Fungi Flashcards
What are the two types of fungi
Molds and Yeast
are fungi eukaryotic or prokaryotic
eukaryotic
are fungi aerobic or anaerobic
can be aerobic or anaerobic, but mostly aerobic
What temps and pH do fungi like and why?
human pathogenic fungi prefer 35-37°C and pH 4.0 – 4.5 (acidic); this prevents bacterial growth
Define dimorphic
fungi that can morph from yeast-like to mold-like
what are 3 differences between molds and yeast
yeast: single celled, spherical, and reproduce asexually Molds: multicellular. filamentus hyphae, reproduction by spores/sexual
What are the 8 structures of a yeast cell
Nucleus, Membrane, Cell wall, Mitochondria, Lipid Granule, Bud Scar, Vacuole, Phosphate Granules
Yeast cells stain gram positive or negative
positive (blue)
what chemical stains yeast cells
Methylene Blue
Why can Methylene Blue only work on dead yeast cells
live ones have an enzyme which breaks down the stain into colourless products
What are the 5 steps of gram staining yeast
- Choose beaker A or B.
- Place a drop of the yeast culture on a clean microscope slide. Cover with a cover slip.
- Place a drop of methylene blue stain on one side of the preparation.
- Using a small piece of paper towel, place the paper towel on the opposite side from the stain. The paper towel will soak up moisture in the preparation and draw the methylene blue into the yeast area.
- Repeat steps 2-4 for the preparation in the other beaker.
can a zombie apocalypse happen?
fungus infection is very species specific, unlikely to jump from species to humans
explain the process of alcohol fermentation
Yeast convert sugar into energy and CO2 and Alcohol are bi-products
What are the three categories of fungal infection
Superficial, Subcutaneous, System
What does superficial infection mean
localised to skin, hair, and nails
what does subcutaneous infection mean
infection confined to dermis or just under the skin
What does systemic infection mean
deep infections of internal organs
What is the genus “Tinea” known for
responsible for most of superficial mycoses. Tinea can infect various sites of the body, but commonly the toes and the groin.
What is tinea pedis and what type of infection is it. Descripe the infection
Atheletes Foot. Superficial. Athlete’s foot thrives in the warm and humid area between the toes causing itching, scaling, peeling, or cracking of the skin.
What is tinea cruris and what type of infection is it. Describe the infection
Jock Itch: Superficial. Jock itch also thrives in humid, warm areas of the groin area, producing an itchy fungal skin infection.
What is tinea ringworm and what type of infection is it. Describe the infection
Ringworm: supericial. a fungal infection that typically affects the skin and scalp. It usually starts as a reddish, itchy, scaly rash. Over time, it gets larger and forms a red ring.
What is tinea unguium and what type of infection is it. Describe the infection
Fungal Nail Infection: Superficial: This is a very common fungal infection of the nail and nail bed. As it spreads deeper, it changes the shape and color of the nail, and the nail becomes thicker and more brittle. It is often painful and recurrent.
What is Sporotrichosis and what type of infection is it. Describe the infection
infections confined to the dermis: Subcutaneous: Infection may arise following the wounding of the skin and the introduction of vegetable matter (which has yeast on it). These mycoses are rare and confined mainly to tropical regions. They tend to be slow in onset and chronic in duration.
What are Systemic Mycoses and what are the two ways it infects
These are invasive infections of the internal organs with the organism gaining entry by the lungs, gastrointestinal tract or through intravenous lines. They may be caused by: (i) primary pathogenic fungi or (ii) by opportunistic fungi
What is a primary pathogenic Fungi
Infection occurs in previously healthy persons and arises through the respiratory route
What is an exmaple of primary pathogenic fungi, describe it
Histoplasmosis: Infection occurs in previously healthy persons and arises through the respiratory route. As spores are inhaled, the lungs are often the main site of infection but dissemination to the liver, heart and central nervous system can occur.
What is an opportunistic fungi
patients usually have some serious immune defect or have undergone surgery.
what is an example of opportunistic fungi, describe it
Thrush: Candida albicans is a yeast causing “thrush” in humans. Normally a superficial mycoses, candidiasis typically infects the mouth, vagina or urinary tract and it is part of the normal flora of the vagina and gastrointestinal tract.
However, during times of ill health or impaired immunity, the organism multiplies rapidly and can cause systemic disease. Antibiotic treatment can also alter the normal bacterial flora allowing C. albicans to flourish.
What are two ways to break chain of infection from target #1 susceptible host
personal hygiene and prophylaxis: avoid damp and humid places, ensure proper blood circulation
What are our 3 immune defences against fungal infection
- non-disease causing bacteria that deprive harmful fungi of space and nutrients, thereby keeping them in check.
- The primary barriers we have against fungal infections are the same as those for other infections:
intact skin, naturally occurring chemicals and mucus produced by our body, competition with normal bacteria that live on us, and the turnover rate of our skin cells. - High acidity levels in some environments such as the vagina provide another layer of protection.
what are two ways to break chain of infection at means of transmission (fungus)
- keep Nail & Skin Injury or Infection clean 2. good hygiene
What are 4 methods of treatment for a fungal infection
antifungal cream, ointment, suppository, probiotics, garlic
