Unit 04 · Cell Communication & the Cell Cycle
The big ideas here are how cells receive and respond to signals: signal transduction pathways, feedback that keeps systems in balance, the ordered stages of the cell cycle and mitosis, and what happens when that control fails — cancer. Mastery means reading mitotic stages on a slide and explaining how a signal becomes a cellular response.
| Criterion | Not yet | Approaching | Mastered |
|---|---|---|---|
| Cell cycle & mitosis stages | Cannot order the phases. | Names phases but misorders or mislabels them. | Orders interphase and mitotic phases and describes each. |
| Signal transduction | Unclear how signals reach a cell. | Names reception–response but not the relay between. | Traces reception, transduction, and response in order. |
| Feedback regulation | Confuses positive and negative feedback. | Defines feedback but applies it unevenly. | Predicts how feedback restores or amplifies a condition. |
| Cancer as cycle dysregulation | Sees cancer as unrelated to the cycle. | Links cancer to division without the checkpoint idea. | Explains cancer as lost checkpoint control of the cell cycle. |
| Microscopy of mitotic stages | Cannot find dividing cells. | Finds mitosis but misidentifies stages. | Locates and identifies mitotic stages on a prepared slide. |
| 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. |
“The signal binds a receptor and triggers a relay that ends with the nucleus changing which genes run. The checkpoint stops a cell with damaged DNA from dividing — skip that check, and uncontrolled division is how a tumor begins.”
“Cells send signals to talk. The cell cycle is how they divide. Cancer is when cells grow too much.”
This unit is assessed at the microscope with onion-root or whitefish slides and oral checks where you explain signaling and feedback aloud. A criterion is mastered when you can identify the stages on a real slide and reason about the controls behind them.
A 5-page clipboard packet — unit overview, key terms, the mastery rubric, anchor examples, and a score sheet you can print and grade against.