virology and mycology Flashcards
key concepts of virology and mycology
Virology & Viral Structure
What is virology?
The study of viruses.
Virology & Viral Structure
What are the key characteristics of viruses?
Non-cellular, biologically inert, obligate intracellular parasites, cannot reproduce independently, infect all life forms, not visible with a light microscope.
Virology & Viral Structure
What is a virion?
A fully developed infectious viral particle.
Virology & Viral Structure
What are the two main components of a virion?
Nucleic acid core and a protein coat (capsid).
Virology & Viral Structure
What is a capsid made of?
Protein subunits called capsomeres.
Virology & Viral Structure
What is a nucleocapsid?
Combination of the nucleic acid and capsid.
Virology & Viral Structure
What is a viral envelope?
A lipid membrane surrounding some viruses
Which characteristics do viruses lack compared to bacteria?
No plasma membrane, no binary fission, no ribosomes, no ATP metabolism, no sensitivity to antibiotics.
Viral Morphology
What are the four types of viral morphology?
Icosahedral, enveloped, helical, and complex.
Viral Morphology
Describe an icosahedral virus.
Spherical virus with a geometric shape of 20 triangular faces.
Viral Morphology
Describe an enveloped virus.
Surrounded by a lipid membrane containing proteins and carbohydrates.
Viral Morphology
Describe a helical virus.
Rod-shaped, can be rigid or flexible, genome inside a cylindrical capsid (e.g., Ebola).
Viral Morphology
Describe a complex virus
Has more complicated structures (e.g., bacteriophage with an icosahedral head and helical tail).
Viral Genomes & Baltimore Classification
What genetic material can viruses have?
DNA or RNA, but never both simultaneously.
Viral Genomes & Baltimore Classification
What are the types of viral genomes?
Single-stranded (ss) or double-stranded (ds), linear or circular.
Viral Genomes & Baltimore Classification
What is the Baltimore Classification System?
A system classifying viruses based on their genetic material.
Viral Genomes & Baltimore Classification
How many groups exist in the Baltimore Classification System?
Seven
Viral Genomes & Baltimore Classification
What are the key Baltimore groups?
Group I: dsDNA, Group II: ssDNA, Group III: dsRNA, Group IV: (+) ssRNA, Group V: (-) ssRNA, Group VI: ssRNA with DNA intermediate, Group VII: dsDNA with RNA intermediate.
Bacteriophage & Lifecycle
What is a bacteriophage?
A virus that infects bacteria.
Bacteriophage & Lifecycle
What are the two bacteriophage life cycles?
Lytic and lysogenic.
Bacteriophage & Lifecycle
What happens in the lytic cycle?
Virus replicates and lyses (kills) the host cell.
Bacteriophage & Lifecycle
What happens in the lysogenic cycle?
Virus integrates into the host genome and remains dormant as a prophage.
Bacteriophage & Lifecycle
What triggers lysogenic viruses to enter the lytic cycle?
Host stress, DNA damage, or nutrient deprivation.
Animal Viruses
How do animal viruses differ from bacteriophages?
The entire virion enters the host, and many replicate in the nucleus.
Culturing & Detecting Viruses
How are viruses cultured?
Using host cells (bacterial culture for bacteriophages, tissue culture for animal viruses).
Culturing & Detecting Viruses
What is a plaque assay?
A method to count infectious virus particles using clear zones (plaques) on a host cell lawn.
Fungi Characteristics
Are fungi prokaryotic or eukaryotic?
Eukaryotic.
Fungi Characteristics
What are key structural features of fungi?
Chitin cell walls, ergosterol in membranes.
Fungi Characteristics
What are the three main types of fungi?
Yeasts (unicellular), moulds (multicellular with hyphae), and dimorphic fungi (switch between yeast and mould forms).
Fungal Reproduction
How do fungi reproduce asexually?
Via spores like conidia and sporangia.
Fungal Reproduction
How do fungi reproduce sexually?
Through meiosis to produce genetically diverse spores (e.g., zygospores, ascospores).
Fungi in Health & Disease
What is the WHO Fungal Priority Pathogen List (FPPL)?
A global effort to identify and prioritize fungal pathogens.
Fungi in Health & Disease
What are mycoses?
Fungal infections classified by depth and tissue affected.
Fungi in Health & Disease
What are the five types of mycoses?
Superficial, cutaneous, subcutaneous, systemic, and opportunistic.
Fungal Toxins (Mycotoxins)
What are mycotoxins?
Toxic secondary metabolites produced by fungi.
Fungal Toxins (Mycotoxins)
How do mycotoxins impact health?
They contaminate food and the environment, causing health risks in humans and animals.
