Grade 8 · Cells · Cells and Organization
Follow Materials Through a Cell
Cells are the basic units of life. Their components perform related functions, while diffusion and osmosis move substances across cell membranes without the cell acting like an empty bag.
Visual model
See how the ideas connect
Apply cell theory
Compare plant and animal cells
Connect organelles transport tissues and systems
Cells and Organization
For students
Notice, predict, explain
Choose one part of the model. Predict how it connects to another part, then use the lesson evidence to explain your thinking.
For teachers
Pause for science talk
Show the model before the explanation. Ask “What do you notice?” and “What might change?” Then revisit student ideas after the worked example.
The big idea
Cell structures cooperate to maintain life processes
A cell's membrane regulates exchange, organelles transform and use materials, and specialized cells work together in tissues, organs, and systems in multicellular organisms.
Work it through
Trace water and glucose in a plant cell
- Step 1 Water can move across the selectively permeable cell membrane by osmosis, depending on relative water concentration.
- Step 2 Glucose produced through photosynthesis in chloroplasts can be used in cellular processes.
- Step 3 Mitochondria help release usable energy from glucose, while the nucleus contains genetic information that directs cell activities.
- Step 4 The cell wall supports the plant cell, and many specialized cells organize into tissues, organs, and systems that transport materials through the plant.