Learning focus
Develop transferable AO3 skills: plan, measure, record, process, interpret and evaluate biological investigations accurately and safely.
Seed observation
Soak a dicot seed to soften the testa. Remove it carefully and separate cotyledons to expose the plumule, radicle and embryo axis. Draw only visible structures and note the relative size of cotyledons and embryo.
Flower dissection
Identify sepals, petals, anthers, filaments, stigma, style, ovary and ovules. A longitudinal section through the ovary may reveal ovules. Use a tile and safe cutting technique.
Comparative questions
Features may be used to infer insect or wind pollination. State observations first, such as exposed anthers or feathery stigma, then link them to pollen transfer only when explanation is requested.
Drawing and measurement
Use large clear line drawings and ruled labels. If magnification is requested, measure the drawing and specimen in the same unit. Counts such as petal number should be recorded exactly.
Practical or data skill
Dissect one seed and one flower. Produce a labelled drawing and a table comparing observed reproductive structures and their functions.
Examination tip
Do not add a structure simply because it appears in a textbook diagram; draw what is visible.
Review questions and suggested answers
Question 1
Why soak a seed before dissection?
Suggested answer
To soften the testa and make structures easier to separate.
Question 2
What safety precaution is needed for a flower section?
Suggested answer
Cut on a tile and away from fingers.
Question 3
What develops from an ovule after fertilisation?
Suggested answer
A seed.
