Chap 42

Question 1

Antimetabolite

Answer 1

A drug that is either a receptor antagonist or that resembles a normal human metabolite and interferes with its function in the body, usually by competing for the metabolite’s usual receptors or enzymes

Question 2

Dermatophyte

Answer 2

One of several fungi that are often found in soil and infect the skin, nails, or hair of humans

Question 3

Ergosterol

Answer 3

The main sterol in fungal membranes

Question 4

Fungi

Answer 4

A very large, diverse group of eukaryotic microorganisms that require an external carbon source and that form a plant structure known as a thallus. Fungi consist of yeasts and molds

Question 5

Molds

Answer 5

Multicellular fungi characterized by long, branching filaments called hyphae, which entwine to form a complex branched structure known as a mycelium

Question 6

Mycosis

Answer 6

The general term for any fungal infection

Question 7

Pathologic fungi

Answer 7

Fungi that causes mycoses

Question 8

Sterols

Answer 8

substances in the cell membranes of fungi to which polyene antifungal drugs bind

Question 9

Yeasts

Answer 9

Single celled fungi that reproduce by budding

Question 10

amphotericin (Fungizone) Mechanism of Action

Answer 10

Act by binding to sterols (main sterol is erogsterol) in the cell membranes of fungi
Channel forms in the fungal cell membrane that allows potassium and magnesium ions to leak out of the fungal cell
Causes fungal cellular metabolism to be altered, which leads to death of the cell

Question 11

fluconazole (Diflucan) Mechanism of Action

Answer 11

Acts as either fungistatic or fungicidal drugs, depending on their concentration in the fungus
Most effective in combating rapidly growing fungi
Work by inhibiting fungal cell cytochrome P-450 enzymes (needed to produce ergosterol)
Methysterols are produced instead, defect in cell membrane making it leaky
Fungal cells die because they cannot carry on cellular metabolism