Microbiology 2516

2- is a type of peripheral protein above that can be used as a receptor or in enzymatic functions.

A glycoprotein 1- can be used in enzymatic functions. 2- is a type of peripheral protein above that can be used as a receptor or in enzymatic functions. 3- is a type of peripheral protein. 4- can be used as a receptor.

2- purple, spherical-shaped organisms arranged in chainlike formations

Analysis of the second swab has confirmed that the causative organism is Streptococcus pyogenes, a gram-positive organism. Imagine that you are the technician looking at the Gram stain from Shelly's culture. What would you expect to see as you look through the microscope? 1-pink, spherical-shaped organisms arranged in chainlike formations 2- purple, spherical-shaped organisms arranged in chainlike formations 3- pink, rod-shaped organisms arranged in pairs 4- purple, spherical-shaped organisms arranged in grapelike clusters

4-runs to become more frequent.

As a bacterium approaches a food source, one would expect 1 tumbles to become more frequent. 2 flagella to stop spinning. 3 flagella to rotate clockwise more frequently. 4 runs to become more frequent.

2-endoflagella.

Axial filaments are composed of 1 the outer membrane. 2 endoflagella. 3 axial fibers.

3- it protects the cell in a hypertonic environment.

Each of the following statements concerning the gram-positive cell wall is true EXCEPT 1- it contains teichoic acids. 2-it maintains the shape of the cell. 3- it protects the cell in a hypertonic environment. 4- it is sensitive to lysozyme. 5- it is sensitive to penicillin.

4) binary fission

Functions of the glycocalyx include all of the following EXCEPT 1) biofilm formation. 2)increased virulence. 3)protection against dehydration. 4) binary fission. 5) source of nutrition

The glycocalyx is a glycoprotein-polysaccharide covering that surrounds the cell membranes of some bacteria, epithelia and other cells. Most animal epithelial cells have a fuzz-like coat on the external surface of their plasma membranes. This coating consists of several carbohydrate moieties of membrane glycolipids and glycoproteins, which serve as backbone molecules for support. Generally, the carbohydrate portion of the glycolipids found on the surface of plasma membranes helps these molecules contribute to cell-cell recognition, communication, and intercellular adhesion. The glycocalyx is a type of identifier that the body uses to distinguish between its own healthy cells and transplanted tissues, diseased cells, or invading organisms. Included in the glycocalyx are cell-adhesion molecules that enable cells to adhere to each other and guide the movement of cells during embryonic development. The glycocalyx plays a major role in regulation of endothelial vascular tissue, including the modulation of red blood cell volume in capillaries. The slime on the outside of a fish is an example of glycocalyx. The term was initially applied to the polysaccharide matrix coating epithelial cells, but its functions have been discovered to go well beyond that.

Glycocalyx what is it?

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

How do axial filaments differ from regular bacterial flagella? 1 They do not rotate. 2 They do not function in cell movement. 3 The axial filament is located between the cell membrane and the outer membrane.

3) Spirilla have an external flagella but spirochetes have axial filaments.

How do spirochetes and spirilla differ? 1) Spirilla are found in chains of cells whereas spirochetes exist as individual cells. 2) Spirochetes and spirilla are basically the same organisms and the terms can be used interchangeably. 3) Spirilla have an external flagella but spirochetes have axial filaments. 4)Spirochetes do not have a cell wall but spirilla do. 5)Spirochetes have a rigid, corkscrew shape while spirilla are helical and more flexible

1- By simple diffusion or by use of an integral transport protein

How does water enter and exit a cell? 1- By simple diffusion or by use of an integral transport protein 2- By use of a peripheral transport protein 3- By simple diffusion across the membrane 4- By use of an integral transport protein

1-Water movement is driven by the concentration of solutes rather than its own concentration.

How is osmosis different from simple diffusion? 1-Water movement is driven by the concentration of solutes rather than its own concentration. 2-Water cannot pass freely across the membrane. 3- Water requires a special permease. 4-Water requires energy to move across a cytoplasmic membrane.

3- Simple diffusion does not require a permease.

How is simple diffusion different from other types of passive transport? 1- Simple diffusion requires ATP. 2-Simple diffusion only brings material into the cell, not out of it. 3- Simple diffusion does not require a permease. 4-Simple diffusion is only the diffusion of water.

2- Penicillin will interfere with peptidoglycan synthesis, ultimately weakening the cell wall and leading to cellular lysis.

How will the prescribed penicillin kill S. pyogenes that is causing Shelly's infection? 1-Penicillin will attach to bacterial ribosomes and inhibit protein synthesis, which will lead to the death of S. pyogenes. 2- Penicillin will interfere with peptidoglycan synthesis, ultimately weakening the cell wall and leading to cellular lysis. 3- Penicillin will disrupt the outer membrane, leading to a loss of structural integrity and death of S. pyogenes. 4- Penicillin will poke holes in the plasma membrane, weakening the cell and leading to cellular lysis.

.plasmolyze

In a hypertonic solution, a bacterial cell will typically 1 stay the same. 2 lyse. 3 plasmolyze. 4 burst. 5 osmolyze

2-B (GRAM NEGATIVE)

In the figure, which diagram of a cell wall contains porins? 1 a 2 b 3 both a and b 4 neither a nor b 5 The answer cannot be determined based on the information provided.

1- a (gram positive cell wall)

In the figure, which diagram of a cell wall contains teichoic acids? 1- a 2- b 3- both a and b 4- neither a nor b 5- The answer cannot be determined based on the information provided.

3-both a and b

In the figure, which diagram of a cell wall has a structure that protects against osmotic lysis?(pic in next) 1-a 2-b 3-both a and b 4-neither a nor b 5-The answer cannot be determined based on the information provided.

2-b

In the figure, which diagram of a cell wall is a gram-negative cell wall? (picture in next side) 1- a 2- b 3- both a and b 4- neither a nor b 5- The answer cannot be determined based on the information provided.

2- b(gram negative)

In the figure, which diagram of a cell wall is decolorized by alcohol?(pic in next) 1- a 2- b 3- both a and b 4- neither a nor b 5- The answer cannot be determined based on the information provided.

2- b (gram negative cell wall)

In the figure, which diagram of a cell wall is resistant to many antibiotics (e.g., penicillin)? 1- a 2- b 3- both a and b 4- neither a nor b 5- The answer cannot be determined based on the information provided.

2-b (gram negative)

In the figure, which diagram of a cell wall possesses lipid A/endotoxin responsible for symptoms associated with infection?(picture in next) 1- a 2- b 3- both a and b 4- neither a nor b 5- The answer cannot be determined based on the information provided.

3- transport function

Integral proteins are mostly involved in 1- enzymatic function. 2- recognition sites. 3- transport function. 4- receptors.

4- allow a variety of molecules to cross the cytoplasmic membrane.

Nonspecific permeates 1- are not used for passive transport. 2- allow only water to cross the cytoplasmic membrane. 3- allow only one type of solute to pass through the membrane. 4- allow a variety of molecules to cross the cytoplasmic membrane.

Fluid Mosaic Model of Membrane Structure

Phospholipid bilayer in which proteins float

4) the flagella turn counterclockwise and become bundled

Peritrichous bacteria make a run when 1) the flagella turn counterclockwise and separate. 2) the flagella turn clockwise and become bundled. 3) the flagella turn clockwise and separate. 4) the flagella turn counterclockwise and become bundled.

2)movement towards or away from a stimulus.

Taxis is 1)another term for bacterial tumbling. 2)movement towards or away from a stimulus. 3)caused by the undulating motion of a bacterium. 4)another word for stimulus.

4- is circular in structure.

The DNA found in most bacterial cells 1- is linear in structure. 2- is surrounded by a nuclear membrane. 3- is found in multiple copies. 4- is circular in structure. 5- utilizes histones for chromosomal packaging.

True

The cell walls of bacteria are responsible for the shape of the bacteria and the difference in the Gram stain reaction. True OR False

1- requires transporter proteins.

The difference between simple diffusion and facilitated diffusion is that facilitated diffusion 1- requires transporter proteins. 2- does not require ATP. 3- moves materials from a lower to a higher concentration. 4- moves materials from a higher to a lower concentration. requires ATP.

true

True or false. The cell walls of bacteria are responsible for the shape of the bacteria and the difference in the Gram stain reaction.

4- contains cholesterol

Which of the following is NOT a typical characteristic of most bacterial plasma membranes? 1-site of energy production 2- is selectively permeable 3- contains proteins 4- contains cholesterol 5- composed of a phospholipid bilayer

3) the flagella rotate clockwise

Tumbles occur when 1) the flagella stop rotating. 2) the flagella undulate. 3) the flagella rotate clockwise. 4) the flagella rotate counterclockwise.

1- The penicillin will not have any impact on Shelly's cells because it targets peptidoglycan, which is found only in bacteria.

What effect will the penicillin have on Shelly's cells? 1- The penicillin will not have any impact on Shelly's cells because it targets peptidoglycan, which is found only in bacteria. 2-The penicillin will also kill some of Shelly's cells by disrupting the structure of the plasma membrane. 3- There will be no impact on Shelly's cells because penicillin targets the flagella, which are found only in bacteria. 4- The penicillin will kill some of Shelly's cells because it targets the ribosomes, a structure found in both prokaryotes and eukaryotes.

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

What is the advantage to spirochetes of the corkscrew movement provided by axial filaments? 1 It provides faster movement, allowing the spirochete to escape the cells of the immune system. 2 It hides the flagella, so they are not as easily detected by the immune system. 3 It allows the cells to move more easily through viscous human tissues and fluids, such as mucus. 4 It makes spirochete cells more flexible, and prevents them from breaking as easily as bacillus-shaped bacteria.

2- They have both hydrophilic and hydrophobic regions.

What makes phospholipid membranes good at keeping some molecules out, and allowing others to freely pass? 1- They are positively charged. 2- They have both hydrophilic and hydrophobic regions. 3- They are completely hydrophobic. 4- They are completely hydrophilic.

2-The cell will lose its interior water, causing it to shrivel up and possibly die.

What will happen to a cell that is placed in a solution containing a high concentration of sugar, a molecule that cannot pass across the cell membrane? 1-The cell will pump the salt in the cytoplasm out of the cell via simple diffusion. 2-The cell will lose its interior water, causing it to shrivel up and possibly die. 3-The cell will swell up with water and burst.

4 the plasma membrane

Where are phospholipids most likely found in a prokaryotic cell? 1 around organelles 2 ribosomes 3 the plasma membrane and around organelles 4 the plasma membrane 5 flagella

1- mitochondrion

Which of the following organelles most closely resembles a prokaryotic cell? 1- mitochondrion 2- nucleus 3- cell wall 4- Golgi complex 5- vacuole

3) Flagella can rotate 360 degrees.

Which of the following statements about bacterial flagella is true? 1) Bacteria can only rotate flagella counterclockwise. 2) Bacteria can only rotate flagella clockwise. 3) Flagella can rotate 360 degrees. 4) Flagella work by undulating.

4) They are sensitive to penicillin.

Which of the following statements about gram-negative cell walls is FALSE? 1) They are toxic to humans. 2) They have an extra outer layer composed of lipoproteins, lipopolysaccharides, and phospholipids. 3) They protect the cell in a hypotonic environment. 4)They are sensitive to penicillin. 5) Their Gram reaction is due to the outer membrane.

2- will move out of the cell.

Which of the following statements best describes what happens when a bacterial cell is placed in a solution containing 5% NaCl? 1 Water will move into the cell. 2 Water will move out of the cell. 3 The cell will undergo osmotic lysis. 4 Sucrose will move into the cell from a higher to a lower concentration. 5 No change will result; the solution is isotonic.

1-cilium

Which of the following structures is NOT found in some prokaryotic cells? 1-cilium 2- flagellum 3- peritrichous flagella 4- pilus 5- axial filament

3) Lophotrichous flagella

Which of the following terms best describes the cell in the figure?(IMAGE WITH ANSWER) monotrichous flagellum 1) axial filament 2) amphitrichous flagella 3) lophotrichous flagella 4)peritrichous flagella

2) Positive phototaxis

Which of the following terms refers to a bacterium moving towards a light source? 1 Positive chemotaxis 2 Positive phototaxis 3 Negative chemotaxis 4 Negative phototaxis

5) Lophotrichous and monotrichous

Which of the following types of bacterial cells would have flagella located at only one end of the cell? 1) Monotrichous and amphitrichous 2) Monotrichous 3) Amphitrichous 4) Lophotrikhous 5) Lophotrichous and monotrichous 6) Peritrichous

2)monotrichous

Which of the following types of bacterial cells would have only a single flagellum? 1) Peritrichous 2) Monotrichous 3) Lophotrikhous 4) Amphitrichous 5) Lophotrichous and

2- ribosomes - carbon storage

Which one of the following pairs is mismatched? 1-lipid inclusions - energy reserve 2- ribosomes - carbon storage 3- gas vacuoles - flotation 4- sulfur granules - energy reserve 5- metachromatic granules - phosphate storage

1- In eukaryotes, the ribosomes found in chloroplasts and mitochondria are 70S ribosomes, which are similar in size to prokaryotic ribosomes.

Which statement regarding the structure or function of ribosomes is correct? 1- In eukaryotes, the ribosomes found in chloroplasts and mitochondria are 70S ribosomes, which are similar in size to prokaryotic ribosomes. 2- Ribosomes are found both free-floating and attached to the rough endoplasmic reticulum in eukaryotes and in prokaryotes. 3- Ribosomes are the sites of lipid biosynthesis in both prokaryotes and eukaryotes. 4- The ribosomes in the prokaryote are slightly larger than those found in the eukaryotic endoplasmic reticulum.

2- Uniport and Symport

Which transport protein employs transporters that move molecules only in one direction? 1-Uniport, Antiport, and Symport 2- Uniport and Symport 3- Uniport 4- Antiport 5- Symport 6- Uniport and Antiport

3-Symport

Which type of active transport protein moves two molecules into the cell at the same time? 1- Uniport 2-Antiport 3-Symport 4-Antiport and Symport 5-Uniport, Symport, and Antiport

1- Antiport and Symport

Which type of active transport protein uses one protein to pump two different molecules? 1- Antiport and Symport 2- Uniport 3- Symport 4- Antiport 5- Uniport, Antiport, and Symport

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

Why are receptors on the cell surface necessary for bacterial movement? 1) The receptors actually spin the flagella. 2) The bacterium contains receptors that are sensitive to light. 3)The receptors physically alter shape to steer the bacterium. 4) The receptors sense the stimulus and send signals to the flagella.

1-ATP provides energy to transfer material against its concentration gradient.

Why is ATP necessary for active transport? 1-ATP provides energy to transfer material against its concentration gradient. 2-ATP is a constituent of the electrochemical gradient. 3-ATP is an important structural element of transport proteins. 4-ATP is in higher concentrations inside of the cell.

4)gram-positive streptococci

You are observing a Gram stain of spherical-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? 1)gram-positive coccobacilli 2)gram-positive tetrads 3)gram-negative staphylococci 4)gram-positive streptococci

5- has a cell wall.

You have isolated a motile, gram-positive cell with no visible nucleus. You can safely assume that the cell 1- has cilia. 2- has a mitochondrion. 3- has 9 pairs + 2 flagella. 4- lives in an extreme environment. 5- has a cell wall.