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Cloning produces genetically very similar descendants through asexual processes. Plant cuttings and tissue culture exploit cells able to divide and differentiate. Tissue culture needs suitable nutrients, hormones and aseptic technique. Animal embryo splitting separates early cells, while somatic-cell nuclear transfer places a nucleus into an enucleated egg and stimulates development. Neither route guarantees identical phenotype because environment, development and cytoplasmic factors can differ.
Video by Cognito. The video’s own board label is retained; follow the specification reference and scope notes on this lesson for assessed content.
Viewing focus: Compare natural and artificial cloning
After watching, attempt these questions before opening the answers. You can also use the written lesson below.
After watching 1: What is removed from an egg before somatic-cell nuclear transfer?
Its nucleus. The introduced nucleus supplies the intended nuclear genome.
After watching 2: Why use aseptic technique in a fermenter?
Reduce contamination and competition. Other organisms can alter yield and safety.
What you'll be able to do
Cloning produces genetically very similar descendants through asexual processes. Plant cuttings and tissue culture exploit cells able to divide and differentiate. Tissue culture needs suitable nutrients, hormones and aseptic technique. Animal embryo splitting separates early cells, while somatic-cell nuclear transfer places a nucleus into an enucleated egg and stimulates development. Neither route guarantees identical phenotype because environment, development and cytoplasmic factors can differ.
Microorganisms can produce enzymes, foods and other useful compounds. In a fermenter, nutrient supply, temperature, pH, aeration and mixing influence growth and product formation. Sensors and feedback can regulate conditions. Asepsis reduces competition and contamination. Batch culture and continuous culture have different input and removal patterns; a growth curve can show lag, exponential, stationary and decline phases when conditions become limiting or waste accumulates. Product yield is not always maximised by maximising cell growth alone.
Immobilising an enzyme can allow separation from product, reuse and continuous processing, but can introduce diffusion limits or change operating conditions. Microbial methods offer rapid reproduction and controllable conditions, while contamination and purification remain challenges. Evaluate biological, economic and ethical implications of a particular cloning or production method. Genetic similarity can preserve a desirable trait but may reduce population resilience when the environment or disease pressure changes.
Attempt these problems on paper before opening the worked reasoning. Explain your steps as well as giving a final answer.
Common mistakes to avoid
Key takeaways
Question 1: Why does a closed batch culture eventually stop exponential growth?
The environment no longer supports a constant maximum growth rate.
Check the assessed scope and practical or mathematical requirements.
An external explanation or interactive activity to use alongside the lesson. It may include extension material.
Close the notes and answer from memory. Revisit any explanation you cannot yet reconstruct.
Test yourself
Answer a few questions, then review anything you missed.
Start with the quiz above to check the key ideas. You can also choose another topic from the practice library.