Microbiology Multiple Choice Questions

The first organisms on Earth were likely microscopic, single-celled _______.

• Eukaryotes

• Prokaryotes

• Protists

• Fungi

The word “prokaryote” comes from Greek meaning _______.

• True nucleus

• Before nucleus

• With membrane

• Without cell wall

Prokaryotes lack a _______.

• Cell wall

• Ribosome

• Nucleus

• Plasma membrane

Archaea live mainly in _______ environments.

• Cold

• Tropical

• Extreme

• Shady

Bacteria and archaea differ because archaea lack _______.

• DNA

• Peptidoglycan

• Cytoplasm

• Ribosomes

Methanogens produce _______ as a waste product.

• Carbon dioxide

• Methane

• Oxygen

• Nitrogen

Halophiles thrive in environments with _______.

• Low pH

• High salt

• Low temperature

• High oxygen

Thermoacidophiles live in environments that are both _______ and _______.

• Cold; acidic

• Hot; acidic

• Wet; neutral

• Dry; basic

Bacteria have cell walls containing _______.

• Cellulose

• Peptidoglycan

• Chitin

• Lignin

Gram-positive bacteria have _______ peptidoglycan and appear _______ when stained.

• Thin, pink

• Thick, purple

• Thin, blue

• Thick, pink