Microbiology Chapter 3: Bacterial Cell Structure

Réussis tes devoirs et examens dès maintenant avec Quizwiz!

LPS is composed of ___.

- Sugars - Lipids

Phosphorelay systems (PTS) are often ___.

Absent in aerobic bacteria

What term is used to describe the asymmetric character of the lipids found in membranes?

Amphipathic

Some bacteria can make a dormant structure which is resistant to many very hostile environments called a(n) ___.

Endospore

Enzymes that are secreted outside the cell to principally degrade large compounds so they can be imported are called ___.

Exoenzymes

Compounds that must be acquired from the environment for cell survival are called ___.

Growth factors

The ___ is a structure found in all life and is responsible for protein synthesis.

Ribosome

Compared facilitated diffusion and passive diffusion when solute concentrations are reduced.

They both diffuse slower

T or F: Bacteria have a cytoskeleton

True

The core polysaccharide of LPS is composed of ___.

about 10 sugars

Bacterial magnetosomes function to ___.

determine orientation (direction)

Many bacteria secrete ___ outside of the cell to capture substances like iron and allow those substances to be translocated into the cell.

siderophores

When facilitated diffusion's red-line becomes horizontal, this indicates ___.

solute saturation of carrier molecules

Identify the components of the bacterial ribosome.

- 55 proteins - 5S rRNA - 23S rRNA - 16S rRNA

Fimbriae can ___.

- Aid in attachment to surfaces - Aid in the uptake of DNA (type IV) - Aid in motility (type IV)

Identify the components of the cell wall fro gram-positive bacteria.

- Amino acids - NAG - NAM - Glycine crossbridge - Teichoic acids

Identify some characteristics of teichoic acids.

- Can be directly bound to peptidoglycan - Can be lipid-modified (lipoteichoic acid) - Negatively charged

Macroelements would include which of the following?

- Carbon - Sulfur - Oxygen - Hydrogen - a few others

In what ways are bacteria DIFFERENT from animals cells?

- Cell wall - Cellular arrangement - Size

Identify any of the following that has an association with the bacterial plasma membrane.

- Cellular respiration - Photosynthesis - Import/export proteins

Identify similarities between eukaryotic and bacterial cell membranes.

- Contains integral proteins - Composed of primarily lipids - Bilayer of lipids - Fluid - Contains peripheral proteins - Selectively permeable Composed of phospholipids

Sex pili are a bid different from fimbriae due to ___.

- Found in Eukaryotes - Determine conjugate (something)

Which type of bacterial motility often uses type IV pili?

- Gliding motility - Twitching motility

Identify the functions of the bacterial cytoskeleton.

- Involved in cell division - Involved in cellular shape - Involved in the localization of specific proteins within the cell

Identify the characteristics associated with bacterial caboxysomes found often in cyanobacteria.

- Location for CO2 fixation - Polyhedral protein coat - Type of inclusion body - Carbonic anhydrase

Indicate possible triggers for endospore production.

- Low levels of nutrients - Becoming too cold - Becoming too hot - Presence of hostile chemicals

Identify the functions of a lipopolysaccharide.

- Makes a permeability barrier - Contributes to the negative charge of the cell - Stabilizes the outer membrane - Protects from environmental toxins (and immunological factors)

Match the following terms with the correct description. Monotrichous; amphitrichous; lophotrikhous; peritrichous.

- Monotrichous: single flagellum - Amphitrichous: flagella located at both ends of the cell - Lophotrichous: a cluster of flagella at one or both ends of the cell - Peritrichous: flagella scattered about the entire surface of the cell

Ribosomes are composed of ___.

- Nucleic acid - Protein

Match the following cytoplasm components based on the best description. Nucleoid; ribosome; plasmid; inclusion body; cytoskeleton.

- Nucleoid: composed of DNA and protein - Ribosome: composed of RNA and protein - Plasmid: typically circular DNA that is not always needed - Inclusion body: often an aggregate of materials surrounded by protein - Cytoskeleton: network for protein polymers

Which of the following substances may use Passive Diffusion for movement across a membrane?

- Oxygen - Carbon dioxide - Water

Identify the characteristics associated with bacterial carboxysomes found often in cyanobacteria.

- Polyhedral protein coat - Type of inclusion body - Carbonic anhydrase - Location for CO2 fixation

The functions of the cell wall include:

- Protection from toxic substances - Protection from osmotic stress - Defines cell shape

The cytoplasmic membrane of bacteria ___.

- Retains the cytoplasm and its contents. - Acts as a selectively permeable barrier, allowing some molecules to pass while preventing the movement of others. - Is the major site of ATP synthesis in aerobes.

Teichoic acids could be composed of ___.

- Ribitol - Glycerol - Phosphate groups

Which of the following is a characteristic of active transport?

- Saturable uptake rate - Use of ATP or a proton gradient as a source of metabolic energy - Can move materials against a concentration gradient

Identify any of the following that describes typical plasmids.

- Small relative to the chromosome - Most known plasmids are circular - Replicates fairly independently - Composed of DNA

Identify all the general SIMILARITIES between Bacteria and Archaea.

- Smaller than Eukaryotes - Lacking membrane bound organelles

Identify and growth factors listed below.

- Some amino acids - Vitamins - Some nucleotides

Identify the different motility traits founding bacteria that use flagella.

- Spinning (clockwise of CCW) - Corkscrewing (causing the cell body to spin)

Identify the functions of bacterial inclusions.

- Storage - Reduce osmotic pressure

Identify the method for motility used by some bacteria.

- Swarming (flagella) - Twitching (pili) - Corkscrew movement (spirochete have axial flagella that allows the bacterial cell to rotate in a corkscrew manner) - Gliding - Swimming (flagella)

Match the following examples of taxis with their definitions. Thermotaxis; phototaxis; osmotaxis; aerotaxis.

- Thermotaxis: stimulant=temperature - Phototaxis: stimulant=light - Osmotaxis: stimulant=osmotic pressure - Aerotaxis: stimulant=oxygen

Which of the following is/are true of capsules?

- They help bacteria escape phagocytosis by host cells - They retain water and help prevent desiccation of the bacteria - They prevent entry of many bacterial viruses.

Bacterial twitching motility will often require ___.

- Type IV pili - Slime production

List the order of endospore activation to a vegetative cell.

1. Activation 2. Germination 3. Outgrowth

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.

1. Capsule 2. Outer membrane 3. Periplasm and Peptidoglycan 4. Plasma membrane

Place the following in order to describe the gram-staining process.

1. Crystal violet treatment 2. Iodine treatment 3. Alcohol treatment 4. Safranin treatment

Organize the structure of the flagella starting with the top and working down.

1. Filament 2. Hook 3. Basal body

Which of the following describes the average size of a rod bacterium like Escherichia coli?

1.1-1.2 micro meters wide and 2-6 micro meters long

Match the following bacterial ribosome relationships. 16S rRNA 23S rRNA & 5S rRNA 21 Proteins 34 Proteins

16S rRNA - small RNA-component subunit 23S rRNA - large RNA-component subunit 21 proteins - small protein-component subunit 34 proteins - large protein-component subunit

When was the Gram-Staining process introduced?

1884

The approximate dimension of fimbriae are ___.

3 to 10 nm in diameter and up to several micro meters long.

In gram-negative bacteria, the periplasmic space is ___ wide.

30 to 70 nm

How thick is a common plasma membrane?

5-10 nm

Bacterial ribosome are composed of two subunits, the ___ and the ___.

50S and 30S

Substances of approximately ___ or smaller can pass through porin proteins in the outer membrane.

600 daltons

Sphereoplasts are formed when ___.

A bacterial cell is treated with lysoszyme

Bacterial hopanoids can be described as ___ because the originate from steroids.

A type of sterol

ATP-binding cassette transporters are also known as ___ transporters.

ABC transporters

The use of ATP to power the movement of substance across a membrane is commonly referred to as ___ transport.

Active

Nutrients can be concentrated from dilute solutions by ___.

Active transport and group translocation.

___ is used to decolorize bacterial cells during the gram-staining process.

Alcohol

Bacterial inclusions are ___.

An aggregate of materials within the cell

What sort of bacteria would you typically find phosphorelay systems (PTS) working?

Anaerobic

The membrane-bound organelle called the ___ is observed in some members of the phylum Planctomycetes and alls for anaerobic ammonia oxidation.

Anammoxosome

During secondary active transport, when ions move opposite to the movement of a substance this is termed ___.

Antiport

Which of the following organisms appears to blur the lines between prokaryotes and eukaryotes?

Archaea

Which of the following organisms groups can have cell walls composed of peptidoglycan?

Bacteria

Match the following relationships. Bacterial cell membrane; Eukaryotic cell membrane.

Bacterial cell membrane: hopanoids Eukaryotic cell membrane: cholesterols

What compound links the outer membrane to the cell wall of gram-negative bacteria?

Braun's lipoprotein

Many bacterial gas vacuoles are principally used for ___.

Buoyancy

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

C. integral membrane protein.

The well molecularly-organized ___ is located outside of the cell membrane and is well known to aid in the resistance to phagocytes.

Capsule

Match the following according to their relationships: Capsule; slime layer; S-layer

Capsule: organized sugar layer Slime layer: unorganized sugar layer S-layer: organized protein layer

What is the name of a structure found in cyanobacteria which is about 100nm across and is the location for enzymes responsible for CO2 fixation?

Carboxysome

Sortase is a protein enzyme of bacteria that ___.

Catalyzes covalent attachment of some surface proteins to petidoglycan.

All bacterial layered structures from the cell membrane out are collectively referred to as the ___.

Cell envelope

The ___ is defined as the plasma membrane and all surrounding layers external to it.

Cell envelope

Which of the following structures necessitates the production of exoenzymes?

Cell membrane

Which of the following is considered true regarding cell membranes?

Cell membranes are a heterogeneous mixture of complex compounds floating in a "sea" of lipids

As a cell gets larger, which attribute increases fastest/most?

Cell volume

A strongly distinguishing characteristic of Domain Bacteria, almost all bacteria have a(n) ___ outside the cell membrane.

Cell wall

In most bacterial cells, the ___ is the next structural layer, surrounding the cell and extending out from the plasma membrane.

Cell wall

Which structure of bacteria dictates the outcome of gram-staining?

Cell wall

Match the following common structure of bacteria with their function. Cell wall; cell membrane; capsule; ribosomes.

Cell wall - resistance to osmotic stress Cell membrane - selectively permeable barrier Capsule - Protective layer verses dehydration and sometimes aids in adherence to surfaces Ribosomes - responsible for protein synthesis

Which of the following describe proteins that aid in the translocation of materials across a membrane?

Channels and carriers

Chemotaxis requires a stimulating molecule to bind (trigger) the ___.

Chemoreceptor

The movement of a cell toward or away from a specific CHEMICAL stimulant is called ___.

Chemotaxis

Most bacteria have ___ chromosomes(s).

Circular

Which of the following components of an endospore is composed of highly crosslinked protein?

Coat

Which of the following components of an endospore is primarily resistant to lysozyme?

Coat

Connecting the lipid A of LPS to the O antigen is the ___.

Core polysaccharide

The process of spontaneously losing a plasmid or purposefully forcing a plasmid to be lost is called ___.

Curing

The process of spontaneously losing plasmid to purposefully forcing a plasmid to be lost is called ___.

Curing

To better understand the genome of Borrelia burgdorferi, a researcher decides to force the bacterium to lose plasmids. This process of plasmid loss is called ___.

Curing

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?

Curved

The most inclusive term to describe the contents within the plasma membrane is ___.

Cytoplasm

The network of proteins that crisscross the cytoplasm of eukaryotic cells and give structural strength and in some instances, movement are called the ___.

Cytoskeleton

Which bacterial structure may survive if temperatures applied during food preservation processes are too low?

Endospores

Which of the following best describes why the food industry has trouble dealing with human pathogens that can make endospores?

Endospores are resistant to many cooking techniques

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

Endotoxin

The "energy-free" movement of molecules across a membrane with the aid of a transporting protein is called ___.

Facilitated diffusion

T of F: Plasmids replicate only when the bacterial chromosome replicates.

False

T or F: If you remove the peptidoglycan layer from a Gram-positive cell, it would still stain purple with a Gram stain.

False

T or F: Sedimentation coefficients are proportional to the molecular weight of a particle and are not affected by the volume and shape of the particle.

False

What term is used to describe long chains of cells found in cyanobacteria?

Filamentous

Typical numbering in the 100's to 1000's, the thin and relative to the cell, short hair-lie projections extending from the bacterial cell are called ___.

Fimbriae

___ is a word used often interchangeably with pili.

Fimbriae

Which of the following is the typical motility structure of bacteria?

Flagella

In most bacteria, the proton motive force directly will power ___.

Flagella movement

This bacterial cell image shows several long tube-like structures called ___ and hundreds of hairlike projections called ___.

Flagella; Fimbriae

Drs. Singer and Nicholson proposed a model to describe how lipids behave in a membrane called the ___ model.

Fluid Mosaic

Which of the following best describes the bacterial cell membrane?

Fluid mosaic

How many basal body rings are found in gram-negative bacteria?

Four

Which of the following is an E. coli cytoskeletal protein that is well known to be involved in cell division during bacterial binary fission?

FtsZ

Common bacterial micro compartments composed of a protein shell often contain ___.

Functioning enzymes

Common bacterial microcompartments composed of a protein shell often contain ___.

Functioning enzymes

What term is used the outer sugary coating that encompasses the terms of capsule and slime layers?

Glycocalyx

Lipopolysacchararides are found in ___ bacteria.

Gram-negative

Lipopolysaccharides are found in ___ bacteria.

Gram-negative

___ bacteria have an inner membrane and an outer membrane.

Gram-negative

Technoic acids are common among ___.

Gram-positive bacteria

You discover a new transport system used by a newly discovered bacterial species. The sugars that are transported using this system are phosphorylated as they enter the bacterial cell. You would describe this transport system as a(n) _____.

Group translocation

Which of the following describes the phosphotransferase system (PTS)?

Group translocation transporter

During facilitated diffusion, substances move from a ___ concentration of molecules to a ___ concentration of molecules.

High to low

The heads of a phospholipid are said to be polar in nature which could also be said to be ___ in regards to its affinity toward water.

Hydrophilic

The tails of a phospholipid are said to be nonpolar in nature which could also be said to be ___ in regards to its affinity toward water.

Hydrophobic

What sort of characteristic must be found regarding any proteins that extend through a membrane? Answer: The protein must have ___.

Hydrophobic regions to extend through the membrane with hydrophilic regions interacting with the membrane exterior

A mycelium consists of a network of long branched ___.

Hyphae

Which describes a major difference between integral proteins (IP) and peripheral proteins (PP)?

IP are difficult to disassociate from membranes

In the late 1800's, scientists discovered aggregates of materials within bacterial cells (not membrane-bound) and called them ___.

Inclusions

Which of the following would make an excellent transported proteins for materials to cross the plasma membrane?

Integral proteins

During gram-staining, ___ will bind to crystal violet and keep it from leaving the cell during the alcohol step.

Iodine

What stop occurs between the crystal violet step and the alcohol step during gram-staining?

Iodine step

Almost all microbes require ___ for use of cytochromes and many enzymes.

Iron

What happens to the "parent cell" at the end of sporulation?

It is destroyed

How does the endospore get its second membrane?

It is engulfed by the parent cell

If the difference between two concentrations of solutes drop then what happens to facilitated diffusion?

It slows down

The location of the cell wall is ___.

Just outside the plasma membrane

Which of the following compounds is well-known to protect gram-negative bacteria from various environmental toxic substances?

LPS

Which of the following polymers is composed of lipids and sugars?

LPS (lipopolysaccharide)

What is the most common trigger for sporulation?

Lack of nutrients

Bacterial micro compartments (a type of inclusion) are composed of ___.

Large polyhedrons of proteins

The bacterial chromosome is ___ (relative to its cell volume) and therefore it ___.

Large; requires organized packaging

Flagella are ___ compared to fimbriae.

Larger

The ___ component of the LPS can act as a toxin to people infected with gram-negative bacteria.

Lipid A

Which component of LPS anchors the compound in the outer membrane of the gram-negative bacteria?

Lipid A

___ is a term used to specifically describe a cell bursting open.

Lysis

___ is a well known eukaryotic enzyme capable of degrading peptidoglycan layers.

Lysozyme

Elements such as carbon, oxygen, hydrogen, nitrogen, sulfur and phosphorus are considered ___.

Macronutrients

Which of the following is NOT a characteristic of the plasma membrane. A. Selectively permeable B. Contains proteins C. Maintain cell shape D. Composed of a phospholipid bilayer

Maintain cell shape

Zinc, cobalt, molybdenum, nickel, and copper are examples of ___.

Micronutrients

The flagella arrangement that consists of a single flagellum at the end of a cell is termed ___.

Monotrichous

What is the name given to the two sugars found repeated in peptidoglycan?

N-acetylmuramic acid N-acetylglucosamine

What are abbreviated names for the two sugars found repeated in peptidoglycan?

NAG - N-acetylglucosamine NAM - N-acetylmyramic acid

If in an isotonic environment, will penicillin typically kill a bacterium?

No

Typically plasmids are considered ___ for bacterial survival.

Not absolutely necessary

The packaging (coiling) of bacterial chromosomes uses ___.

Nuceoid-associated proteins

Which of the following structure is NOT found in common between plants and bacteria? A. Nucleus B. Cell wall C. Ribosomes D. Cell membrane

Nucleus

Lipopolysaccharides are composed of lipid A, core-polysaccharide and the ___.

O antigen

The ___ is the LPS component responsible for stimulating an antibody response in people infected with gram-negative bacteria.

O antigen

The ___ is the LPS component responsible for stimulating and antibody response in people infected with gram-negative bacteria.

O antigen

Which of the following components of LPS extends outward from the cell?

O antigen

Most bacteria have ___ chromosome(s).

One

Bacterial inclusions are composed of ___.

Organic or inorganic materials surrounded by protein or liprotein

The Braun's lipoprotein links the ___ to the ___ in gram-negative bacteria.

Outer membrane to the cell wall

Substances like oxygen, carbon dioxide and water would move across a bacterial cell membrane by ___.

Passive diffusion

The unaided (no protein involved), energy-free diffusion of molecules across a membrane is called ___.

Passive diffusion

Which of the following best describes the organization of compounds embedded in the cell membrane?

Patchwork (not evenly dispersed)

The ___ interbridge is a linkage found in many gram-positive bacteria that links polymers of peptidoglycan together.

Peptide or Glycine or Pentaglycine

Teichoic acids (not lipteichoic acids) are anchored to ___.

Peptidoglycan

The bacterial cell wall is composed of a complex of sugars and amino acids that is collectively referred to as the ___ layer.

Peptidoglycan

Gram-negative bacteria have a(n) ___ space between the inner membrane and the outer membrane.

Periplasmic space

Polyphosphate granules are used to most often store ___.

Phosphate

The minimum unit of a cell membrane is the ___.

Phospholipid

The transfer of phosphate form PEP to an incoming molecule involves several proteins working together and this is an example of ___.

Phosphorelay system

The transfer of phosphate from PEP to an incoming molecule involves several proteins working together and this is an example of ___.

Phosphorelay system

Match the following relationships. Pink; Purple.

Pink: Gram-negative Purple: Gram-positive

A(n) ___ is a layer of lipid macromolecules that surround the cell's cytoplasm.

Plasma membrane

Significantly smaller, double-stranded and often circular pieces of DNA typically found in addition to the bacteria chromosome are called ___.

Plasmids

In hypertonic solutions, a cell could potentially shrivel up and this is called ___.

Plasmolysis

Bacterial shapes that do not fit the typical categories of bacillus, coccus or spirals are called ___ in shape.

Pleomorphic

Match the following relationships. Polar; Nonpolar.

Polar - hydrophilic Nonpolar - hydrophobic

What charge does crystal violet have?

Positive

Which of the following describe ATP-binding cassette transporters?

Primary active transport

Which of the following uses ATP to move substances across a membrane?

Primary active transport

Due to structural complexities found in some bacteria and some archaea, which of the following "pairings" is in dispute?

Prokaryotes are very different from Eukaryotes

The bacterial nucleoid is composed of ___.

Protein and DNA

Most bacterial flagella are powered by a "___ motive ___".

Proton motive force

Which of the following bacterial structures is responsible for protein synthesis?

Ribosome

When a bacterium is moving in a constant direction, then it is said to be in a ___ state.

Run

Which of the following is generally composed of protein?

S-Layer

Which of the following can form (oligomerize) spontaneously from simple subunits?

S-layer

Transportation of molecules across the membrane using an additional solute is termed ___.

Secondary active transport

When an ion gradient assists the movement of a substance across a membrane, this is called ___.

Secondary active transport

Which of the following transport systems completely relies on solute concentration gradients of a secondary substance to power the translocation of materials across a membrane.

Secondary transport

To overcome the difficulties of brining ferric iron into the cell, bacteria produce ___ to facilitate this process.

Siderophores

Gliding bacteria often have ___ which aid in their motility.

Slime layers

Which of the following describes the controversy concerning organisms categorized as prokaryotes?

Some newly discovered organisms share eukaryotic features and typical prokaryotic features.

For bacterial motility, the major difference between run and tumble is ___.

Spin direction of the flagella

Bacterial flagella swim by ___.

Spinning around and around like propeller

Which of the following bacterial shapes can reach 500 micro meters in length?

Spirochetes

Which of the following contribute to the environmental resistance of bacterial endospores? A. Spore coat B. lower water content of endospore C. presence of calcium dipicolinate D. lower pH

Spore coat

The process of endospore formation is collectively called ___.

Sporulation

Match the following terms with the best description. Sporulation; Germination.

Sporulation: hostile conditions Germination: moderate conditions

What term is used to describe the cell-arrangement composed of spherical cells found in clumps, like a bunch of grades (grater than two cells)?

Staphylococcus

Bacterial cell membranes lack ___ compared to eukaryotic cell membranes.

Sterols

What term is used to describe the cell-arrangement composed of spherical cells linked in a chain (e.g., several cells in a single row)?

Streptococcus

In general, peptidoglycan is composed of ___.

Sugars and amino acids

Which of the following best describes why bacterial cells are so small?

Surface area to volume ratio

During secondary active transport, when ions move parallel to the movement of a substance, this is termed ___.

Symport

Lipids in membranes arrange ___.

Tail to tail (hydrophobic tail to hydrophobic tail)

A repeating strand of glycerol (or ribitol) and phosphate groups is called ___.

Teichoic acid

Which compounds typically gives gram-positive bacterial cell walls their net-negative charge?

Teichoic acids

Gram-negative bacteria typically stain pink predominantly due to ___ and ___.

The alcohol step; Safranin

Motile bacteria have been placed in an environment with a gradient of a chemical attractant. Which of the following behaviors would you predict?

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

Bacterial sporulation can be defined as ___.

The generation of an endospore

One distinguishing characteristic of group translocation is ___.

The molecules transferred are chemically altered

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 describes the "protoplast"?

The plasma membrane and all the structures within the plasma membrane

Which portion of the flagella is spinning during the swimming motion?

The whole thing

Endospores are very resilient to hostile conditions because ___.

They have many layers of proteins, lipids, and other complex compounds to protect them

The cell wall of a gram-negative bacteria and considerably ___ compared to gram-positive bacteria.

Thinner

In many gram-negative bacteria, what is the role porin proteins?

To facilitate the movement of compounds like glucose across the outer membrane

Ribosomes are involved with which of the following processes?

Translation

The metabolic process of mRNA being used as the template for the manufacture of protein is called ___.

Translation

Proteins characterized as "channels" and "carriers" are ___.

Transport proteins

T or F: Sterol-like molecules called hopanoids are thought to be important for the structural integrity of many bacteria because of their suspected role in membrane stabilization.

True

T or F: Endotoxic shock, resulting from the release of endotoxin by bacteria infecting a patient, is only caused by Gram-negative bacteria.

True Endotoxin: gram-negative bacteria Exotoxin: gram-positive bacteria

The arrow labeled "A" indicates where a bacterium is changing direction and this is called a(n) ___. The arrow labeled "B" indicates where a bacterium is moving forward and is called a(n) ___.

Tumble; Run

How many lipid layers are found in a bacterial plasma membrane? (Note: a lipid layer consists of a series of phospholipids arranged side to side with hydrophilic heads all facing one direction and hydrophobic tails facing the other direction)

Two

Lipid A of LPS is composed of ___.

Two glucosamine sugar derivatives

Twitching motility involves ___.

Type IV pili

Which best describes how endospores can be resistant to UV radiation?

UV light cannot easily penetrate the many layers; proteins, lipids and other materials that surround the bacterial DNA

What term is used to describe a bacterial cell that is slightly "bend rod" shape; also called comma-shaped?

Vibrio

Most all spirochete- or corkscrew-motility bacteria have their flagella ___.

Within the periplasmic space

When conditions become hostile, some bacteria can produce ___ which allows them to survive until conditions become more moderate.

an endospore

The bacterial shape known as a rod is also termed: ___.

bacillus

Capsules are typically ___.

composed of sugars

Bacterial cell can only acquire nutrients that are ___.

dissolved

As you add more and more solutes, facilitated diffusion will ___.

eventually only diffuse a set amount of solutes per minute

This graph indicates that facilitate diffusion initially operates ___ than passive diffusion.

faster

Relative to the cell, the bacterial ___ is a long tube structure that can spin resulting in cell motility.

flagella

The role of teichoic acids appear to be to ___.

give added strength to the cell wall

Lipids in membranes arrange ___.

heads toward the water side

Lipids arranged in a bilayer will have the outside of the membrane be ___.

hydrophilic

Iron is generally difficult for microbes to acquire because ___.

it is insoluble

Chlamydiae organisms are unlike other gram-negative bacteria in that they ___.

lack peptidoglycan

Endospores have ___ membranes surrounding the core.

more than one

Chemotaxis is a process by which bacteria ___.

move toward an attractant or away from a repellent.

Lipids in the membranes arrange ___.

tail to tail (hydrophobic tail to hydrophobic tail)

Historically, prokaryotes were differentiated from eukaryotes by ___.

the absence of a nucleus

The amphipathic character of lipids found in plasma membranes implies ___.

the lipid is asymmetric

Active transport and facilitated diffusion are difference because active transport ___.

uses ATP to power the movement of materials across a membrane


Ensembles d'études connexes

Lección 8: Estructura: 8.2, 8.3, y 8.4

View Set

Habermas, "Truth and Society: The Discursive Redemption..." (critical)

View Set

Unit Three: More Proofs - Transversals and Special Angles

View Set

MAR3231 Hopkins Exam 2 Study Questions

View Set

Chapter 18 The Gram-Positive and Gram-Negative Cocci of Medical Importance

View Set

Mood Disorders Practice Questions (Test #3, Fall 2020)

View Set