Micro II Exam 7

single-celled eucaryotic organisms

reproduce by budding

multi-cellular eucaryotic organisms

they grow in slender thread-like strands call hyphae

a visible mass of hyphae growing together

reproduce by conidia (asexual) or zygote formation (sexual)

any infection of the skin, hair, or nails with a fungus

most often refers to ringworm, athlete's foot, jock itch or tinea infections

caused by the genera:
    Epidermophyton
    Microsporum
    Trichophyton

all are molds

transmitted via direct contact with infected people or pets

most often affects children under 12 years of age

caused by a mold called Coccidioides immitis

a normal flora organism of the soil

transmitted via inhalation of dust containing the spores

causes influenza-like infection with:
   cough
   painful breathing
   malaise
   loss of appetite

may disseminate to the rest of the body, often causing a form of meningitis

caused by Histoplasma capsulatum

a dimorphic organism

it grows as a yeast above 35⁰C and a mold below

the most common respiratory disease caused by a fungus

the organism is most often found in the soil especially that contaminated with bird or bat droppings

transmitted via inhalation

asymptomatic in most cases

symptomatic cases range from mild respiratory infection with fever to a lethal disseminated (spread throughout the body) infection

most common in the Mississippi, Missouri & Ohio river valleys

caused by Candida albicans

a normal flora organism

most often causes thrush & vaginal yeast infection

may also disseminate throughout the body where it settles in the lungs

can be fatal

caused by Cryptococcus neoformans

most often found in the soil especially that contaminated with pigeon droppings

affects the lungs first but then spreads to the central nervous system

causes a very deadly form of Meningitis

a very serious condition in immunocompromised individuals

caused by Aspergillus sp.

common in decaying vegetation, particularly common in the agriculture industry

the condition resembles TB & is often misdiagnosed

affects immunocompromised individuals most often

caused by Blastomyces dermatitidis

a dimorphic organism

it grows as a mold in the soil & as a yeast in tissue

it forms a lesion in the lung that is granulomatous & suppurative in nature

also often misdiagnosed as TB

if untreated, it will rapidly prove fatal

causes Pneumocystic pneumonia

this is not a pathogen of healthy humans

it affects only immunocompromised individuals

characterized by fever, nonproductive cough and shortness of breath

can lead to death by respiratory failure

often seen as a determining factor for an AIDS diagnosis

Eucaryotic single celled animals

may exist as free-living organisms or as parasites of a living host

differ from other parasites in that they are small enough to necessitate the use of a microscope whereas the others are macroscopic

causes Amebiasis (Amebic dysentery)

most cases are asymptomatic

most common in developing countries with poor sanitation conditions

transmitted via the fecal-oral route

has two stages to its life cycle

Entamoeba histolytica has two stages to its life cycle

this is the form that is passed from the intestine and then reintroduced into another host

this is the stage that occurs in the intestines of a host

feeds on the contents of the intestine as well as the tissue of the intestinal wall

this is what leads to the symptoms of amoebiasis:
     abdominal pain
     fever
     bloody mucoid stool

may spread to other parts of the body
     most commonly the liver

causes Giardiasis

a common gastrointestinal disturbance

transmitted in water contaminated with fecal matter from an infected individual or by person-to-person contact

the latter occurs often in institutional settings like daycare centers & nursing homes

campers and hikers tend to be at heightened risk

has a cyst stage and a trophozoite stage

the most common symptoms are:
Diarrhea
abdominal cramps
increased gas
bloating
weight loss
weakness
foul greasy stools

causes malaria

transmitted to humans via the bite of an infected Anopheles mosquito

has a multiple phase life cycle as well

reproduces asexually in humans

reproduces sexually in the salivary glands of the mosquito

is passed back and forth between humans & mosquitoes

the protozoa localize in the erythrocytes of the human host

causes their destruction

possibly to the point of anemia

the disease is characterized by alternating periods of chills and fever

once attempted to control the disease by controlling the mosquito vector with insecticides

causes toxoplasmosis

infections of the eye and brain in immunocompromised individuals

asymptomatic in most other cases

Toxoplasma gondii transmitted in two ways:

causes trichinosis

an intestinal disturbance while the worms are still in the intestine

trichinosis charateristics:

a more systemic infection as the worms encyst in other areas of the body

trichinosis

transmitted by eating undercooked meat, usually pork

the worms survive by invading a cell and using the cell much like a virus

occurs mainly in muscle cells

A normal flora organism of the soil.

A normal flora fungus of humans.

Affects only immunocompromised individuals.

Affects the lungs then spreads to the central nervous system.

Anopheles mosquito.

Are the three genera of fungi that cause dermatomycosis molds or yeasts?

Campers and hikers are at heightened risk.

Causes a deadly form of meningitis.

Causes an influenza-like infection with cough, painful breathing, malaise, and loss of appetite.

Causes infections of the eye and brain immunocompromised individuals.

Common in decaying vegetation.

Dessemination to the entire body often leads to a form of meningitis.

Disease is characterized by alternating periods of chills and fever.

Eucaryotic single-celled animals.

Explain the dimorphism of Blastomyces dermatitidis.

Explain the dimorphism of Histoplasma capsulatum.

Feeds on the contents of the intestine and the tissues of the intestinal wall.

Forms a lesion that is granulomatous and suppurative in nature.

Found in soil contaminated with bird or bat droppings.

Found in soil contaminated with pigeon droppings.

Has a cyst stage and a trophozoite stage.(2)

How do molds grow?

Is reproduction by conidia sexual or asexual?

ls reproduction by zygote formation sexual or asexual?

Localizes in the erythrocytes of the human host.

Most common in the Mississippi, Missouri, and Ohio river valleys.

Multi-cellular eukaryotic organisms.

NOT a pathogen of healthy humans.

Often affects the agricultural industry.

Often occurs in institutional settings like daycare centers and nursing homes.

Reproduce by conidia.

Reproduce by zygote formation.

Reproduces sexually and asexually.

Resembles tuberculosis. (2)

Seen as a determining factor for an AIDS diagnosis.

Single-celled eukaryotic organisms.

The most common respiratory disease caused by a fungus.

Transmitted by eating meat contaminated with the cysts.

Transmitted by ingesting oocysts excreted by an infected cat.

Transmitted in water contaminated with fecal matter.

What are the three genera of fungi that cause dermatomycosis?