Chapter 21: Virus

These flashcards cover key concepts, vocabulary, and definitions related to viruses based on the lecture notes.

Virus

An acellular infectious agent that needs a host cell to replicate.

Acellular

Not composed of cells; viruses are considered acellular.

Virion

A complete viral particle that can infect a host cell.

Attachment (Virus Infection Step 1)

The process where a virus binds to a host cell through receptor molecules.

Entry (Virus Infection Step 2)

The stage at which the virus enters the host cell.

Replication (Virus Infection Step 3)

The process where the virus's genetic material is copied and new proteins are synthesized.

Egress (Virus Infection Step 4)

The release of new virions from the host cell.

Lytic Cycle

A viral life cycle where the virus destroys the host cell after replication.

Lysogenic Cycle

A viral life cycle where the virus integrates its DNA into the host's genome without killing the host.

Bacteriophage

A virus that infects bacteria.

RNA Virus

A virus that has RNA as its genetic material.

DNA Virus

A virus that has DNA as its genetic material.

Plant Virus

A virus that primarily infects plant cells.

Animal Virus

A virus that primarily infects animal cells.

Prion

An infectious protein that causes neurodegenerative diseases.

Viroid

A small circular RNA molecule that infects plants.

Vaccine

A biological preparation that provides active acquired immunity to a particular infectious disease.

Antiviral Drug

A medication used specifically to treat viral infections.

Horizontal Transmission (Plant Virus)

Transfer of a virus from one plant to another, typically through damaged tissue.

Vertical Transmission (Plant Virus)

Transmission of a virus from parent plant to offspring.

Naked Virus

A virus without an envelope, can enter host cells by direct penetration or endocytosis.

Enveloped Virus

A virus that has a lipid bilayer membrane surrounding its capsid.

Baltimore Classification

A system that classifies viruses based on their mRNA production during the replicative cycle.

HIV

Human Immunodeficiency Virus, which infects immune cells and can cause AIDS.

Influenza Virus

A virus that causes flu and can be treated with antiviral drugs like Tamiflu.

Transmission

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

Epidemiology

The study of how diseases spread and can be controlled.

Symptoms

Physical or mental features that indicate a condition or disease.

Acute Disease

An illness characterized by sudden onset and a short period of illness.

Chronic Infection

A long-lasting viral infection that can persist for years.

Oncogenic Virus

A virus that can cause cancer.

Prophage

Viral DNA that is integrated into the bacterial chromosome during the lysogenic cycle.

Genomic RNA

The genetic material of RNA viruses used in replication.

Transcription

The process of synthesizing RNA from a DNA template.

Mutation Rate

The frequency at which a virus's genetic material changes.

Ribonucleic Acid (RNA)

A molecule essential for coding, decoding, regulation, and expression of genes.

Deoxyribonucleic Acid (DNA)

A molecule that carries most genetic instructions for the development and functioning of living organisms.

Budding

A process by which enveloped viruses exit the host cell without lysing it.

Neuraminidase

An enzyme that helps viruses, such as influenza, to exit the host cell.

Endocytosis

A cellular process in which substances are brought into the cell.

Receptor

Molecules on the surface of host cells that viruses bind to for entry.

Non-enveloped Virus

A virus that does not have an outer lipid membrane.

Viral Proteins

Proteins produced by viruses using the host cell's machinery.

Host Cell Machinery

The cellular components and structures viruses hijack to replicate.

Crop Failure

A decrease in agricultural yield, often caused by viral infections in plants.

Hyperplasia

Abnormal increase in the number of cells, often associated with viral infection symptoms.

Hypoplasia

The incomplete development or underdevelopment of a tissue or organ, sometimes due to viral infections.

Necrosis

Death of tissue, often resulting from viral infections.