State the cell theory and compare plant and animal cell structures, explaining how each structure supports the cell's function.
Cell theory is one of the unifying ideas of biology, built from many scientists' observations: all living things are made of one or more cells, the cell is the basic unit of structure and function in living things, and all cells come from cells that already existed. Whether you are looking at a single-celled organism or a redwood tree with trillions of cells, the same basic idea holds true.
Plant and animal cells share several structures: a cell membrane controlling what enters and exits, cytoplasm filling the interior, a nucleus holding genetic instructions, and mitochondria that release usable energy from food, sometimes nicknamed the cell's powerhouse. Plant cells add three structures animal cells lack: a rigid cell wall outside the membrane for support and protection, a large central vacuole that stores water and helps keep the cell firm, and chloroplasts that capture light energy for photosynthesis, which you will study in depth next week.
Mastery looks like: They can state cell theory accurately and correctly sort a list of structures into plant-only, animal-only, or both, with a function for each.
Common stumbles: Thinking animal cells have no structures in common with plant cells at all; forgetting that plant cells have both the shared structures AND the extra three.