LAB 12: BACTERIA, PROTISTS, AND FUNGI

These flashcards cover key concepts related to bacteria, their classification, and staining techniques discussed in the laboratory on bacteria, protists, and fungi.

Bacteria

Microscopic, single-celled organisms found all over the world.

Cell Wall

The structural layer surrounding bacterial cells; can be thick (Gram-positive) or thin (Gram-negative).

Cocci

Spherical-shaped bacteria.

Bacilli

Rod-shaped bacteria.

Spirilli

Spiral or helical shaped bacteria.

Gram Staining Technique

A method to classify bacteria based on the composition of their cell walls and their ability to absorb specific stains.

Crystal Violet

A stain used in Gram staining that is absorbed by Gram-positive bacteria, causing them to appear purple.

Safranin

A counterstain used in Gram staining that stains Gram-negative bacteria pink/red.

Gram-positive

Bacteria that appear purple after Gram staining due to a thick peptidoglycan cell wall.

Gram-negative

Bacteria that appear pink/red after Gram staining due to a thin or nonexistent peptidoglycan cell wall.

Cyanobacteria

A group of large, Gram-negative, photosynthetic bacteria that often live in water or moist environments.

Nostoc

A genus of cyanobacteria that can exist as colonies or filaments and is able to fix nitrogen.

Oscillatoria

A genus of filamentous cyanobacteria that oscillates to orient towards a light source.

Filamentous

Bacteria that form long, thread-like structures.

Colonial

Bacteria that exist in groups or colonies.

Single-celled

Bacteria consisting of a single cell.

Peptidoglycan

A polymer that makes up the thick cell wall of Gram-positive bacteria.