Survey of Microorganisms: Viruses, Viroids, and Prions

These flashcards cover the essential vocabulary and concepts related to microorganisms, specifically focusing on viruses, viroids, and prions, as discussed in the lecture.

Viruses

Non-living obligate intracellular parasites that replicate only in living cells.

Viroids

Infectious agents consisting of a single piece of RNA without a protective coat.

Prions

Infectious proteins that cause neurodegenerative diseases, consisting of protein only.

Nucleocapsid

Structure formed by nucleic acid and a protein coat in viruses.

Virion

Complete infective form of a virus outside a host cell.

Capsid

Protein shell that encases the viral genome.

Genome

The complete set of genetic material in a virus.

Helical viruses

Viruses with rod-shaped symmetry.

Icosahedral viruses

Viruses with spherical shape, featuring 20 triangular faces.

Complex viruses

Viruses with asymmetric structures, including bacteriophages.

Naked virus

Virus without an envelope, consisting only of nucleic acid and a capsid.

Enveloped virus

Virus with an outer lipid membrane derived from the host cell.

Capsomeres

Protein subunits that make up the capsid.

Viral replication cycle

The process by which a virus infects a host and produces new virions.

Attachment (adsorption)

The first step in the viral replication cycle, where the virus adheres to the host cell.

Penetration

The step where viral nucleic acid enters the host cell.

Synthesis of viral components

The process of replicating viral nucleic acid and proteins inside the host.

Assembly

The stage of the viral replication cycle where new virions are constructed.

Release

The final step of the viral replication cycle, where new virions exit the host cell.

Lytic cycle

Virus cycle resulting in the destruction of the host cell.

Lysogenic cycle

Virus cycle where it integrates its DNA into the host without immediate destruction.

Bacteriophage

A virus that infects bacteria.

SARS-CoV-2

A novel coronavirus responsible for the COVID-19 pandemic.

HIV

Human Immunodeficiency Virus, which can lead to AIDS.

Dengue virus

An RNA virus transmitted by mosquitoes causing Dengue fever.

Hepatitis B

A vaccine-preventable liver infection caused by the hepatitis B virus.

Rabies virus

Virus spread through animal bites, affecting the brain and is often fatal.

Cytopathic effects

Changes in host cells due to viral infection, often observable under a microscope.

Hemagglutination test

A laboratory test for detecting viruses through the clumping of red blood cells.

Plaque assay

A method for quantifying virus particles based on the formation of clear areas in a host culture.

Baltimore classification

Classification of viruses based on their genome type and method of replication.

RNA viruses

Viruses that use RNA as their genetic material.

DNA viruses

Viruses that use DNA as their genetic material.

Carbohydrates in viruses

Molecules found in viral envelopes, often serving as receptors and antigens.

Lipids in viruses

Components found in the viral envelope, derived from host cell membranes.

Glycoproteins

Molecules in viral envelopes that facilitate attachment to host cells.

Cell culture

Method for growing viruses in a controlled environment using live cells.

Embryonated eggs

A method used for cultivating viruses by using fertilized eggs.

Animal models

Use of live animals for studying virus infections and testing treatments.

Vaccination

Administration of a vaccine to induce immunity against viral diseases.

Antigenic properties

Characteristics of a virus that determine the immune response it elicits.

Viral enzymes

Proteins encoded by viruses that facilitate viral replication and assembly.

Antibody

A protein produced by the immune system that binds to specific antigens.

Immune response

The body's defense mechanism against viral infections.

Infectious agents

Microorganisms, including viruses, that cause disease.

Obligate intracellular parasites

Organisms that can only reproduce inside a host cell.

Non-segmented viruses

Viruses whose genome consists of a single continuous piece of nucleic acid.

Segmented viruses

Viruses whose genome is divided into separate pieces.

RNA polymerase

Enzyme that synthesizes RNA from a DNA template in viruses.

Reverse transcriptase

An enzyme used by retroviruses to convert RNA into DNA.

Viral pathogenesis

The process through which a virus causes disease.

Viral transmission

The method by which a virus spreads from one host to another.

Zoonotic infections

Diseases transmitted from animals to humans.

Vaccination strategies

Approaches used to prevent viral infections through immunization.

COVID-19 symptoms

Common signs of infection include fever, cough, and fatigue.

Viroid diseases

Plant diseases caused by viroids, characterized by stunted growth and deformity.

Prion diseases

Neurological disorders caused by infectious prions, such as Mad Cow Disease.

Viral shedding

The release of virus particles from an infected host.

Serological tests

Laboratory tests that detect antibodies or antigens in a sample.

Genome sequencing

Determining the complete DNA or RNA sequence of a virus.

Viral evolution

The process by which viruses change and adapt over time.

Interferon

Proteins produced by host cells in response to viral infections.

Public health measures

Strategies implemented to prevent and control viral outbreaks.

Diagnostic methods

Techniques used to identify viral infections in patients.