Microbiology Chapter Review: Eukaryotes, Viruses, Archaea, and Prions

A set of vocabulary flashcards based on the lecture transcript covering fungal classification and pathology, protozoan infections, viral characteristics and life cycles, viroids, prions, and archaeal versus bacterial cellular features.

Saprophytes

Organisms, such as certain fungi, that function as decomposers.

Chitin

A polysaccharide structure found in fungal cell walls, similar to a NAG polysaccharide.

Yeast

Single-celled fungi.

Molds

Multicellular fungi.

Thallus

The body structure of a fungus, which can be broken down into hyphae.

Mycosis

Fungal infections classified as superficial, cutaneous, subcutaneous, systemic, or opportunistic.

Superficial Mycosis

A fungal infection located on the very outer layer of the skin.

Cutaneous Mycosis

A fungal infection found directly on the skin.

Subcutaneous Mycosis

A fungal infection found beneath or under the skin.

Systemic Mycosis

A fungal infection located in the bloodstream.

Opportunistic Pathogen

A pathogen that becomes disease-causing under specific conditions, such as when a host is immunocompromised or lacks resistance.

Dimorphic Fungi

Fungi capable of existing in two forms depending on temperature, growing as molds at room temperature ($25\,\text{degrees Celsius}$) and as yeasts at body temperature ($37\,\text{degrees Celsius}$).

Septate Hyphae

Fungal hyphae that are divided into distinct segments by cross-walls called septums.

Aseptate Hyphae

Fungal hyphae that lack dividing septums.

Histoplasmosis

A dimorphic fungal lung disease transmitted to humans through bird and bat droppings.

Cryptococcosis

A systemic infection caused by the yeast Cryptococcus neophormins, contracted via the inhalation of spores in dried pigeon droppings.

Nosocomial Infection

An infection acquired within a hospital setting.

Candida albicans

A fungal organism that causes oral thrush and serves as a major example of nosocomial candidiasis.

Primary Amoebic Meningoencephalitis (PAM)

A central nervous system infection caused by a brain-eating amoeba protozoan.

Giardia

A zoonotic protozoan infection that forms cysts and interferes with nutrient absorption.

Zoonotic Infection

An infection capable of being transmitted directly from animals to humans.

Malaria

A protozoan disease caused by Plasmodium species, such as Plasmodium falciparum, and spread via mosquito vectors.

African Sleeping Sickness

A protozoan infection transmitted by tsetse flies with cattle and wild animals as reservoirs, utilizing VSG switching to evade immunity.

VSG Switching

A mechanism by which a pathogen alters its surface antigens to prevent host immune identification.

Toxoplasmosis

A protozoan disease spread through the fecal-oral route via cat droppings, posing severe risk to pregnant women.

Virion

The complete viral particle that exists outside a host cell, incapable of independent metabolism or reproduction.

Bacteriophages

Viruses that specifically infect bacteria and do not harm human cells.

Temperate Phage

A bacteriophage capable of undergoing both lytic and lysogenic replication cycles.

Virulent Phage

A bacteriophage that exclusively undergoes the lytic cycle.

Prophage

Viral DNA integrated into the bacterial host chromosome during a lysogenic cycle.

Haemaphilus influenzae

A bacterium that causes meningitis; not the causative agent of the flu.

Antigenic Drift

Small, gradual changes in viral surface antigens, responsible for seasonal flu variations.

Antigenic Shift

Large, sudden changes in viral surface antigens that can lead to disease pandemics.

Viroids

Infectious agents composed of circular single-stranded RNA that infect plants and inhibit translation.

Prions

Misfolded infectious brain proteins causing degenerative central nervous system diseases in humans and animals, possessing no effective treatments.

PRPC

The normal, functional protein form found naturally in the brain.

PRPSC

The misfolded, pathogenic form of the prion protein characterized by an increased concentration of beta sheets.

Pseudomurein

A component of Archaea cell walls containing NAT and NAG.