• Quick retrieval from earlier learning (DNA, genes and chromosomes). Students answer on mini whiteboards.
• Show answers together and note who needs support in the main task.

1. Rosalind Franklin's X-ray image helped scientists discover… (the first vaccine / penicillin / the structure of DNA / the shape of the Earth) → the structure of DNAPrompt: Watson and Crick used her data.
2. Human body cells have 23 pairs of chromosomes. How many chromosomes are in a skin cell? → 46Prompt: Is this a gamete (sex cell) or a body cell?
3. How many chromosomes are in a normal human body cell? (92 / 12 / 23 / 46 (23 pairs)) → 46 (23 pairs)Prompt: They come in pairs, one of each pair from each parent.

• Show a microscope image of cells and ask what students think they are looking at.
• Share the objective: From gene to protein: transcription and translation. Read the success criteria together.

• Work through the example out loud, saying why you do each step, not just what you do.
• Example: Why is an mRNA copy needed? DNA could be used directly…
• Step 1: mRNA is small enough to pass through pores in the nuclear membrane.
• Step 2: So the answer is: DNA is too large to leave the nucleus, so a smaller copy carries the code to the ribosome
• Answer: DNA is too large to leave the nucleus, so a smaller copy carries the code to the ribosome
• Pause after each step and ask a student to say what comes next.

• Do these together. Students try each step on whiteboards before you reveal it.
• Use the hints as prompts rather than giving the answer.

1. Why does the final shape of a protein matter? (Shape does not matter / Shape decides the colour of the cell / Its shape lets it do its job, such as an enzyme's active site / All proteins have the same shape) → Its shape lets it do its job, such as an enzyme's active sitePrompt: Think about enzymes and antibodies.
2. Protein synthesis: which statement is NOT true? (Transcription happens in the nucleus. / A gene is a section of DNA that codes for a protein. / The order of bases decides the order of amino acids. / Each base codes for one amino acid.) → Each base codes for one amino acid.Prompt: Does DNA ever leave the nucleus?

• Students work on the student sheet. Circulate and check the first two answers of every student early.
• Students who finish: write a question of their own for a partner, with the answer.

The 5 questions are on the student sheet below, with answers in the key.

• Two questions on their own. Sort answers into got it / nearly / not yet to plan the next lesson.

1. Protein synthesis: which statement is NOT true? (A gene is a section of DNA that codes for a protein. / Each base codes for one amino acid. / Translation happens at ribosomes. / The order of bases decides the order of amino acids.) → Each base codes for one amino acid.Prompt: Does DNA ever leave the nucleus?
2. Where does translation take place? (at ribosomes in the cytoplasm / in the cell membrane / in the mitochondria / inside the nucleus) → at ribosomes in the cytoplasmPrompt: Translation builds the protein.

Free online practice with hints and printable worksheets for this skill: eurekami.com/science/grade-10.