ask what causes the on the constancy of conditions tip, point out the plants to look different. in which the seedlings are following features: Explain that the variation kept. If they vary, discuss with root cap we see is due to different students possible reasons for meristem types and arrangements this. zone of elongation of cells in each type of plant. Equipment: Tray of at least zone of 40 seedlings (fast growing, differentiation: e.g. mustard, cress or Note that the cells begin brassica) grown on a to look different in damp absorbent surface such terms of size across the as paper towel or capillary root, as cells in some matting, blunt forceps, balance areas elongate faster accurate to 0.01 g, beaker of than others. However, tap water for rinsing seedlings, true differentiation sheet of paper towel, petri dish occurs when cells base or lid or other shallow develop special features container, water for watering that are related to seedlings. particular functions. Ask the students questions as appropriate, such as: what do the cells look like in the meristem, and why are they like that? what causes the root to get longer? which kinds of specialised cells are
ask what causes the plants to look different. Explain that the variation we see is due to different types and arrangements of cells in each type of plant. on the constancy of conditions in which the seedlings are kept. If they vary, discuss with students possible reasons for this. Equipment: Tray of at least 40 seedlings (fast growing, e.g. mustard, cress or brassica) grown on a damp absorbent surface such as paper towel or capillary matting, blunt forceps, balance accurate to 0.01 g, beaker of tap water for rinsing seedlings, sheet of paper towel, petri dish base or lid or other shallow container, water for watering seedlings. tip, point out the following features: root cap meristem zone of elongation zone of differentiation: Note that the cells begin to look different in terms of size across the root, as cells in some areas elongate faster than others. However, true differentiation occurs when cells develop special features that are related to particular functions. Ask the students questions as appropriate, such as: what do the cells look like in the meristem, and why are they like that? what causes the root to get longer? which kinds of specialised cells are
GCSE-9-1-Science-Term-2-detailed-planning-document.docx