Unit 07 · Microorganisms: Protists, Algae & Bacteria
This unit puts something alive under the scope. You make a wet mount straight from pond water or a culture and hunt for organisms that swim, drift, and dart across the field — protists, algae, and bacteria — learning to track a moving target and tell a living cell from a fleck of debris. Mastery here is not something you can explain your way into. An instructor watches you mount, find, and follow, and the organism crossing the field is the proof.
| Criterion | Not yet | Approaching | Mastered |
|---|---|---|---|
| Making a living wet mount | Uses too much water or crushes the coverslip so organisms wash away or die. | Mounts pond water but floods the slide, letting everything drift too fast to follow. | Draws a small drop from the bottom of the sample, mounts it under a coverslip, and keeps enough organisms alive and in view to observe. |
| Finding & tracking motile protists | Cannot spot a moving organism or loses it the instant it swims. | Sees something move but cannot follow it with the stage. | Locates and tracks a motile protist — amoeba, paramecium, or euglena — steering the stage to keep it in the field. |
| Recognizing algae | Cannot tell algae from other green material. | Suspects algae but cannot point to the feature that marks it. | Recognizes algae by their chloroplasts and form and separates them from plant debris in the mount. |
| Recognizing bacterial shapes | Cannot make out bacteria or tell one shape from another. | Sees tiny specks but cannot classify them as rod, sphere, or spiral. | Identifies bacterial shape — rod, coccus, or spiral — under high power and distinguishes it from stray particles. |
| Distinguishing organisms from debris & handling cultures safely | Calls every speck an organism and handles live cultures carelessly. | Tells some organisms from debris but is loose with culture hygiene. | Separates living, moving organisms from drifting debris and handles and disposes of live cultures safely. |
| Integration (cross-domain) | Treats the science as isolated facts; makes no cross-domain connection. | Names a link to history, reading, or writing but cannot defend why it matters. | Connects the unit to its anchor across History · Reading · Writing (plus chosen electives) and defends why the connection matters. |
“I took a drop from the bottom of the jar where the sediment was, kept it small so it wouldn’t race around, and covered it. On 10× I caught a paramecium and drove the stage to chase it across the field. The green clumps that just sat there were algae — I could see their chloroplasts — not swimmers.”
“I put a big drop on and everything was flying everywhere. Some black dots were maybe alive? I couldn’t keep anything in the circle long enough to tell.”
You demonstrate this module by doing it — an instructor watches you make a living wet mount and find and track real organisms, not a multiple-choice test. A criterion counts as mastered only when you can hold a moving organism in view, name what it is, and handle the culture safely. Mastery is demonstrated, not awarded.
A 5-page clipboard packet — unit overview, key terms, the mastery rubric, anchor examples, and a score sheet you can print and grade against.