Which is NOT an example of bacteria?

Analyze the question: You are asked to pick the one option that is not a bacterium (or a bacterial form).

Concept: Bacteria are classified mainly by shape:

• Bacilli – rod-shaped (e.g. Bacillus anthracis)
• Cocci – spherical or round (e.g. Staphylococcus)
• Diplococci – cocci arranged in pairs (e.g. Neisseria, which causes gonorrhoea and meningitis)
• Spirilli – spiral or corkscrew-shaped (e.g. Spirillum)
• Vibrios – comma-shaped (e.g. Vibrio cholerae)

Step-by-step solution:

1. Bacilli are rod-shaped bacteria, so A is a bacterium.
2. Cocci are spherical bacteria, so B is a bacterium.
3. Diplococci are paired cocci, so C is a bacterium.
4. Spirilli are spiral bacteria, so D is a bacterium.
5. Sporangia (singular: sporangium) are spore-containing sacs found in fungi such as Rhizopus (bread mould) and Mucor, and also in ferns. They are not bacteria.

Answer: E, sporangia.

Tip: Bacterial shape names end in -cocci, -bacilli, -spirilli, -vibrios. If you see a word with "sporangi-", think of fungi (e.g. Rhizopus) or ferns. Don't confuse it with bacterial "endospores", which are a survival structure and not a sporangium.