Biology • Year 12 • Module 6 • Lesson 13
Current Genetic Technologies That Induce Genetic Change
Apply the lesson’s three-category framework (reproductive, DNA-copying, DNA-inserting/cloning) to comparison data and scenarios drawn from the five named technologies in the lesson.
1. Compare the five technologies, lesson data table
The table below summarises the five current genetic technologies covered in this lesson. Use it to answer the questions that follow. 7 marks
| Technology | What changes? | Where does it act? | Why is it used? |
|---|---|---|---|
| Artificial insemination | Which sperm fertilises the egg | At reproduction in animals | Controlled breeding, spread of selected traits, reduced need to move breeding animals |
| Artificial pollination | Which pollen reaches the stigma | At reproduction in flowering plants | Controlled crosses, crop improvement, trait combination |
| Whole-organism cloning | Produces a near-genetically identical organism from a donor nucleus | Cellular and developmental level | Preserve elite traits, research |
| Gene cloning | Copies a selected DNA sequence many times | DNA and host-cell level | Analysis, protein production, vector preparation |
| Recombinant DNA / transgenics | Inserts chosen DNA into a vector or genome | DNA sequence level in cells | New trait introduction, medicine, agriculture, industrial production |
1.1 Identify the two technologies in the table that act at the level of reproduction rather than at the DNA sequence level, and state what each one changes. 2 marks
1.2 Using the table, explain one important way gene cloning differs from recombinant DNA technology in terms of what changes. 2 marks
1.3 A student claims that artificial insemination and recombinant DNA technology “both change genes because both involve biological materials.” Use the table to explain why this claim is inaccurate. 3 marks
2. Interpret a classification diagram
The diagram below places the five technologies on a spectrum from controlling reproduction (left) to directly changing DNA sequence (right). 6 marks
2.1 Describe why whole-organism cloning is placed in the middle of the spectrum rather than on the left (reproductive) or right (DNA sequence) end. 2 marks
2.2 A scientist wants to introduce a new trait into an organism that no individual in the species currently possesses. Which end of the spectrum contains the most suitable technology, and which technology would you choose? Justify using the lesson’s “what changes” column. 2 marks
2.3 The lesson warns against treating all genetic technologies as “the same thing.” Use the diagram to show why level of action matters when comparing technologies. 2 marks
3. Case studies, apply the lesson framework
Read each short case study, then answer the question that follows. Use lesson terminology (reproductive technology · DNA copying · DNA insertion · induced genetic change · transgenic organism). 9 marks
Case A, Cattle breeding program.
A cattle stud wanted to spread the milk-yield traits of one high-value bull across 500 cows in a single season. The breeding manager introduced semen collected from the selected bull into each cow, avoiding the need to transport the animal. The program ran for three years and the proportion of daughters inheriting high-yield alleles increased substantially.
3.1 Identify the genetic technology being used. Using the lesson’s “what changes, where it acts, why used” framework, explain how this technology induces genetic change at the population level, and state one advantage it offers over natural mating. 3 marks
Case B, Protein research laboratory.
A research team needed large quantities of a specific human protein to study its structure. They inserted the human gene coding for that protein into a plasmid, then introduced the plasmid into bacterial host cells. As the bacteria divided, each daughter cell contained a copy of the human gene, and after selection and culture, the team had millions of copies of the sequence available for further work.
3.2 Identify the genetic technology being used. Explain what was “induced” at the molecular level, the role of the vector in this process, and why this technology is categorised differently from artificial insemination. 3 marks
Case C, Animal research program.
Scientists wanted to study whether a particular genotype produced consistent results across multiple experiments. They took the nucleus from a body cell of a donor animal with the desired genotype, inserted it into an egg cell whose own nucleus had been removed, and stimulated development. Several animals with essentially the same nuclear genetic information as the original donor were produced over successive trials.
3.3 Identify the genetic technology being used. Using the lesson’s three distinctions (Card 4), explain why this technology does not guarantee that all resulting animals will be phenotypically identical to the donor, even though their nuclear DNA is the same. 3 marks
4. Apply, sort six technologies into the lesson categories
A Year 12 student is preparing notes for the IQ3 entry essay. Their list has six items, but they have not yet sorted them. Place each item in the correct row of the table below, and write a one-sentence justification using lesson terminology. 6 marks (1 sort + 1 justification per item)
Items to sort: artificial insemination of dairy cows · artificial pollination of wheat · gene cloning into a plasmid · inserting a gene into a host genome to produce a transgenic organism · whole-organism cloning of a research animal · recombinant DNA technology used to produce a useful protein in bacteria.
| Lesson category | Item | One-sentence justification |
|---|---|---|
| Reproductive technology (controls gamete combination) | ||
| Reproductive technology (controls gamete combination) | ||
| DNA-level, copies DNA | ||
| DNA-level, inserts DNA into a host | ||
| DNA-level, inserts DNA into a host | ||
| Cellular / developmental, preserves a genotype |
Q1.1, Reproductive technologies (2 marks)
Artificial insemination changes which sperm fertilises the egg [1]. Artificial pollination changes which pollen reaches the stigma [1]. Both act at reproduction rather than at the DNA sequence level.
Q1.2, Gene cloning vs recombinant DNA (2 marks)
Gene cloning copies a selected DNA sequence many times, producing multiple identical copies of existing DNA [1]. Recombinant DNA technology inserts chosen DNA into a vector or host genome, placing the sequence into a new cellular context and potentially allowing expression of a new trait [1]. Copying and inserting are different outcomes, so these are distinct technologies.
Q1.3, AI vs recombinant DNA (3 marks)
The claim is inaccurate [1]. Artificial insemination involves introducing semen so that sperm from a selected male fertilises an egg, the DNA sequence inside the sperm was already produced by normal meiosis and is not altered by the procedure. It acts at the level of reproduction, not DNA sequence [1]. Recombinant DNA technology directly changes the DNA present in cells by inserting chosen sequences from a vector into a host genome, this is a qualitatively different type of intervention because it can introduce sequences not previously present in that organism [1].
Q2.1, Why whole-organism cloning is in the middle (2 marks)
Whole-organism cloning does not simply control which gametes combine (reproductive end), nor does it insert or copy a specific DNA sequence in isolation (DNA sequence end) [1]. Instead, it transfers an entire donor nucleus into an enucleated egg, operating at the cellular and developmental level, it aims to copy an organism-level genotype, which is a different kind of manipulation from either controlling gamete combination or working directly with a gene sequence [1].
Q2.2, Introducing a new trait (2 marks)
The right end of the spectrum (direct DNA sequence change) is most suitable [1]. Recombinant DNA technology is the best choice because it inserts chosen DNA directly into a vector or genome, this is the only technology in the lesson capable of introducing a trait that does not already exist anywhere in that organism’s allele pool [1].
Q2.3, Level of action matters (2 marks)
The diagram shows that technologies acting at the reproductive level (AI, AP) cannot introduce new DNA sequences, while technologies acting at the DNA sequence level (gene cloning, recombinant DNA) can copy or insert sequences directly [1]. If you collapse all technologies into one category you lose the ability to predict what each can and cannot achieve, for example, artificial insemination cannot introduce a trait that is absent from the species’ gene pool, but recombinant DNA technology can [1].
Q3.1, Cattle breeding (3 marks)
The technology is artificial insemination [1]. It induces genetic change by controlling which sperm fertilises each egg across the herd, increasing the probability that offspring inherit alleles from the selected bull rather than from random natural mating, over three years, this shifts allele frequencies in the population [1]. Advantage: the selected bull’s traits can spread to 500 cows per season without transporting the animal, which would not be possible through natural mating alone [1].
Q3.2, Protein research lab (3 marks)
The technology is gene cloning [1]. What was induced: the human gene sequence was replicated many times at the DNA level inside host bacterial cells, producing multiple identical copies for research use [1]. The vector (plasmid) carried the inserted human gene into the bacterial host cell, where it replicated alongside the host genome. This is categorised differently from artificial insemination because it acts directly on DNA sequence rather than controlling which gametes combine [1].
Q3.3, Animal research program (3 marks)
The technology is whole-organism cloning (using somatic-cell nuclear transfer) [1]. The key distinction (Card 4) is that cloning aims for genetic sameness, not guaranteed identical phenotype [1]. Even when the nuclear DNA is the same, the developmental environment (uterine conditions, postnatal experience) and epigenetic patterns still vary, these can influence how genes are expressed, meaning the resulting animals may differ in coat colour, physiology or behaviour even though they share the donor’s nuclear genotype [1].
Q4, Sort six technologies (6 marks)
Reproductive technologies (1 mark each, max 2): artificial insemination of dairy cows controls which sperm fertilises each egg, acting at reproduction; artificial pollination of wheat controls which pollen reaches the stigma.
DNA-level, copies DNA (1 mark): gene cloning into a plasmid uses a vector and host cell to make many copies of a selected DNA sequence.
DNA-level, inserts DNA (1 mark each, max 2): inserting a gene to produce a transgenic organism chosen DNA is inserted into the host genome, producing an organism containing external DNA; recombinant DNA technology used to produce a protein in bacteria inserts a selected gene into a bacterial host cell so it can be expressed and a useful protein produced.
Cellular / developmental (1 mark): whole-organism cloning of a research animal transfers a donor nucleus into an enucleated egg to preserve the donor’s genotype at the organism level.
Marking notes. 1 mark per correct placement (max 6). Justifications must reference the lesson’s “what changes” language.