Exam 1 Study Guide

Gram staining is a technique used to divide bacterial species into two groups based on differences in their DNA composition

False

Antiseptic surgery was pioneered by _______.

Lister

Which of the following individuals is credited for definitively disproving the theory of spontaneous generation using broth in swan-neck flask?

Louis Pasteur

The Gram-staining procedure is an example of __________.

differential staining

Match the the angle of the cone of light from the midpoint on the left, to the numerical aperture in an air medium to the right.

15 degrees- 0.26 20 degrees- 0.34 30 degrees- 0.5 60 degrees- 0.87

A 30× objective and a 20× ocular lenses produce a total magnification of ________.

600×

You study a bacterium that grows in very low-nutrient aqueous environments. Which type of transport mechanism is required to deliver nutrients from these environments where they are at a lower concentration than inside the cell?

Active transport

Which of the following structures cannot be used for attachment?

All of these can be used for attachment

If you wish to use immunofluorescence stain to differentiate between E. coli and Staphylococcus aureus, which of the following components of the fluorescent microscopy technique would be DIFFERENT between the two sample preparations so that you will be able to differentiate one organism from the other?

Antibodies

Which of the following proteins represents a coupled transport system where two molecules travel in the opposite direction?

Antiporter

After you boiled the media in the flask to kill every living form in the swan-neck flask, you let it sit in your room for a week. In which section of the flask (shown below) would you expect to find microbes? https://auburn.instructure.com/courses/1326598/files/164591198/download?download_frd=1

C

The figure below shows the four steps of Koch's postulate. The correct order of the postulates is https://auburn.instructure.com/courses/1326598/files/164591202/download?download_frd=1

C - A - D - B

What would the results of Pasteur's swan-neck flask experiment looked like if it supported the theory of spontaneous generation?

Chemicals in the broth came together to form living organisms.

Which of these series arranges microbes from smallest to largest?

Ebola virus → E. coli → Red Blood Cell → Thiomargarita namibiensis

The lipopolysaccharide (LPS) that is found in the outer membrane of Gram-negative bacteria is also known as _________.

Endotoxin

The phospholipid bilayer of Archaea possess what type of bond linking them?

Ether

A student is observing microorganisms in a sample of pond water. One organism of interest has an obvious nucleus,small oval structures containing a green pigment, and does not appear to be motile. In which of the following groups would this microbe most likely be classified?

Eukaryotes (Algae)

The movement of molecules across a membrane from an area of higher concentration to an area of lower concentration with the use of a carrier molecule embedded in the membrane is called _________.

Facilitated diffusion

Cell division is deemed complete once all the DNA has been replicated.

False

The relationship between specific bacteria and specific diseases was first demonstrated by Pasteur.

False

Robert Koch is a German physician known for his contribution to medical microbiology. When he proposed his four postulates, Robert Koch considered which of the following factors?

Infectious bacteria

Koch's postulates would work to identify the following organisms as a cause of disease EXCEPT?

Influenza virus

Which of the following is FALSE about bacterial outer membrane?

It is composed of a phospholipid bilayer.

Who is credited with developing and documenting the first vaccination procedure against smallpox?

Jenner

What is one difference between Acid Fast and Gram stain?

Only Acid fast require heating while staining

Your research group is performing research on aquatic microbial life in a local pond. Your assignment is to take images of live microorganisms showing their organelles. Which type of microscope would you use to achieve this?

Phase-contrast microscope

What is NOT true regarding proteins that are embedded within the cell membrane?

Prevents secretion outside of the cell

Cells with a relatively simple cell morphology that do not have a true membrane-delimited nucleus are called _______.

Prokaryotes

A strain of Neisseria gonorrhoeae has undergone a mutation and is no longer able to make pili. Predict the most likely outcome.

The bacteria will become less virulent and will not be able to readily establish infection.

You are Gram staining the highly infectious organism Mycobacterium tuberculosis but are unable to view the cells under the microscope. Why?

The organism contains mycolic acids in its cell wall and requires a different stain

Which of the following statements about prokaryotic flagella is correct.

They are found in both Gram-positive and Gram- negative bacteria.

All of the following are reasons we perform Gram staining EXCEPT?

To determine tuberculosis infection

Gram positive cocci that is known to form septums in random planes appear in cluster-like arrangement under microscopy.

True

Invisible living creatures were thought to exist and cause disease long before they were ever observed.

True

Light rays are refracted (bent) when they cross the interface between materials with different refractive indices.

True

Mimivirus has a size of 390 nm in length, and 220 nm in diameter. Can this virus be resolved with a compound light (bright field) microscope?

True

Resolution improves when the wavelength of the illuminating light decreases.

True

The endosymbiotic hypothesis is generally accepted as the origin of eukaryotic organelles.

True

The majority of prokaryotic organisms possess a 70S ribosome.

True

Who of the following was the first to observe and accurately describe microorganisms?

Van Leeuwenhoek

A simple way to observe microbes is to place them in a drop of water on a slide with a coverslip. This technique is called ________________ preparation.

Wet mount

The ribosomal RNA studies that led to the division of prokaryotic organisms into the Bacteria and the archaea were begun by ________.

Woese

In the Gram-staining procedure, the primary stain is __________.

crystal violet

In the Gram-staining procedure, the decolorizer is __________.

ethanol or acetone

Louis Pasteur is a French microbiologist who is credited for his MANY contributions to the field of microbiology. Which of the following is NOT an accomplishment of Louis Pasteur?

he identified the cause of anthrax as a bacterium

In the Gram-staining procedure, the mordant is __________.

iodine

After the decolorizer has been added, Gram-positive organisms are stained __________ and Gram-negative organisms are stained __________.

purple; colorless

Immersion oil can be used to increase the resolution achieved with some microscope lenses because it increases the __________ between the specimen and the objective lens.

refractive index

Small internal cell structures that are measured in nanometers (nm) are best visualized using a _________.

transmission electron microscope