Fungi

Question 1

What are the two types of fungi

Answer 1

Molds and Yeast

Question 2

are fungi eukaryotic or prokaryotic

Answer 2

eukaryotic

Question 3

are fungi aerobic or anaerobic

Answer 3

can be aerobic or anaerobic, but mostly aerobic

Question 4

What temps and pH do fungi like and why?

Answer 4

human pathogenic fungi prefer 35-37°C and pH 4.0 – 4.5 (acidic); this prevents bacterial growth

Question 5

Define dimorphic

Answer 5

fungi that can morph from yeast-like to mold-like

Question 6

what are 3 differences between molds and yeast

Answer 6

yeast: single celled, spherical, and reproduce asexually Molds: multicellular. filamentus hyphae, reproduction by spores/sexual

Question 7

What are the 8 structures of a yeast cell

Answer 7

Nucleus, Membrane, Cell wall, Mitochondria, Lipid Granule, Bud Scar, Vacuole, Phosphate Granules

Question 8

Yeast cells stain gram positive or negative

Answer 8

positive (blue)

Question 9

what chemical stains yeast cells

Answer 9

Methylene Blue

Question 10

Why can Methylene Blue only work on dead yeast cells

Answer 10

live ones have an enzyme which breaks down the stain into colourless products

Question 11

What are the 5 steps of gram staining yeast

Answer 11

1. Choose beaker A or B.
2. Place a drop of the yeast culture on a clean microscope slide. Cover with a cover slip.
3. Place a drop of methylene blue stain on one side of the preparation.
4. 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.
5. Repeat steps 2-4 for the preparation in the other beaker.

Question 12

can a zombie apocalypse happen?

Answer 12

fungus infection is very species specific, unlikely to jump from species to humans

Question 13

explain the process of alcohol fermentation

Answer 13

Yeast convert sugar into energy and CO2 and Alcohol are bi-products

Question 14

What are the three categories of fungal infection

Answer 14

Superficial, Subcutaneous, System

Question 15

What does superficial infection mean

Answer 15

localised to skin, hair, and nails

Question 16

what does subcutaneous infection mean

Answer 16

infection confined to dermis or just under the skin

Question 17

What does systemic infection mean

Answer 17

deep infections of internal organs

Question 18

What is the genus “Tinea” known for

Answer 18

responsible for most of superficial mycoses. Tinea can infect various sites of the body, but commonly the toes and the groin.

Question 19

What is tinea pedis and what type of infection is it. Descripe the infection

Answer 19

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.

Question 20

What is tinea cruris and what type of infection is it. Describe the infection

Answer 20

Jock Itch: Superficial. Jock itch also thrives in humid, warm areas of the groin area, producing an itchy fungal skin infection.

Question 21

What is tinea ringworm and what type of infection is it. Describe the infection

Answer 21

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.

Question 22

What is tinea unguium and what type of infection is it. Describe the infection

Answer 22

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.

Question 23

What is Sporotrichosis and what type of infection is it. Describe the infection

Answer 23

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.

Question 24

What are Systemic Mycoses and what are the two ways it infects

Answer 24

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

Question 25

What is a primary pathogenic Fungi

Answer 25

Infection occurs in previously healthy persons and arises through the respiratory route

Question 26

What is an exmaple of primary pathogenic fungi, describe it

Answer 26

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.

Question 27

What is an opportunistic fungi

Answer 27

patients usually have some serious immune defect or have undergone surgery.

Question 28

what is an example of opportunistic fungi, describe it

Answer 28

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.

Question 29

What are two ways to break chain of infection from target #1 susceptible host

Answer 29

personal hygiene and prophylaxis: avoid damp and humid places, ensure proper blood circulation

Question 30

What are our 3 immune defences against fungal infection

Answer 30

1. non-disease causing bacteria that deprive harmful fungi of space and nutrients, thereby keeping them in check.
2. 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.
3. High acidity levels in some environments such as the vagina provide another layer of protection.

Question 31

what are two ways to break chain of infection at means of transmission (fungus)

Answer 31

1. keep Nail & Skin Injury or Infection clean 2. good hygiene

Question 32

What are 4 methods of treatment for a fungal infection

Answer 32

antifungal cream, ointment, suppository, probiotics, garlic