Biology: Genetic Engineering: How Scientists Modify DNA
Exploring DNA, genes, tools, and ethical choices
Biology: Genetic Engineering: How Scientists Modify DNA
Exploring DNA, genes, tools, and ethical choices
Biology - Grade 6-8
- 1
In your own words, explain what genetic engineering means.
Think about DNA as instructions that cells use.
Genetic engineering means changing an organism's DNA on purpose to add, remove, or change a trait. - 2
DNA is often compared to a set of instructions. Explain why this comparison is useful.
The comparison is useful because DNA contains the instructions for making proteins, and proteins help determine an organism's traits. - 3
A gene is a section of DNA. What does a gene usually contain instructions for?
Genes are smaller parts of chromosomes.
A gene usually contains instructions for making a specific protein or functional molecule that affects a trait. - 4
Scientists can use restriction enzymes to cut DNA. What is the job of a restriction enzyme in genetic engineering?
A restriction enzyme cuts DNA at specific sequences, which helps scientists remove or insert pieces of DNA. - 5
What is a plasmid, and why are plasmids useful in genetic engineering with bacteria?
Plasmids can act like delivery vehicles for DNA.
A plasmid is a small circular piece of DNA often found in bacteria. Plasmids are useful because they can carry a new gene into a bacterial cell. - 6
Put these steps in a logical order for making bacteria produce human insulin: insert the insulin gene into a plasmid, grow the modified bacteria, cut open the plasmid, isolate the human insulin gene, collect the insulin protein.
The logical order is to isolate the human insulin gene, cut open the plasmid, insert the insulin gene into the plasmid, grow the modified bacteria, and collect the insulin protein. - 7
CRISPR is a gene editing tool. What can CRISPR help scientists do to DNA?
CRISPR works like a guided cutting tool.
CRISPR can help scientists find a specific DNA sequence and cut it so a gene can be changed, removed, or repaired. - 8
Explain the difference between adding a new gene and turning off an existing gene.
Adding a new gene gives an organism new DNA instructions, while turning off an existing gene stops or reduces the use of instructions that are already in the organism's DNA. - 9
A crop plant is engineered to resist an insect pest. Name one possible benefit and one possible concern.
Think about both farming and ecosystems.
One possible benefit is that farmers may lose fewer crops to insects. One possible concern is that the engineered trait could affect other insects or spread to wild plants. - 10
Why do scientists test genetically engineered organisms before using them widely?
Scientists test genetically engineered organisms to check whether the DNA change works correctly and whether the organism is safe for people, other organisms, and the environment. - 11
Some bacteria are engineered to make medicine. Explain why bacteria are useful for this purpose.
Think about how fast bacteria reproduce.
Bacteria are useful because they grow quickly, are easy to study in labs, and can use inserted genes to make useful proteins such as medicines. - 12
Look at a simple genetic engineering diagram with these labels: donor DNA, plasmid, modified plasmid, bacterial cell, and protein product. Describe what happens from the donor DNA to the protein product.
A useful gene is taken from the donor DNA and inserted into a plasmid. The modified plasmid enters a bacterial cell, and the bacterium uses the gene instructions to make the protein product. - 13
Why is it important for scientists to know the exact DNA sequence before editing a gene?
A small change in the wrong place can matter.
It is important because scientists need to target the correct location in the DNA and avoid changing the wrong gene or causing an unwanted effect. - 14
A scientist edits a gene in a body cell of one animal. Will that DNA change automatically be passed to the animal's offspring? Explain your answer.
Body cells and reproductive cells are different.
No, the change will not automatically be passed to the offspring because changes in body cells are usually not inherited. DNA changes must be in egg or sperm cells to be passed on. - 15
Write one ethical question people should discuss before using genetic engineering in humans.
One ethical question is whether it is fair and safe to edit human DNA, especially if the change could affect future generations.