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2.2 Cloning: Gene & Whole-Animal — Test 1
Q1. Gene (molecular) cloning refers to:✓ Producing many identical copies of a specific DNA fragment
Q2. Reproductive cloning of an animal aims to produce:✓ A whole organism genetically identical to the donor
Q3. The technique used to clone Dolly the sheep was:✓ Somatic cell nuclear transfer (SCNT)
Q4. In somatic cell nuclear transfer, the recipient egg cell must first be:✓ Enucleated (its own nucleus removed)
Q5. Dolly the sheep was historically significant because she was the first mammal cloned from a(n):✓ Adult (differentiated) somatic cell
Q6. Therapeutic cloning differs from reproductive cloning in that its goal is to:✓ Produce stem cells or tissues for treatment, not a whole organism
Q7. A 'clone' is best described as a group of cells or organisms that are:✓ Genetically identical and derived from a single ancestor
Q8. The genotype (nuclear genome) of a cloned animal is determined by the:✓ Donor of the transferred nucleus
Q9. A cloned animal is not 100% genetically identical to its nuclear donor because it inherits its mitochondrial DNA from the:✓ Egg (cytoplasm donor)
Q10. The general steps of gene cloning, in order, are:✓ Isolate DNA → insert into a vector → transform a host → select and screen
Q11. Embryo splitting (artificial twinning) produces clones by:✓ Separating cells of an early embryo, each of which forms an organism
Q12. A reconstructed embryo in nuclear transfer is brought to term by implanting it into a:✓ Surrogate mother
Q13. Animal cloning has practical applications including:✓ Multiplying elite livestock and producing pharmaceutical proteins
Q14. A major practical limitation of reproductive cloning by SCNT is its:✓ Low efficiency and high rate of developmental abnormalities
Q15. Recombinant DNA cloning (gene cloning) and reproductive cloning differ chiefly in that gene cloning copies:✓ A DNA fragment, while reproductive cloning copies a whole organism
Q16. The ability of an early embryonic cell to give rise to a complete organism is called:✓ Totipotency
Q17. In nuclear transfer, the donor somatic nucleus must be 'reprogrammed' so that it:✓ Behaves like an embryonic nucleus and supports development
Q18. Patient-specific stem cells generated by therapeutic cloning are valuable because they are:✓ Genetically matched to the patient, reducing immune rejection
Q19. Which sequence correctly distinguishes the cell used as the nuclear donor versus the recipient in SCNT?✓ Donor = somatic cell; recipient = enucleated egg
Q20. Match each cloning term with its meaning and select the correct option.✓ A-ii, B-iv, C-i, D-iii