Microbio Exam 1

The scientist who proposed the germ theory of disease was...

Louis Pasteur

Which of the following statements describe viruses

they are dependent on their infected host

Parasitologists study...

Protozoans (pathogens)

Which of the following is a proper scientific name using nomenclature?

Giardia lamblia (italicized)

Ignaz Semmelsweis revolutionized surgical sterility when he suggested...

Handwashing

Measurement unit for a small virus

nm

If a microbiologist is studying a specimen under the light microscope and the background is dark, and the specimen is light. What kind of staining is this?

Negative staining

Which micrograph shows the surface of a specimen?

Scanning electron micrograph (SEM)

Using brightfield microscopy, which of the following amounts of magnification will we have to achieve in the lab in order to visualize a typical disease-producing bacterium?

1000x magnification

A microbiologist inoculates Staphylococcus epidermis and E. coli onto a culture medium. Following incubation, only the E. coli grows. What is the most likely explanation?

The culture medium must be selective.

The term that refers to the presence of flagella with multiple tails is...

Lophotrichous

Fimbrae

used primarily for adherence

The capsule differs from a slime layer because...

It is attached to the bacterial cell

Transpeptide linker of peptidoglycan

Gram positive cell wall

thick peptidoglycan layer

What color do gram positive prokaryotic cells stain?

Purple, due to thick peptidoglycan layer

Why do certain bacterial cells produce endospores?

protection of genetic material during harsh conditions

Which cannot be identified by gram stain because are acids fast?

Mycobacterium tuberculosis

Bacterial plasmids...

contain only nonessential pieces of DNA

Which statement regarding fungi is correct?

the group called "fungi imperfecta" contains the most human pathogens

Most protozoans are spread to others during which stage of their life cycle?

Cyst

The eukaryotic cell organelle that most resembles a bacterial cell is the...

mitochondria

In the eukaryotic cell, the site for protein synthesis is the...

both the cytoplasm and Rough ER

How do you determine a Helminth (worm) infection?

Find helminth eggs in the stool AND patient has a high eosinophil count

The process which results in a single bacterial cell yielding two identical daughter cells is called...

binary fission

Strict aerobe growth in Thioglycolate broth

know what this would look like

The phase of the bacterial growth curve in which the rate of multiplication is far less than the rate of cell death is the

death phase

A mesophile...

grows at body temperature

the movement of molecules from an area of high concentration to an area of lower concentration is called...

diffusion

Enzymes that are always present, regardless of the amount of substrate are...

constitutive enzymes

Substrate level phosphorylation

The enzyme-catalyzed formation of ATP by direct transfer of a phosphate group to ADP from an intermediate substrate in catabolism.

Competitive inhibition

substance that resembles the normal substrate competes with the substrate for the active site

Enzymes that are secreted by a cell to hydrolyze reactions are...

exoenzymes

A strictly fermentative bacterium produces energy by...

glycolysis only

In fermentation, NAD is recycled when the...

H removed from NADH is added to pyruvate to make an alcohol or acid

Which organisms undergo glycolysis?

Aerobic bacteria, Anaerobic bacteria, fungi, Aerotolerant anaerobes (all of the above)

The membrane embedded redox carrier molecules of the electron transport chain that are responsible for accepting and donating electrons are...

cytochromes

During aerobic cellular respiration, the final electron acceptor is...

oxygen

Which of the following statements are correct about the Krebs cycle...

It is a cyclic pathway, it breaks pyruvic acid down to CO2, strict anaerobes do not undergo the Krebs cycle, the majority of reduced NAD is produced in this cycle (all of the above)

Which of the following statements describe Prokaryotes?

They are measure in micrometers.

Mycologists study...

Fungi

How many meters are in 1 micrometer (um)?

10^-6 meters

Assume you are viewing a gram-stained field of red (pink) cocci and blue (purple) rods through the microscope. You can safely conclude that you have...

Two different species

In order to visualize a typical disease-producing bacterium using brightfield microscopy, which objective must be used?

100x objective with oil immersion

Peritrichous flagella

flagella that cover the surface of a cell

The capsule is similar to a slime layer in that...

both have antiphagocytic activity

A prokaryotic cell wall is...

gram-negative or gram-positive

Gram-negative stains...

purple b/c thin peptidoglycan layer

During which phase of the growth curve is the following statement TRUE: "Cell divisions afar outnumber cell deaths.

Log (exponential growth) phase)

An organism that grows optimally at body temperature (37 deg Celsius) is called a

Mesophile

What happens when a gram-positive bacterium, treated with penicillin, loses its cell wall and its placed in distilled water?

Water will move into the cell and the cell will lyse.

If A is the normal substrate for an active site, what would be the term for B that stops enzymatic reaction if it binds to the active site?

Competitive inhibitor

The most likely place where a bacterial endoenzyme participates in a chemical reaction is...

cytoplasm

Which of the following has the greatest amount of energy for a cell?

Glucose

What type of organism uses organic compounds (primarily glucose) for carbon and energy?

Chemoheterotroph

When enzyme action stops due to a buildup of end product, this control is called...

negative feedback

Feedback inhibition is best described as...

product binding to enzyme at a non-competitive site

What is involved in the step between glycolysis and the Krebs cycle?

Pyruvic acid is decarboxylated to Acetyl-coA

As the electron transport carriers shuttle electrons, they actively pump _____ into the outer membrane compartment setting up a concentration gradient called the proton motive force.

Hydrogen ions

In bacterial cells, electron transport takes place primarily in what part of the cell?

cell membrane

Why do microorganisms undergo fermentation?

To recycle the NADH to NAD+