Water climbs a paper fiber and beads on a waxed surface even though gravity acts on both.
Learning target
Build an initial model and explanation for: Why do a few chemical properties make water and carbon so important to living systems?
Evidence task
Record observations, questions, an initial model, and one claim that could be tested. Use these concepts where relevant: polarity; hydrogen bonding; cohesion; adhesion; carbon skeletons.
Compare ratios and percent composition in simple biomolecule data.
Evidence task
Show units, setup, calculation or graph reasoning, then write what the quantitative evidence can and cannot establish about: Why do a few chemical properties make water and carbon so important to living systems?
Safe capillary-action or surface-tension investigation using water only.
Safety boundary
Use the course safety charter. If supervision, facilities, materials, or conditions are not appropriate, use the supplied-data/simulation alternative rather than improvising hazardous procedures.
Evidence task
Record variables or design constraints, procedure/model, observations/data, and one revision you would make after reviewing the evidence.
Answer the essential question: Why do a few chemical properties make water and carbon so important to living systems?
Mastery evidence
Submit a claim, at least two specific pieces of evidence, reasoning that connects them, one limitation/counterclaim, and a correction note for any essential concept below 80%.
Portfolio
Select one artifact from this week and explain why it is trustworthy evidence of growth.