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BBacteriophages: what they are

Bacteriophages — Viruses that infect bacteria — Earth's most abundant biological entities, and a concept-level idea in medicine.

At a glance
Score intensity

Darker cells mean a higher score for this topic on that metric.

Last reviewed Sources & creditsMedia creditsMethodology

Quick answers

Where should I start with Bacteriophages?

Read Identity → How they live → Body & health, then use compare rails.

Is this page advice for Bacteriophages?

Public-health education — not a care plan, prescription, or outbreak briefing.

What does the local lens add?

It names everyday desks for Tree of microbes before English norms look universal.

Are the scores a ranking of Bacteriophages?

No — editorial 0–100 browsing aids inside this atlas only.

How do I compare Bacteriophages to neighbours?

Use related cards and best-of / quiz rails after the first three chapters.

Which chapter is densest?

How they live and Body & health carry mechanisms; skim Identity first.

Start with this section - Identity

A bacteriophage, or phage, is a virus with a bacterial host. Many look like lunar landers: an icosahedral head of DNA, a tail, fibres that match one species or even one strain.

They are not bacteria, not immune cells, and not a household disinfectant brand. They are predators in the microbial food web — conceptually they 'eat' bacteria by hijacking them.

Bacteriophages
Dr. Victor Padilla-Sanchez, PhD https://www.drvictorpadillasanchez.com · CC BY-SA 4.0 · Wikimedia Commons

Traits

Architecture

Viral, not cellular

A capsid plus a genome. No ribosomes. Replication happens only inside a bacterial cell.

Ecology

Host specific

T4 infects certain E. coli; it does not run a human cold. Specificity is the whole point.

Lifestyle

Lytic or temperate

Lytic phages burst the cell. Temperate phages may sit as prophage DNA until a stress cue.

Abundance

Earth's majority vote

Estimates near 10^31 phage particles — outnumbering bacterial cells in many waters.

Evolution

CRISPR memory

Bacteria keep snippets of past phage genomes. That discovery (2007 experimental punch) remade genetics — described here, not instructed.

Gene traffic

Transduction (concept)

Phages can accidentally move bacterial DNA between cells. That is how textbooks explain some resistance spread — not a protocol.

Phage therapy is a century-old idea now back in research headlines. This page stays at the concept level — no treatment recipes.

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