Bacteria, Fungi, and Viruses – Key Concepts

A set of flashcards covering the distinguishing features of bacteria, fungi, and viruses, including structure, nutrition, reproduction, and classification.

What major cellular feature distinguishes bacteria from all other organisms?

Bacteria lack a nucleus.

Why do scientists think bacteria were the first kinds of organisms to evolve?

The oldest known fossils belong to the Kingdom Bacteria.

Can any bacteria perform photosynthesis?

Yes, some bacteria are capable of photosynthesis.

For many years fungi were classified as plants. What key difference shows they should be in their own kingdom?

Fungi lack chlorophyll and do not photosynthesise.

How do fungi obtain their food?

Fungi feed saprophytically or parasitically on organic material such as faeces, human foods, and dead plants or animals.

What are hyphae and what do many hyphae collectively form?

Hyphae are long tube-like structures; collectively they form a mycelium.

What specialised fungal structures produce spores and can be visible as mushrooms?

Fruiting bodies.

Why are viruses not classified as living organisms?

They do not show all seven life processes and cannot function or reproduce outside a host cell.

What happens when a virus enters a living cell?

It hijacks the cell’s machinery to make new viruses, which eventually burst out, killing the host cell.

List four types of molecules commonly found in a virus particle.

Proteins, nucleic acids (DNA or RNA), lipids, and carbohydrates.

Compared with bacteria, how large are viruses?

Viruses are about 100 times smaller than bacteria.

What is the protein coat surrounding a virus’s genetic material called?

A capsid.

What is the only life process that viruses carry out, and where does it occur?

Reproduction, and it occurs only inside a host cell.

Name two examples of viruses mentioned in the notes.

Bacteriophage and influenza virus.

What type of genetic material can be found inside a virus: DNA, RNA, or both?

A virus can contain either DNA or RNA—but not both—inside its capsid.