Coordination, Defense & Reproduction — Investigation · Life Science & Scientific Inquiry, Grade 7
Five focused units, a three-session investigation, chapter review, and chapter quiz.
Compare seed germination
Investigate
How does a defined treatment affect germination in the supplied comparison?
Materials
- Supplied independent-group data and notebook
- Optional suitable seeds, clean water, containers, and paper for an adult-approved observation
Before you begin
The core uses data. For an optional germination activity use known suitable seeds, do not eat experimental seeds, and do not open or handle moldy samples. No bodily or infection testing is involved.
Plan a fair test
Change the defined water treatment. Keep species, seed count, interval, temperature, and germination definition comparable; each row is an independent group.
Method
- Define germination and the seven-day interval.
- Plan comparable groups and record all seeds, including those not germinated.
- Calculate each group’s percentage and pooled success in each treatment.
- Distinguish pollination, fertilization, germination, and later survival.
- Explain the pattern and revise a claim about every species or lifelong success.
Illustrative course data — use for analysis without equipment
Illustrative records: these are invented teaching data, not published measurements or the learner’s own observations. Actual measurements may differ; record them separately if you perform an optional suitable activity.
| Independent group | A germinated /20 | B germinated /20 |
|---|---|---|
| 1 | 18 | 12 |
| 2 | 17 | 13 |
| 3 | 19 | 11 |
Analyze and explain
- What are the pooled percentages?
- Why include all tested seeds?
- What does the study not tell us about adults?
What a strong explanation includes
- Explain the relevant biological process accurately.
- Use the supplied evidence and show calculation steps with units where needed.
- Connect a labeled model or mechanism with the claim.
- State an assumption, evidence limitation, or useful next observation.
Parent / teacher guide: discuss after the investigation
A totals 54 of 60 seeds, or 90%, and B 36 of 60, or 60%. The pooled difference is 30 percentage points. The comparison concerns seven-day germination under the stipulated water treatments, not universal species response or adult survival. Replicate conditions, avoid excluding failed seeds, and measure later outcomes separately. Seed resources can support early growth before mature photosynthetic leaves.
Compare this model with the learner’s actual evidence. Different measurements can support a different conclusion; check the reasoning and limitations, not matching wording.