Here's an example of what's due today

Recombinant DNA flow

Tue, Dec 1, 2026 · Week 15 · Genetics of Disease (Medical Interventions)

Today's goal: Trace how recombinant DNA lets cells manufacture a useful human protein.

Learn first

What a finished product looks like

This is a model of the work you should turn in today. Use it to check your own: match the structure and the level of detail, do not copy it. Your data and wording should be your own.

Recombinant DNA flow diagram

Completes: Completes the recombinant-DNA flow diagram: a labeled sequence showing a plasmid cut open, a human gene inserted, a host cell transformed, and the named human protein produced.

Labeled recombinant-DNA flow (insulin example):

Step 1, Isolate the gene: Cut the human insulin gene out of human DNA using a restriction enzyme such as EcoRI, which leaves sticky ends.
Step 2, Cut the plasmid: Use the SAME restriction enzyme to open the bacterial plasmid, so its sticky ends match the gene's sticky ends.
Step 3, Insert the gene: DNA ligase seals the human insulin gene into the plasmid. The result is recombinant DNA, meaning DNA combined from two sources.
Step 4, Transform the host: Take up the recombinant plasmid into a host cell such as E. coli. The transformed bacterium now carries the human gene.
Step 5, Manufacture the protein: The bacterium reads the inserted gene using the same genetic code all cells share, transcribes it to mRNA, and translates it into human insulin protein. Grow the culture and the bacteria make insulin in bulk.

Named product: human insulin (used to treat diabetes).

Why a bacterium can read a human gene: the genetic code is nearly universal, so the codons in the human gene mean the same amino acids inside the bacterial cell.

(Tip: label the restriction enzyme as the same tool in Step 1 and Step 2, since matching sticky ends is the part graders look for.)

Why this matters

This model shows the level of evidence and organization needed to complete: Completes the recombinant-DNA flow diagram: a labeled sequence showing a plasmid cut open, a human gene inserted, a host cell transformed, and the named human protein produced.

Build yours step by step

Date and label the entry.
Record the procedure, observation, or design decision clearly.
End with what the evidence means and the next step.

Change it for a new task

Keep the structure. Replace the question, facts, measurements, and evidence. Then recheck units, vocabulary, and whether the conclusion goes beyond the evidence.

Also due today: Attach the diagram to your PLTW tracker, and turn it in on Schoology under the Unit 4 Recombinant DNA Flow assignment.

Turn in: Recombinant DNA flow diagram

Go to Schoology to turn this in.

Submit one PDF. Put your first and last name in the document header. Name the file: FirstName LastName - Assignment Title - YYYY-MM-DD.pdf.

Open Schoology PDF upload help

If you cannot get in, see Mr. Mendoza. Do not skip the work.

Claim ceiling: Today's evidence supports a classroom claim about recombinant DNA flow. It cannot prove causation, diagnose a real patient, or justify action outside this room.

Check yourself

WebXam problem for today's skill

One exam-style question that uses exactly what you practiced today. Try it before you reveal the answer, then read why each choice is right or wrong.

WebXam-style domain: Molecular and Genetic TechnologySelf-check skill: Sequencing the steps of making recombinant DNA

In a recombinant DNA procedure to make human insulin in bacteria, why is the SAME restriction enzyme used to cut both the human DNA and the bacterial plasmid?

Tap an answer to see the full explanation. Nothing is recorded or graded.

Why this practice matters

It builds this reusable test skill: Sequencing the steps of making recombinant DNA.

Use it on a new WebXam question

Name the concept or data pattern being tested.
Cross out choices that violate that rule or the evidence.
Justify the best remaining choice before checking the answer.

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