus the bacteria will be dead and there will be no movement.

Lipopolysaccharide (LPS) is found:

 

in the outer membrane of Gram-negative bacteria

Archaea are similar to bacteria in many ways, but have some features that identify and distinguish them from bacterial cells. Which of the following is NOT one of those features.

 

The archaeal cell membrane has ester linkages with unbranched fatty acids

Why are microbes small? What is the key size constraint that unicellular microbes face? 

 

Surface to Volume Ratio

You are a clinical microbiologist working in a hospital. You have been given a sample from a patient that has a gram positive bacterial infection that has proven to be resistant to treatments. Which strain would you use to determine if this bacterium has waxy mycolic acids?

 

Acid Fast

I tell you that the bacterium I work with in my lab, Pseudomonas syringae, is a Gram-negative bacterium. What do you know based on just that information?

 

It spends a significant amount of its energy on synthesizing LPS

What statement is supported by this phylogenetic tree?

 

Archaea and Eukarya share a common ancestor

The gram positive cell wall is more complex than the gram negative cell wall.

False

In the lab, I grow a bacterium without a cell wall in a liquid that is isotonic with regard to the cell. That liquid has a solute concentration of 35%. If I place the cell in a different liquid that has a 1% solute concentration, what is the most likely outcome?

 

The cell bursts because water diffuses into the cell which has higher solute concentration.

The four most abundant elements in living matter are C, H, O, N. Why?

 

They have low atomic numbers and are thus light elements capable of forming strong bonds with other atoms to produce molecules.

Microbial cells build cell structures (such as flagella, membranes, etc.) from macromolecules, such as protein, lipids, and carbohydrates.

True

The high energy phosphate bond in ATP is the most energetic in the cell and that is why it is used as the energy currency of the cell.

False

Which of the following redox pairs will produce the most energy? Use the electron tower to inform your answer.

 

CO2/glucose [–0.43] and 1⁄2O2/ H2O [0.815]

The loss of an electron from a molecule is called:

Oxidation

A non-competitive inhibitor of an enzyme binds in active site.

False

In electron transport chains, the final electron acceptor is always oxygen.

False

The sequence of amino acids in a protein is called its

 

primary structure

The movement of electrons in a cell generally involves which atom?

Hydrogen

Nicotinamide adenine dinucleotide (NAD⁺/NADH) is the most common mobile electron carrier used in catabolism. NADH is the

 

reduced form because it has gained an electron.

Lysozyme can degrade archaeal cell walls.

False

Which statement about feeder pathways is not correct

 

Heterotrophs do not need feeder pathways because they consume organic molecules

Pathways of central metabolism are reversible if there are alternative enzymes that catalyze backward reactions (if standard enzymes cannot)

True

If a culture of E. coli you are tracking grows from 2 x 10³ cells/ml to 8 x 10⁷ cells per ml in 5 hours, what is the approximate generation time of your E. coli?

 

About 20 minutes

The TCA Cycle, Glycolysis, and Pentose phosphate pathway are all examples of:

 

Central pathways

Anoxygenic photosynthesis:

 

None of the answers is correct

(Must be cyclic

 

Must be non-cyclic

 

Produces Oxygen gas)

Glucose fermentation by some microbes can result in the accumulation of acids such as acetate and lactate in the medium. The accumulation of these acid byproducts is often toxic to the cell that makes them, but they do it anyway because fermentation is necessary to:

 

Continue ATP production by substrate-level phosphorylation

An bacterium that grows on Malate uses the central pathways as the diagram below shows. This bacterium also has a mutation that makes it so it cannot grow unless provided with the amino acid aspartate, which is made from the precursor metabolite oxaloacetate. The mutation would most likely occur in an enzyme of which central pathway?    

 

TCA Cycle

Glutamate is a key component to make sulfur containing building blocks.

False

There is no bacterial growth during stationary phase.

False