Chapter 3 quiz
Which of the following is/are true of capsules?
1. They prevent entry of many bacterial viruses. 2. They help bacteria escape phagocytosis by host cells. 3. They retain water and help prevent desiccation of the bacteria.
The cytoplasmic membrane of bacteria
1. retains the cytoplasm and its contents 2. acts as a selectively permeable barrier, allowing some molecules to pass while preventing the movement of others 3. is the major site of ATP synthesis in aerobes
Which of the following processes can be used to bring nutrients into a cell against a concentration gradient?
Active transport
Which of the following structures is NOT found in an endospore?
Capsule
Which bacterial structure may survive if temperatures applied during food preservation processes are too low?
Endospores
_________blank membranes allow some molecules to pass but not others
Selectively permeable
The concept of a prokaryote was first fully outlined in 1962 by
Stanier and Van Niel
Predict how the plasma membrane fatty acid composition would change as the temperature of the habitat of an aquatic bacterial species warms from 2oC to 15oC during the spring and summer months.
The percentage of saturated fatty acids would increase.
Which of the following does not contribute to packaging the relatively large bacterial chromosome into the nucleoid region of the cell?
Thymine-rich domains
The term used to describe bacteria that have a spherical shape is
coccus
Extracellular vesicles formed by Gram-positive cells are
cytoplasm surrounded by plasma membrane
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
A strain of Neisseria gonorrhoeae has undergone a mutation and is no longer able to make pili. Predict the most likely outcome.
he bacteria will become less virulent and will not be able to readily establish infection.
Proteins that are embedded within the cytoplasmic membrane and not easily extracted are called _________ proteins.
integral
Discovery of the bacterial cytoskeletal protein FtsZ provided an important link in the evolution of cells since
is was also discovered in mitochondria and chloroplasts
Although penicillin inhibits peptidoglycan synthesis, bacterial cells will continue to grow normally in the presence of penicillin in a(n) _________environment
isotonic
Square planar arrangement of cells that forms when round bacteria remain attached to each other during reproduction are called
tetrads
Structural differences between Gram-positive and Gram-negative bacteria are observed following the Gram-staining procedure since
the thick layer of peptidoglycan in Gram-positive bacteria is dehydrated during the alcohol step, thus acting as an impermeability barrier retaining the crystal violet/iodine complex
Twitching motility involves
type IV pili
The term used to describe bacteria that are shaped like curved rods is
vibrio