l, or fuse the Gaur skin cell with the enucleated egg cell B1\n- Apply an electric shock to stimulate and activate the reconstructed cell to initiate cell division B1\n- Culture the cell to allow division by mitosis to form an early-stage embryo or blastocyst B1\n- Implant the embryo into the uterus of the surrogate domestic cow to undergo gestation and birth B1","marks":5,"order":0,"markingRubric":null,"explanation":null,"options":[]}],"options":[],"explanation":null,"firstAttemptFullMarks":null},{"id":"dd936ebf-1fc8-4c7d-9c0f-a0ab573d809b","revisionId":"b6580fd1-ee7c-403d-9cf2-c745d255ffeb","questionNumber":null,"questionType":"LA","specification":"","difficulty":4,"difficultyBand":"medium","totalMarks":6,"sourceTitle":null,"calculatorUse":null,"parts":[{"id":"81bd5641-9124-4a93-8caa-702965ba25b2","label":null,"content":"Describe the stages involved in cloning a mammal, such as a dog, using somatic cell nuclear transfer (SCNT).","markscheme":"- Extract a diploid nucleus from a somatic (body) cell of the mammal to be cloned B1\n- Remove the nucleus from an unfertilised donor egg cell to produce an enucleated egg cell B1\n- Insert or fuse the diploid somatic nucleus into the enucleated egg cell B1\n- Apply an electric shock (or chemical stimulus) to stimulate division by mitosis B1\n- Allow the cells to divide and develop into an embryo *in vitro* B1\n- Implant the embryo into the uterus (womb) of a surrogate mother to develop throughout pregnancy B1","marks":6,"order":0,"markingRubric":null,"explanation":null,"options":[]}],"options":[],"explanation":null,"firstAttemptFullMarks":null},{"id":"e60bf3ea-4293-407a-bb2c-95e0d193b5f3","revisionId":"23abcbdb-0842-45ed-ae4a-b3e05e73022b","questionNumber":null,"questionType":"LA","specification":"$42","difficulty":3,"difficultyBand":"medium","totalMarks":11,"sourceTitle":null,"calculatorUse":null,"parts":[{"id":"a0a628ac-e0b1-4f64-b36b-5968d0438e2d","label":"a","content":"Name one nitrogenous base found in DNA.","markscheme":"- States any one of: adenine, thymine, cytosine, or guanine B1","marks":1,"order":0,"markingRubric":null,"explanation":null,"options":[]},{"id":"a4709970-807a-4d46-bf23-da4707aa083c","label":"b","content":"Suggest why explants are sterilised before being placed on the growth medium.","markscheme":"- To kill potential pathogens or microorganisms (such as bacteria, fungi, or viruses) on the surface of the tissue B1\n- To prevent infection of the explant or competition with microbes for nutrients on the growth medium B1","marks":2,"order":1,"markingRubric":null,"explanation":null,"options":[]},{"id":"9f3112be-2f65-4c17-8f70-55aeaf1edb42","label":"c","content":"Suggest why amino acids are provided in the growth medium.","markscheme":"- To synthesise proteins or enzymes required for growth and metabolic processes B1","marks":1,"order":2,"markingRubric":null,"explanation":null,"options":[]},{"id":"c1a9c3ce-8823-4373-bff0-f2cfe5479036","label":"d","content":"State what is meant by the term *pathogen*.","markscheme":"- A pathogen is a disease-causing organism B1","marks":1,"order":3,"markingRubric":null,"explanation":null,"options":[]},{"id":"f5922dad-52c1-4e9c-9b51-11570ababa73","label":"e","content":"Suggest two reasons why growers prefer to use micropropagation rather than sexual reproduction (growing from seeds) to produce plants for Taxol extraction.","markscheme":"- Plants produced are genetically identical clones, ensuring that high-yield Taxol production traits are retained B1\n- Allows rapid production of large quantities of plants in a compact space (or year-round production, or pathogen-free plants) B1","marks":2,"order":4,"markingRubric":null,"explanation":null,"options":[]},{"id":"4e26c5ae-fae2-4d1b-a390-162e0c59e43a","label":"f","content":"Explain what is meant by a *sustainable resource*.","markschem

Cloning

Question 27

Cloning Questions

Cloning

Question 27

Cloning Questions