Chapter 4, Problem 3CT

a.

Summary Introduction

To explain:

A pathogen like Candida albicans is able to cause a more serious form of disease within different areas of the body and why such an infection is difficult to treat.

Concept introduction:

Candida albicans is a species of fungus which infects several species of animals and humans. They are unicellular organisms which form hyphae with mycelium. There is formation of septum between the mycelia which prevent the mixing of cytoplasm between different regions inside the cytoplasm. Fungus such as Candida albicans has various features like formation of bio-films, mycelium and hyphae, switching between various yeast phenotypes and secretion of enzymes like hydrolases which degrade various tissues in the human body during infection.

b.

Summary Introduction

To explain:

Conduction of experimental research and summarize how fungi played a role in Alexander Fleming’s discovery of the first antibiotic compound.

Concept Introduction:

Penicillium form spores of fungi which form dense structures. They form conidiophores. They are present in various forms like globose, elliptical, cylindrical and fusiform.

Summary Introduction

To draw:

A sketch of famous petri dish and describe what aspect of the plate revealed to him that a fungal contaminant was actually providing to him a very valuable biochemical cue.

Concept Introduction:

“Petri plate” is a dish used for growing the species of fungi. The spores of Penicillium are found in soil and grow in damp regions. They cause spoilage of fruits and vegetables. They cause allergic reaction on skin.

Pictorial representation:

Fig. 1: Petri plate showing the inhibition of growth of a bacterium cell by a fungus Penicillium growing in the surroundings.