Viruses and Bacteria Flashcards

Flashcards for reviewing Viruses and Bacteria lecture notes.

What is a capsid?

A protein coat that covers and protects the genome of a virus.

What is the genome of a virus?

DNA or RNA, single-stranded or double-stranded.

What is an envelope in a virus?

A former host cell membrane surrounding the capsid of a virus.

What are ligands?

Surface proteins on a virus that fit to receptor molecules on a host cell.

What is the first step of the lytic cycle: attachment?

The virus attaches itself to the host cell.

What is the second step of the lytic cycle: entry?

The virus injects the nucleic acid into the cell.

What is the third step of the lytic cycle: replication?

Virus DNA breaks down the host DNA and takes over, instructing the cell to make virus parts.

What is the fourth step of the lytic cycle: assembly?

Virus parts are put together into new viruses.

What is the fifth step of the lytic cycle: release?

When viruses are mature, they come out of the cell, destroying it, and start to infect other cells.

What happens during the lytic cycle?

Host cell bursts, releasing new viruses into the host's system.

What happens during the lysogenic cycle?

Virus combines its DNA into the host cell's DNA.

What is the second step of the lysogenic cycle: entry?

The virus injects the nucleic acid into the cell.

What happens during the third step of the lysogenic cycle: integration?

Virus DNA becomes part of the host cells DNA.

What happens during the fourth step of the lysogenic cycle: replication?

Host cell is replicated with viral DNA.

What is the purpose of reverse transcriptase in retroviruses?

The virus uses reverse transcriptase for transcribing viral RNA into a DNA copy.

What is a prion?

Infectious particle made only of protein that can cause other proteins to fold incorrectly.

What is a viroid?

Single-stranded RNA without a protein coat that causes disease in plants.

What is COVID-19?

Coronavirus disease that emerged in 2019.

What is the function of eaters or macrophages?

Eats pathogens.

What is the function of helpers or T-helper cells?

Tell the immune system to build a clone army.

What is the function of killers or T-killer cells?

Kill the virus or pathogen.

What is the purpose of vaccines?

A practice run for the immune system.

What are the two main groups of bacteria?

Archaea and Eubacteria.

What classifies archaea bacteria?

Oldest bacteria, some are methanogens, halophiles and thermoacidophiles.

What is the role of nitrogen fixation?

Convert atmospheric nitrogen to usable compounds.

What is a flagellum?

A whip-like tail used for movement in bacteria.

What is a capsule?

A gelatinous smokescreen used for hiding from host defenses in bacteria.

What is the purpose of a cell wall?

Provides support for a bacteria cell.

What is a pilus?

Tiny tubes that look like hairs used to transfer plasmids in a process called conjugation.

What happens during binary fission?

One bacteria splits into two bacteria.