Pre Checks

bacterial and archaeal ribosomes are known as ___ ribosomes, based on their sedimentation coefficient

70s

The protein coat surrounding the viral genome is called the

capsid

a complete virus particle is called

virion

What is the order of gram staining procedure

1. Primary stain with crystal violet for 1 minute. Water rinse 2. Iodine(mordant) for 1 minute, water rinse 3. Alcohol (decolorizer) for 10-30 sec water rinse 4. Safranin (counter stain) for 30-60 sec water rinse blot dry

Bacterial flagella are composedof three parts: the __________ body, which is embedded in the cell, the hook, and the ________, which is the longest part of the flagellum

Basal, filament

What is in the nuceloid

DNA

A fellow student carries out the Gram stain on a mixed culture containing Gram-negative rods and Gram-positive cocci. On completion he finds purple cocci and clear (no color) rods when viewing the prepared slide with a microscope. From the following, choose the best reason for these results.

The student forgot to add the counterstain

A fundamental difference between bacterial and archaea membranes is that

bacterial membranes are always compromised of phospholipid bilayers, whereas archaeal membranes can be bilayers or monolayers

Which of the following is not associated with prokaryotes

cilia

Which mechanism of nutrient acquisition is not seen in bacteria

endocytosis

Endospores represent a challenge to the fields of industrial and medical microbiology because _________.

endospores are resistant to harsh environments, thus allowing survival of endospore-forming organisms under conditions in which non-endospore-forming cells would not survive, and endospore-forming organisms are often dangerous pathogens

Although similar in function, the eukaryotic ribosomes is generally smaller and more complex than bacterial and archaea ribosomes

false

Bacterial viruses are so named because they have prokaryotic cell structures similar to bacterial hosts

false

Bacteria and archaea are typically fixed to slides by ________ while eukaryotes with subcellular structure, such as protists, are typically fixed by _________.

heat, chemicals

chemotaxis is a process by which bacteria

move toward an attractant or away from a repellent

You are studying a newly discovered prokaryotic microorganism and are attempting to determine whether it will be classified in the domain Bacteria or in the domain Archaea. All of the following would be helpful in making that distinction except _________.

presence or absence of double stranded circular DNA

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

After conducting the Gram Stain on a mixed culture containing Gram positives rods and Gram negative cocci, all the cells were purple in color. This is most likely because

the cells were not decolorized enough with alcohol or acetone

A pathogenic bacterial species has mutated and is no longer able to synthesize a capsule. Which outcome would you predict?

the mutated bacteria will not be able to cause disease as readily

A eukaryotic flagellum can either push a cell through a liquid environment or pull it through depending on the undulating pattern of movement.

true

Available evidence is consistent with the proposal that prion diseases are caused by infections proteins

true

Some archaeans are symbionts in animal digestive tracts

true