CH4: Prokaryotic & Eukaryotic Cells

Which of the following scenarios is an example of bacterial motility? A. A bacterium moving towards a food source B. A bacterium traveling through the air from a sneeze C. A bacterium being removed from the skin during hand washing

A bacterium moving towards a food source

Indicate the bacterial structures that are likely to be antigens, to which host antibodies bind, marking the invader for phagocytosis (more than one). A. fimbriae B. ribosomes C. cell wall D. apsule E. nucleoid F. flagella G. plasmids

A. fimbriae C. cell wall D. capsule F. flagella

Identify antibacterial strategies that would likely be selectively toxic for bacteria (more than one). A. inhibition of peptidoglycan synthesis B. inhibition of microtubule function C. inhibition of fimbriae synthesis D. interfering with lysosomal function E. interfering with translation at 70s ribosomes

A. inhibition of peptidoglycan synthesis C. inhibition of fimbriae synthesis E. interfering with translation at 70s ribosomes

Which of the following statements about ribosomes is FALSE? A. Cells with a high rate of protein synthesis have large numbers of ribosomes. B. All eukaryotic and prokaryotic cells contain ribosomes. C. Antibiotics that interfere with protein synthesis harm both prokaryotic and eukaryotic ribosomes. D. Eukaryotic ribosomes are larger (80S) than prokaryotic ribosomes (70S).

Antibiotics that interfere with protein synthesis harm both prokaryotic and eukaryotic ribosomes.

Which of the following is true of bacteria that have atypical cell walls, such as those in the genus Mycoplasma? A. These atypical bacteria usually stain gram-negative. B. Although small, these atypical bacteria cannot pass through most filters. C. Bacteria with atypical cell walls are generally among the smallest bacteria that can reproduce outside a host cell. D. These atypical bacteria have the same plasma membrane typical of bacteria.

Bacteria with atypical cell walls are generally among the smallest bacteria that can reproduce outside a host cell.

Which of the following statements is true? A. One bacterial cell produces many endospores. B. Endospores allow a cell to attach to solid surfaces and to surfaces within the host. C. Endospores are extremely durable structures that can survive high temperatures. D. Endospores are reproductive structures.

Endospores are extremely durable structures that can survive high temperatures.

There are some structures that are common to all prokaryotic cells, and others that are only found in some bacterial species or strains. Select the structures below that are found in all bacterial cells. (more than one) A. cell wall B. flagella C. capsule D. pilus (pili) E. fimbriae F. ribosomes G. plasma membrane H. cytoplasm I. nucleoid

F. ribosomes G. plasma membrane H. cytoplasm I. nucleoid

Acid-fast bacteria demonstrate unique staining properties because of a special protein layer found in their cell walls.

False

Bacteria do not have chloroplasts and therefore cannot perform photosynthesis.

False

Penicillin is more effective against gram-negative bacteria than gram-positive bacteria because it specifically interferes with the synthesis of lipopolysaccharide.

False

The cell walls of bacteria and eukaryotes are very similar.

False

True/ False Cells placed in a hypotonic solution tend to lose water due to osmotic pressure.

False

What is the advantage to spirochetes of the corkscrew movement provided by axial filaments? A. It makes spirochete cells more flexible, and prevents them from breaking as easily as bacillus-shaped bacteria. B. It hides the flagella, so they are not as easily detected by the immune system. C. It provides faster movement, allowing the spirochete to escape the cells of the immune system. D. It allows the cells to move more easily through viscous human tissues and fluids, such as mucus.

It allows the cells to move more easily through viscous human tissues and fluids, such as mucus.

All of the following are true of the gram-negative outer membrane except: A. It has polysaccharide antigens that are useful in bacterial identification. B. It contains lipopolysaccharide. C. It contains lipids also known as endotoxin. D. It contains enzymes for energy synthesis. E. It is a part of the gram-negative cell wall

It contains enzymes for energy synthesis.

Which of the following statements about a gram-negative cell wall is FALSE? A. It contains teichoic acid. B. It maintains the shape of the cell. C. It functions as an endotoxin. D. It includes a thin layer of peptidoglycan.

It contains teichoic acid.

Which of the following is a likely outcome, based on the unique cell structure of members of the genus Mycoplasma? A. Mycoplasma species are susceptible to disruption by lysozymes. B. Mycoplasma species can release endotoxins when they lyse. C. Mycoplasma species have very flexible cells that can pass through bacteriologic filters. D. Mycoplasma species are susceptible to penicillin. E. Mycoplasma species usually stain gram-positive.

Mycoplasma species have very flexible cells that can pass through bacteriologic filters.

Which statement best describes what happens when a gram-positive bacterium is placed in an aqueous solution of lysozyme and 10% sucrose? A. No change will result; the solution is isotonic B. Water will move into the cell C. Water will move out of the cell D. The cell will undergo osmotic lysis E. Sucrose will move into the cell from an area of higher concentration to one of lower concentration

No change will result; the solution is isotonic

Which of the following is a difference between gram-positive and gram-negative cells? A. Only gram-negative cells have a lipopolysaccharide (LPS) layer. B. Only gram-positive cells have peptidoglycan that is made of a carbohydrate backbone. C. Gram-negative cell walls contain teichoic acids. D. Gram-positive cells contain less peptidoglycan than do gram-negative cells.

Only gram-negative cells have a lipopolysaccharide (LPS) layer.

Why is penicillin selectively toxic to bacterial cells but harmless to human cells? A. The glycocalyx of an animal cell provides a barrier through which penicillin cannot pass. B. Penicillin is rapidly metabolized and destroyed by human cells. C. Human cells actively transport penicillin out of the cell. D. Penicillin is inactivated within lysosomes of human cells. E. Penicillin specifically weakens peptidoglycan, which is found only in bacterial cells.

Penicillin specifically weakens peptidoglycan, which is found only in bacterial cells.

Which of the following statements is false? A. Plant cells have a cell wall, while animal cells do not have a cell wall. B. Plant cells do not have mitochondria. C. Both plant and animal cells have nuclei, which house just about all of the eukaryotic cell's DNA. D. Plant cells contain the organelles to carry out photosynthesis.

Plant cells do not have mitochondria.

Which of the following statements does NOT provide evidence for the endosymbiotic theory? A. The ribosomes contained within mitochondria and chloroplasts are very similar to prokaryotic ribosomes. B. Prokaryotes contain peptidoglycan in their cell walls. C. The same antibiotics that inhibit protein synthesis in prokaryotes also inhibit protein synthesis within mitochondria and chloroplasts. D. Mitochondria and chloroplasts contain circular DNA, similar to the DNA in prokaryotes.

Prokaryotes contain peptidoglycan in their cell walls.

How do axial filaments differ from regular bacterial flagella? A. They do not rotate. B. They do not function in cell movement. C. The axial filament is located between the cell membrane and the outer membrane.

The axial filament is located between the cell membrane and the outer membrane.

Which statement best describes what happens when a gram-positive bacterium is placed in distilled water and penicillin? A. No change will result; the solution is isotonic B. Water will move into the cell C. Water will move out of the cell D. The cell will undergo osmotic lysis E. Sucrose will move into the cell from an area of higher concentration to one of lower concentration

The cell will undergo osmotic lysis

What statement most accurately describes the structure of the plasma membrane? A. Peripheral proteins span the membrane. B. The plasma membrane is a phospholipid bilayer with the hydrophilic phosphate groups oriented toward the inside and outside of the cell. C. The lipid portion of the bilayer is hydrophilic. D. The plasma membrane is a phospholipid bilayer with the hydrophilic phosphate groups oriented toward one another.

The plasma membrane is a phospholipid bilayer with the hydrophilic phosphate groups oriented toward the inside and outside of the cell

The nucleus of a eukaryotic cell differs from the nucleoid of a prokaryotic cell in all of the following ways EXCEPT which one? A. The prokaryotic nucleoid usually contains a single circular chromosome, whereas the eukaryotic nucleus contains multiple linear chromosomes. B. The eukaryotic nucleus is surrounded by a nuclear envelope. There is no envelope surrounding the prokaryotic nucleoid. C. The prokaryotic nucleoid contains DNA combined with histones. Histones are lacking in the eukaryotic nucleus. D. The eukaryotic nucleus contains nucleoli. There are no nucleoli in the prokaryotic nucleoid.

The prokaryotic nucleoid contains DNA combined with histones. Histones are lacking in the eukaryotic nucleus.

Why are receptors on the cell surface necessary for bacterial movement? A. The bacterium contains receptors that are sensitive to light. B. The receptors actually spin the flagella. C. The receptors sense the stimulus and send signals to the flagella. D. The receptors physically alter shape to steer the bacterium.

The receptors sense the stimulus and send signals to the flagella.

Which of the following is not a distinguishing characteristic of prokaryotic cells? A. They usually have a single, circular chromosome. B. They lack membrane-enclosed organelles C. They have cell walls containing peptidoglycan D. Their DNA is not associated with histones E. They lack a plasma membrane

They lack a plasma membrane

Which of the following statements is INCORRECT regarding prokaryotic cells? A. They reproduce by binary fission. B. They typically have a circular chromosome. C. Their DNA is not enclosed within a membrane. D. They lack a plasma membrane. E. They lack membrane-enclosed organelles

They lack a plasma membrane.

Which of the following is false about fimbriae? A. They are composed of protein B. They maybe used for attachment C. They are found on gram-negative cells D. They are composed of pilin E. They may be used for motility

They may be used for motility

Endospores can remain dormant for thousands of years. Once this dormant structure is provided appropriate nutrients and growth conditions, it will germinate to form a viable bacterial cell.

True

The cell membrane is a fluid structure that allows membrane proteins to move freely.

True

The following bacterial structures increase the likelihood that bacteria will be associated with disease: capsules, fimbriae, and LPS.

True

The plane in which a bacterial cell divides determines the arrangement of cells.

True

True/ False Spheroplasts, protoplasts, and mycoplasms are bacterial cells without cell walls.

True

Which statement best describes what happens when a gram-negative bacterium is placed in distilled water and penicillin? A. No change will result; the solution is isotonic B. Water will move into the cell C. Water will move out of the cell D. The cell will undergo osmotic lysis E. Sucrose will move into the cell from an area of higher concentration to one of lower concentration

Water will move into the cell

You have isolated a cell with a peptidoglycan cell wall. What other structure can you safely assume the cell has? A. a mitochondrion B. a chloroplast C. a nucleus D. a plasma membrane

a plasma membrane

During endospore formation, ________. A. the only DNA that is copied contains the genes necessary for germination B. the cell is experiencing a great deal of metabolic activity C. a thick spore coat forms around the forespore before the endospore is released into the environment D. the population of bacterial cells doubles

a thick spore coat forms around the forespore before the endospore is released into the environment

Which of the following eukaryotic cells do NOT contain a cell wall? A. animals B. plants C. algae D. fungi

animals

Bacillus anthracis causes the deadly disease anthrax. Organisms of the genus Bacillus may form endospores. This bacterium would be suitable for biological warfare because endospores ________. A. have a high concentration of calcium ions B. are difficult to stain C. are centrally located within the bacterial cells D. are multilayered structures E. are resistant to high temperatures, UV light, and desiccation

are resistant to high temperatures, UV light, and desiccation

Functions of the glycocalyx include all of the following EXCEPT A. biofilm formation. B. source of nutrition. C. binary fission. D. increased virulence. E. protection against dehydration.

binary fission.

Many pathogenic (disease-producing) bacteria have _______ that protect them from phagocytosis by host cells.

capsules

Compared to other bacteria, mycoplasmas are somewhat atypical because they do not have a _______.

cell wall

Which of the following is not a structure of prokaryotic cells? A. chromosome B. chloroplast C. capsule D. ribosome E. flagella

chloroplast

Which of the following structures is NOT found in some prokaryotic cells? A. peritrichous flagella B. cilium C. pilus D. axial filament E. flagellum

cilium

Short, prokaryotic appendages made up of pilin are called pili. Special pili involved in the transfer of DNA from one cell to another are called ______.

conjugation pili

The nuclear area of the bacterial cell ________. A. has abundant histone proteins B. is connected to the endoplasmic reticulum C. contains many linear chromosomes D. is enclosed in a nuclear membrane E. contains the bacterial chromosome

contains the bacterial chromosome

Which of the following is NOT characteristic of the glycocalyx found in bacteria? A. creates a slimy, slippery coating that prevents bacteria form attaching to surfaces B. if firmly attached, contributes to bacterial virulence C. a structure that can be visualized by negative staining D. a viscous coating surrounding the cell made of polysaccharide, polypeptide, or both

creates a slimy, slippery coating that prevents bacteria form attaching to surfaces

Spirochetes and spirilla are both spiral-shaped bacteria. However, they differ in that spirochetes have __________ and spirilla do not. A. fimbriae B. endoflagella (axial filaments) C. N-acetylglucosamine D. peritrichous flagella

endoflagella (axial filaments)

When essential nutrients are depleted, some strains of bacteria form ______, dormant structures that form within cells.

endospores

Sequence the path of a solute from the external environment to the cytoplasm of a prokaryotic cell.

external environment --> capsule --> cell wall --> plasma membrane --> cytoplasm

Which of the following processes uses membrane proteins that act as channels or carriers allowing ions or large molecules to move across the plasma membrane without using energy? A. active transport B. simple diffusion C. facilitated diffusion D. osmosis

facilitated diffusion

Which of the following bacterial structures is necessary for chemotaxis? A. flagella B. plasmids C. metachromatic granules D. capsules

flagella

The antibiotic amphothericin B disrupts plasma membranes by combining with sterols; it will affect all of the following cells except A. animal cells B. gram-negative bacterial cells C. fungal cells D. Mycoplasma cells E. plant cells

gram-negative bacterial cells

Which cell wall is resistant to many antibiotics (e.g., penicillin)? A. gram-positive cell wall B. gram-negative cell wall C. both a and b D. neither a nor b E. The answer cannot be determined.

gram-negative cell wall

which a cell wall contains porins? A. gram-positive cell wall B. gram-negative cell wall C. both a and b D. neither a nor b E. The answer cannot be determined.

gram-negative cell wall

which diagram of a cell wall is decolorized by alcohol? A. gram-positive cell wall B. gram-negative cell wall C. both a and b D. neither a nor b E. The answer cannot be determined.

gram-negative cell wall

Penicillin specifically interferes with peptidoglycan synthesis. Which of the following cells is most likely to be damaged by penicillin? A. human cells B. yeast cells C. cells of archaea D. gram-positive bacterial cells

gram-positive bacterial cells

A Gram stain of a wound reveals purple, spherical-shaped bacteria that divide and remain attached in grapelike clusters. These are referred to as __________. A. gram-positive staphylococci B. gram-positive tetrads C. gram-positive streptococci D. gram-negative spirochetes

gram-positive staphylococci

You are observing a Gram stain of rectangular-shaped microorganisms that are linked in a chain and stain purple. How would you describe these bacteria using the correct terminology for the cell shape and arrangement? A. gram-positive coccobacilli B. gram-positive streptobacilli C. gram-positive tetrads D. gram-negative staphylococci

gram-positive streptobacilli

Polyphosphate (volutin), carboxysomes, and magnetosomes are examples of ________. A. mesosomes B. fimbriae C. inclusion bodies D. chloroplasts E. capsules

inclusion bodies

Within the cytoplasm of bacterial cells are reserve deposits where certain nutrients accumulate. These are called __________. A. vacuoles B. inclusions C. ribosomes D. lysosomes

inclusions

The plasma membrane is considered a barrier to the environment because ________. A. only water and small molecules may penetrate the membrane B. the membrane is the outermost structure of the cell C. it controls the passage of molecules into the cell D. it is a rigid structure E. no molecules may pass through it

it controls the passage of molecules into the cell

All of the following are found in the cell walls of gram-positive bacteria except ________. A. lipid A B. teichoic acid C. peptidoglycan D. N-acetylglucosamine E. lipoteichoic acid

lipid A

Which of the following organelles breaks down worn-out organelles? A. rough endoplasmic reticulum (ER) B. lysosomes C. smooth endoplasmic reticulum (ER) D. mitochondria E. Golgi apparatus

lysosomes

Chemotaxis refers to the ability of microorganisms to ________. A. move in a wavelike motion B. escape phagocytosis C. move toward or away from chemical stimuli D. attach to solid surfaces E. survive under adverse conditions

move toward or away from chemical stimuli

In a prokaryotic cell, all of the following are functions of either the fimbriae or pili EXCEPT __________. A. transfer of DNA B. movement C. formation of biofilms D. attachment to a surface

movement

Taxis is A. another word for stimulus. B. movement towards or away from a stimulus. C. caused by the undulating motion of a bacterium. D. another term for bacterial tumbling.

movement towards or away from a stimulus.

Condensed regions of chromosomes in eukaryotes where rRNA is synthesized are called ______ .

nucleoli

Antibiotics that target cell wall synthesis ultimately cause bacterial cell death as a result of A. osmotic lysis. B. cell shrinkage. C. inhibition of molecular transport. D. decreased synthesis of peptidoglycan. E. plasmolysis.

osmotic lysis.

The term describing bacteria with flagella distributed over the entire surface of the cell is _____ .

peritrichous

A eukaryotic cell can ingest a prokaryotic cell by ________. A. digestive vacuolization B. active transport C. pinocytosis D. phagocytosis E. osmosis

phagocytosis

Which of the following pairs is mismatched? A. glycocalyx - adherence B. pili - reproduction C. cell wall - toxin D. cell wall - protection E. plasma membrane - transport

pili - reproduction

Which of the following is not a functionally analogous pair? A. circular bacterial chromosome; -linear eukaryotic chromosomes B. pili; centrioles C. peptidoglycan; cellulose D. bacterial flagella; 9 + 2 flagella E. 70S ribosomes; 80S ribosomes

pili; centrioles

What structure acts as a selective barrier, regulating the traffic of materials into and out of the cell? A. cytoskeleton B. nuclear envelope C. extracellular matrix D. endomembrane system E. plasma membrane

plasma membrane

Where are phospholipids most likely found in a prokaryotic cell? A. flagella B. around organelles C. plasma membrane D. ribosomes E. plasma membrane and around organelles

plasma membrane

In a hypertonic solution, a bacterial cell will typically A. osmolyze. B. stay the same. C. plasmolyze. D. lyse. E. burst.

plasmolyze.

In a phospholipid bilayer, water interacts with the ______ of the phospholipid molecules.

polar heads, hydrophilic heads

Each of the following statements concerning the gram-positive cell wall is true EXCEPT it A. maintains the shape of the cell. B. contains teichoic acids. C. is sensitive to penicillin. D. is sensitive to lysozyme. E. protects the cell in a hypertonic environment.

protects the cell in a hypertonic environment.

You have isolated a motile, gram-positive cell with no visible nucleus. You can assume this cell has A. ribosomes B. mitochondria C. an endoplasmic reticulum D. a Golgi complex E. all of the above

ribosomes

Which of the following pairs is mismatched? A. metachromatic granules - stored phosphates B. polysaccharide granules - stored starch C. lipid inclusions - poly - b - hydroxybutyric acid D. sulfur granules - energy reserve E. ribosomes - protein storage

ribosomes - protein storage

Which one of the following pairs is mismatched? A. ribosomes - protein storage B. sulfur granules - energy reserve C. lipid inclusions - energy reserve D. gas vacuoles - flotation E. metachromatic granules - phosphate storage

ribosomes - protein storage

Which of the following pairs is mismatched? A. lysosome; digestive enzymes B. ribosomes; storage C. Golgi complex; secretion D. mitochondria; ATP production E. endoplasmic reticulum; internal transport

ribosomes; storage

Gram-negative cells contain a periplasmic space that is ________. A. filled with lysozyme B. a site of endocytosis C. rich in degradative enzymes D. abundant in photosynthetic pigments E. the site of protein synthesis

rich in degradative enzymes

As a bacterium approaches a food source, one would expect A. flagella to stop spinning. B. tumbles to become more frequent. C. flagella to rotate clockwise more frequently. D. runs to become more frequent.

runs to become more frequent.

Consider a gram-positive cell in a hypertonic medium. If the peptidoglycan were damaged, the cell would _____.

shrink, plasmolyze, collapse

Which of the following is matched correctly? A. protoplast--a genus of bacteria that typically do not have cell walls B.spheroplast--gram-negative bacteria that are exposed to lysozyme but retain some of the outer membrane C. Mycoplasma spp.--bacteria that spontaneously, or in response to penicillin or lysozyme, partially lose their cell walls and swell into irregularly shaped bacteria that divide and metabolize and may regain their cell wall D. L form--a wall-less bacterium created by the action of lysozyme; the plasma membrane remains intact, and the cell carries on metabolism.

spheroplast--gram-negative bacteria that are exposed to lysozyme but retain some of the outer membrane

Axial filaments are found on A. streptococci. B. spirochetes. C. rod-shaped bacilli. D. staphylococci.

spirochetes.

Assume you are growing a bacterial culture in a glucose medium. Your lab partner adds more glucose in hopes of speeding up the experiment. The bacteria suddenly die. The best explanation for this result is that ________. A. the bacteria could not use glucose B. the cells plasmolyzed C. osmotic lysis occurred D. glucose is toxic to bacteria E. the cells underwent sporulation

the cells plasmolyzed

Tumbles occur when A. the flagella rotate counterclockwise. B. the flagella undulate. C. the flagella rotate clockwise. D. the flagella stop rotating

the flagella rotate clockwise.

The motility of bacteria with flagella occurs through a series of "runs" and _____.

tumbles