Biofilms & Endospores
Why do fungi grow spores?
a. They are used for reproduction of the fungus
b. They are needed for the fungus to be able to absorb nutrients
c. They are able to kill cells of the immune system
d. They help fungi to stick to body surfaces
a. They are used for reproduction of the fungus
What is one reason why the Gram stain is always done in clinical microbiology labs?
a. it will tell us whether or not the bacteria make fimbriae
b. Gram stains are the only way to if a microbe makes a biofilm
c. it is a first step in identifying which bacteria is causing an infection
d. Gram stains help us identify eukaryotic parasites
c. it is a first step in identifying which bacteria is causing an infection
Which of the following statements about yeasts is incorrect?
a. Dimorphic yeasts always live as a single yeast-form cell
b. True yeasts are not pathogens.
c. Yeasts are typically opportunistic pathogens
d. Yeasts are cells that are spherical or oval shaped
d. Yeasts are cells that are spherical or oval shaped
Which of the following stages is never an infective stage for helminth parasites?
2 correct answers
a. larva
b. adult
c. egg
d. cyst
b. adult or d. cyst
Which of the following is NOT a cell part or cell structure that all cells have in common?
2 answers
a. cytoplasm
b. nucleus
c. cell membrane
d. ribosome
b. nucleus or d. ribosome
Which of the following is an INCORRECT statement about endospores?
a. Endospores cannot be disinfected; they must be sterilized
b. Endospores are only released after the cell containing them dies
c. Endospores germinate when they find conditions favorable for cells to grow
d. Endospores are actively growing and dividing cells
d. Endospores are actively growing and dividing cells
Which of the following is NOT a function of a bacterial cell wall?
a. Protects some bacteria from being identified by the immune system
b. Provides shape and structural strength to the cell
c. Allows transfer of plasmids between cells
d. Helps bacteria stick to cells and surfaces
c. Allows transfer of plasmids between cells
30. What is one way that prokaryotic and eukaryotic chromosomes differ from each other?
a. Prokaryotes typically have one chromosome while eukaryotes have more than one.
b. Prokaryotic chromosomes are linear in shape but eukaryotic chromosmes are circular.
c. Prokaryotic chromosomes use histones but eukaryotic chromosomes do not.
d. Prokaryotic chromosomes are supercoiled but eukaryotic chromosomes are not.
a. Prokaryotes typically have one chromosome while eukaryotes have more than one.
Which of the following statements about toxoplasmosis is incorrect?
a. humans are the primary or definitive host for the Toxoplasma parasite
b. infections can be caused by consuming undercooked meat from animals with tissue cysts
c. toxoplasmosis is most severe in the immunosuppressed and infants
d. infections can be caused by exposure to fecal cysts in cat feces
a. humans are the primary or definitive host for the Toxoplasma parasite
What is an opportunistic pathogen?
a. a microbe that causes disease in more than one kind of organism
b. a microbe that spends part of its life in a dormant state
c. a microbe that can cause disease in an otherwise healthy organism
d. a microbe that can only cause disease in a weakened or compromised organism
d. a microbe that can only cause disease in a weakened or compromised organism
Though they share many similarities, endospores and fungal spores are different which important way?
a. Endospores are dormant but fungal spores are not
b. Fungal spores germinate but endospores are always actively growing and replicating
c. Endospores are much more resistant to disinfection and environmental change than fungal spores
d. Fungi always produce spores but endospores are only made when growth conditions are bad
c. Endospores are much more resistant to disinfection and environmental change than fungal spores
From the list below, choose the statement about the "external structures" of cells that is incorrect.
a. The external structures of prokarotic cells are very diverse in both type and function.
b. Bacterial cell walls are complex in structure and multifunctional
c. Most eukaryotic external structures are used for movement of cells
d. Nearly every kind of eukaryotic cell has a cell wall
d. Nearly every kind of eukaryotic cell has a cell wall
Of the following, which is on average the smallest?
a. eukaryotic cells
b. prokaryotic cells
c. viruses
c. viruses
For protozoan parasites, what life cycle stage is typically the infective stage?
a. larva
b. trophozoite
c. egg
d. cyst
d. cyst
What are the typical symptoms of uncomplicated malaria?
a. hypoglycemia
b. seizure and loss of consciousness
c. cyclical fever with severe chills
d. anemia
d. anemia
Which of the following accurately describes the structure of a mold?
a. The aerial hyphae of a mold are the part of the mold that absorb nutrients and anchor the mold
b. Molds are usually unicellular and round or oval shaped
c. Molds are often dimorphic and switch between a yeast and mold form
d. Molds are tangles of thin and thread-like cells that are large enough to see
d. Molds are tangles of thin and thread-like cells that are large enough to see
How does an acid-fast cell wall change the way that the immune system interacts with acid-fast bacteria?
a. The acid-fast cell wall does not change anything; the gram-positive cell wall does.
b. The immune system will cause a massive body-wide inflammatory reaction
c. The immune system will much more easily identify and kill the bacteria
d. The immune system will encase the bacteria inside a wall of tissue
d. The immune system will encase the bacteria inside a wall of tissue
Which eukaryotic organelle is responsible for breaking down and recycling old cell structures?
a. mitochondria
b. lysosome
c. peroxisome
d. Golgi apparatus
b. lysosome
How are some protozoan parasites endemic in colder/drier climates where they normally can't survive?
a. they make endospores that are resistant to most environmental conditions
b. they make cysts that are resistant to cold and dehydration
c. their eggs are much tougher than the adults and can survive cold temperatures
d. the spores they make are dormant and can survive in soil
b. they make cysts that are resistant to cold and dehydration
Which of the following is not a typical way that molds can cause human disease?
a. exposure to cysts causes a latent infection in the body for years
b. allergic reactions from exposure to the fungus or spores
c. infections where fungus grows in or on the body
d. production of toxins that make someone ill when consumed
b. allergic reactions from exposure to the fungus or spores
What is the purpose or function of an endospore for the bacteria that make them?
a. They allow the bacteria to hide out when growth conditions are bad
b. They allow bacteria to move into the next stage of their complex life cycle
c. They allow bacteria to transfer plasmids between cells
d. They allow bacteria to form a sticky layer for attachment
a. They allow the bacteria to hide out when growth conditions are bad
If a patient sample is identified as having Gram-negative bacteria, what is one possible area of concern for treating that patient?
a. Treating the disease will require 3-6 months of continuous antibiotic use
b. The bacteria have a cell wall that resists most conventional forms of disinfection
c. Treatment may require special antibiotics that can penetrate the layer of mycolic acid
d. Killing the bacteria might release endotoxins that cause fever and organ stress
d. Killing the bacteria might release endotoxins that cause fever and organ stress
How are prokaryotic and eukaryotic ribosomes different?
a. Prokarotes do not have ribosomes while eukaryotes do.
b. Eukaryotic ribosomes are larger and have a more complex structure.
c. There is no difference; prokaryotic and eukaryotic ribosomes are identical in structure and function
d. Prokaryotic ribosomes are used to make DNA while eukaryotic ribosomes make proteins
b. Eukaryotic ribosomes are larger and have a more complex structure.
Why are Toxoplasma infections in humans typically asymptomatic?
a. Toxoplasma is an opportunistic pathogen only
b. reproduction of the parasite makes the infection much milder
c. Toxoplasma infections only happen on the top layers of the skin
d. the immune system forces the parasite to form dormant cysts in muscle
b. reproduction of the parasite makes the infection much milder
Which of the following statements about yeasts is incorrect?
a. Yeasts are cells that are spherical or oval shaped
b. True yeasts are not pathogens.
c. Yeasts are typically opportunistic pathogens
d. Dimorphic yeasts always live as a single yeast-form cell
c. Yeasts are typically opportunistic pathogens