micro ch3 cont.

Sulfur & phosphorus can be obtained from inorganic sources only. True/False

False

Place the steps of sporulation in the correct order. A) Replication of DNA 2) Spore coat formation 3) In-folding of the plasma membrane to enclose a copy of DNA, forming forespore and septum 4) Maturation and release of endospore 5) Deposition of spore cortex 6) Engulfment of the forespore with a second membrane

Replication In-folding Engulfment Deposition Spore Maturation

How do spheroplasts and protosplasts differ? A. Spheroplasts retain the peptidoglycan but protoplasts do not. B. Spheroplasts retain their outer membrane but protoplasts do not. C. There is no difference; these terms are synonyms. D. Spheroplasts form from cocci and protoplasts form from bacilli.

Spheroplasts retain their outer membrane but protoplasts do not

Endospores represent a challenge to the fields of industrial and medical microbiology because A. they are resistant to harsh environments, thus allowing survival of endospore-forming organisms under conditions in which non-endospore-forming cells would not survive. B. endospore-forming organisms are often dangerous pathogens. C. endospores are significantly smaller than vegetative cells. D. 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.

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.

Zinc is a macro/micronutrient

macro

Bacterial and archaeal ribosomes are known as _____ ribosomes, based on their sedimentation coefficient. A. 50S B. 30S C. 80S D. 70S

70S

You have been studying the effect of a concentration gradient on the rate of transport of a nutrient into a bacterial cell. If a carrier protein is involved in the transport of this nutrient, which curve would you expect to see?

A

Which of the following processes can be used to bring nutrients into a cell against a concentration gradient? A. Active transport B. Facilitated diffusion C. Passive diffusion D. Active transport and facilitated diffusion

Active transport

The type III bacterial protein secretion machinery A. has a needlelike structure through which proteins are secreted. B. includes structural features that may be evolutionarily related to the basal bodies of bacterial flagella. C. is found in gram-negative bacteria. D. All of the choices are correct.

All of the choices are correct

Which of the following contribute to the environmental resistance of bacterial endospores? A. Spore coat B. Low water content of endospore C. Presence of calcium dipicolinate D. Lower pH E. All of the choices are correct.

All of the choices are correct

Which of the following is a characteristic of active transport? A. Saturable uptake rate B. Use of ATP or a proton gradient as a source of metabolic energy C. Can move materials against a concentration gradient D. All of the choices are correct.

All of the choices are correct

Order the following structures (layers) that a small molecule must pass through as it moves from outside of an encapsulated gram negative cell to the cytoplasm. Periplasm and Peptidoglycan Plasma membrane Capsule Outer membrane

Capsule, outer membrane, periplasm and peptidoglycan, plasma membrane

Which of the following is not considered a macronutrient? A. Carbon (C) B. Calcium (Ca) C. Potassium (K) D. Cobalt (Co)

Cobalt

Which bacterial structure may survive if temperatures applied during food preservation processes are too low? A. Flagella B. Endospores C. Plasma membranes D. Ribosomes

Endospores

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 A. facilitated diffusion. B. osmosis. C. passive diffusion. D. active transport.

Facilitated diffusion

Endospores are reproductive structures. True/False

False

The original differentiation of prokaryotes and eukaryotes was based on structures found in prokaryotes that are lacking in eukaryotes. True/False

False

__________ __________ are required organic compounds because they are essential cell components or precursors of such components that cannot be synthesized by the organism.

Growth factors

Which of the following is not part of the process by which an endospore transforms to become a vegetative cell? A. Germination B. Activation C. Induction D. Outgrowth

Induction

Which of the following is not considered a micronutrient? A. Manganese (Mn) B. Magnesium (Mg) C. Zinc (Zn) D. Copper (Cu)

Magnesium

The movement of molecules from an area of higher concentration to an area of lower concentration without the participation of specific carrier molecules is called A. facilitated diffusion. B. osmosis. C. passive diffusion. D. active transport.

Passive diffusion

Which of the following protects bacteria from lysis in dilute solutions and helps to determine their cellular morphology or shape? A. Plasma membrane B. Peptidoglycan C. Capsule D. Gas vacuoles

Peptidoglycan

__________ are carrier proteins embedded in the membrane that increase the rate of diffusion of specific molecules across selectively permeable membranes.

Permeases

All of the following are reasons why some scientists believe that the term "prokaryote" is a somewhat artificial designation and should be discarded except A. Some bacteria have internal membranous structures. B. Some bacteria have their genetic material enclosed within a membrane. C. Some bacteria have 80S ribosomes. D. Many bacterial have cytoskeletal elements.

Some bacteria have some 80S ribosomes

A strain of Neisseria gonorrhoeae has undergone a mutation and is no longer able to make pili. Predict the most likely outcome. A. The bacterial strain will no longer be able to transport certain sugars into the cell. B. The bacteria will become more virulent and will more readily establish infection. C. The bacteria will become more resistant to antibiotics. D. The bacteria will become less virulent and will not be able to readily establish infection.

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

Motile bacteria have been placed in an environment with a gradient of a chemical attractant. Which of the following behaviors would you predict? A. Bacteria will randomly switch back and forth between runs and tumbles. B. The bacteria will only exhibit runs away from the chemical. C. The bacteria will reduce tumbling frequency. D. The bacteria will reduce run duration in the direction of the chemical. E. The bacteria will both reduce tumbling frequency and increase run duration in the direction of the chemical.

The bacteria will both reduce tumbling frequency and increase run duration in the direction of the chemical

A pathogenic bacterial species has mutated and is no longer able to synthesize a capsule. Which outcome would you predict? A. The mutated bacteria will be more virulent. B. The mutated bacteria will not be able to cause disease as readily. C. The mutated bacteria will be protected from plasmolysis in hypertonic environments. D. The mutated bacteria will undergo osmotic lysis in hypotonic environments.

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

Predict the change in surface area and volume of a spherical cell if the diameter of the cell doubles: A. The surface area will increase by a factor of 4, while the volume will increase by a factor of 8. B. The surface area will increase by a factor of 8 while the volume will increase by a factor of 4. C. The surface area and volume will both increase by a factor of 4. D. The surface area will increase by a factor of 2 and the volume will increase by a factor of 4.

The surface area will increase by a factor of 4, while the volume will increase by a factor of 8

Which of the following is not true of bacterial plasmids? A. They can replicate independently of the chromosome. B. They may carry genes for drug resistance. C. They are required for host growth and/or reproduction. D. They may carry genes that enhance survival of the bacterium under certain conditions.

They are required for host growth and/or reproduction

Different transport systems for the same nutrient that are part of the same organism are usually regulated in different ways. True/False

True

Endotoxic shock, resulting from the release of endotoxin by bacteria infecting a patient, is only caused by Gram-negative bacteria. True/False

True

Nitrogen can be obtained from either organic or inorganic sources. True/False

True

Permease proteins that aid in the transport of nutrients resemble enzymes in their specificity for the substance to be transported. Each carrier is selective and will transport only a closely related set of substances. True/False

True

The extreme insolubility of ferric iron leaves little free iron available for transport into bacterial cells. True/False

True

The trace amounts of micronutrients needed by microorganisms are usually supplied as inadvertent contaminants in water and regular media components. True/False

True

The movement of molecules across a membrane from an area of lower concentration to an area of higher concentration with the expenditure of energy is called A. facilitated diffusion. B. osmosis. C. passive diffusion. D. active transport.

active transport

Nutrients can be concentrated from dilute solutions by A. pinocytosis. B. endocytosis. C. active transport and group translocation. D. electron transport.

active transport and group translocation

Export of flagellin subunits is mediated by A. an apparatus in the basal body of the flagellum that is related to the type II secretion pathway. B. the type I secretion pathway. C. an apparatus in the basal body of the flagellum that is related to the type III secretion pathway. D. None of the choices are correct

an apparatus in the basal body of the flagellum that is related to the type III secretion pathway

Twitching or gliding motility involves A. type IV pili. B. axial fibrils. C. movement of slime. D. both type IV pili and movement of slime can be involved in twitching or gliding motility.

both type IV pili and movement of slime can be involved in twitching or gliding motility

Sortase is a protein enzyme of bacteria that A. plays a key role in directing proteins to the periplasm. B. catalyzes covalent attachment of some surface proteins to peptidoglycan. C. directs secretion of proteins across the outer membrane. D. functions by transporting flagellum proteins to their extracellular site of assembly.

catalyzes covalent attachment of some surface proteins to peptidoglycan

A new protein has been described that transports a growth factor across the plasma membrane. This protein is most likely a/an: A. peripheral membrane protein, facing outward. B. peripheral membrane protein, facing the cytoplasmic side. C. integral membrane protein. D. cytoplasmic protein.

integral membrane protein

Copper is a macro/micronutrient

micro

Chemotaxis is a process by which bacteria A. move toward an attractant or away from a repellent. B. avoid phagocytosis. C. respond metabolically to the presence of autoinducer molecules. D. move on solid surfaces by means of type IV fimbriae.

move toward an attractant or away from a repellent

Which of the following is not a major class of growth factors? A. Amino acids B. Purines and pyrimidines C. Vitamins D. Nucleic acids

nucleic acids

The power used by most bacterial flagellar motors is produced by A. synthesis of glucose. B. ATP hydrolysis. C. proton motive force (PMF). D. All of the choices are correct.

proton motive force

Many bacteria facilitate the uptake of iron by secreting low molecular weight molecules, called ___________, to form complexes with the iron that can then be readily transported into the cell.

siderophores

Small organic molecules called __________ function as enzyme cofactors.

vitamins