BIO 175 Exam 1 Study Guide Questions and
Answers Verified by Experts
How is the flagellum anchored to the bacterium? The filament is attached to the hook
Amphitrichous flagella at both poles of the cell
Pertrichous flagella from all surfaces of cell
Lophotrichous small bunches or tufts of flagella emerging from the same site
Monotrichous single flagellum
Atrichous bacteria that lack flagella
What is taxis? movement towards or away from a stimulus.
Chemotaxis Cell movement that occurs in response to chemical stimulus.
,positive chemotaxis movement toward favorable chemical stimulus
negative chemotaxis movement away from a repellant
Phototaxis movement toward or away from light
Positive phototaxis movement towards light
Negative phototaxis movement away from light
Why would someone use a gram stain? To determine whether a bacterial infection is
present or non existing
What part of bacterium is stained by a gram stain? peptidoglycan
How do you identify a gram-positive stain? The bacteria will turn purple
, How do you identify a gram-negative stain? The bacteria will turn pink or red
What is peptidoglycan? a polymer consisting of sugars and amino acids that forms a
mesh-like layer outside the plasma membrane of bacteria (but not Archaea)
Where is peptidoglycan found? cell wall
How does acid-fact bacteria differ from gram-positive and gram-negative bacteria? The
Acid-Fast cell wall consists of a thick, outer lipid-rich layer composed primarily of the fatty acid
"Mycolic Acid".
What are lysozymes? enzymes that kill bacteria
Where are lysozymes found? Tears, saliva, nasal and sinus fluids
What type of bacteria are lysozymes most effective against? gram-positive bacteria
Describe the DNA in bacteria Lack of nucleus and histones
Answers Verified by Experts
How is the flagellum anchored to the bacterium? The filament is attached to the hook
Amphitrichous flagella at both poles of the cell
Pertrichous flagella from all surfaces of cell
Lophotrichous small bunches or tufts of flagella emerging from the same site
Monotrichous single flagellum
Atrichous bacteria that lack flagella
What is taxis? movement towards or away from a stimulus.
Chemotaxis Cell movement that occurs in response to chemical stimulus.
,positive chemotaxis movement toward favorable chemical stimulus
negative chemotaxis movement away from a repellant
Phototaxis movement toward or away from light
Positive phototaxis movement towards light
Negative phototaxis movement away from light
Why would someone use a gram stain? To determine whether a bacterial infection is
present or non existing
What part of bacterium is stained by a gram stain? peptidoglycan
How do you identify a gram-positive stain? The bacteria will turn purple
, How do you identify a gram-negative stain? The bacteria will turn pink or red
What is peptidoglycan? a polymer consisting of sugars and amino acids that forms a
mesh-like layer outside the plasma membrane of bacteria (but not Archaea)
Where is peptidoglycan found? cell wall
How does acid-fact bacteria differ from gram-positive and gram-negative bacteria? The
Acid-Fast cell wall consists of a thick, outer lipid-rich layer composed primarily of the fatty acid
"Mycolic Acid".
What are lysozymes? enzymes that kill bacteria
Where are lysozymes found? Tears, saliva, nasal and sinus fluids
What type of bacteria are lysozymes most effective against? gram-positive bacteria
Describe the DNA in bacteria Lack of nucleus and histones
