Name: ________________________ B6 CLONING Practice questions Class: ________________________ Date: ________________________ Time: 108 minutes Marks: 108 marks Comments: Biology Only Page 1 of 35 The photograph shows a zorse. 1 By Kumana @ Wild Equines [CC-BY-2.0], via Wikimedia Commons A zorse is a cross between a male zebra and a female horse. The zorse has characteristics of both parents. (a) The zorse was produced by sexual reproduction. (i) What is sexual reproduction? ______________________________________________________________ ______________________________________________________________ (1) (ii) The zorse has characteristics of a zebra and a horse. Why? ______________________________________________________________ ______________________________________________________________ ______________________________________________________________ ______________________________________________________________ (2) Page 2 of 35 (b) Zorses are not able to breed. Scientists could produce more zorses from this zorse by adult cell cloning. The diagram shows how the scientists might clone a zorse. Page 3 of 35 In this question you will be assessed on using good English, organising information clearly and using specialist terms where appropriate. Use information from the diagram and your own knowledge to describe how adult cell cloning could be used to clone a zorse. ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ (6) (Total 9 marks) It is now possible to clone humans. The diagram shows one way in which this can be done. 2 (a) What type of reproduction is this? ___________________________________________________________________ (1) Page 4 of 35 (b) Will the baby have the characteristics of the egg cell or the body cell? ___________________________________________________________________ Explain the reason for your answer. ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ (2) (c) The procedure in the diagram could be used to produce several cloned embryos. Suggest how this might be done. ___________________________________________________________________ ___________________________________________________________________ (1) (Total 4 marks) 3 In some methods of reproduction, clones are made. (a) Explain what is meant by a clone. ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ (2) Page 5 of 35 (b) To gain full marks for this question you should write your ideas in good English. Put them into a sensible order and use the correct scientific words. Describe, in as much detail as you can, one way in which an embryo can be cloned. ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ (3) (Total 5 marks) As embryos develop, some genes in cells are turned off and some genes are turned on.This 4 allows cells to become specialised for particular functions. Usually, after cells have become specialised, they cannot change again into different types of cells. (a) What is a gene? ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ (2) Page 6 of 35 (b) Scientists have developed a way to change specialised cells back into embryo-like cells by a method called iPS. Read the information in the box. Cells made using iPS can be changed into different types of cells. Scientists plan to take skin cells from an endangered species of monkey called a drill and change these cells into iPS cells. These iPS cells can then be changed into egg cells or sperm cells. After fertilisation, the embryo can be inserted into the womb of a female of a non-endangered species called a mandrill. The mandrill is closely related to the drill. Describe similarities and differences between the iPS method and adult cell cloning. ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ (4) (c) Suggest one advantage of trying to preserve endangered species such as the drill. ___________________________________________________________________ ___________________________________________________________________ (1) (Total 7 marks) Page 7 of 35 Scientists have brought an extinct species of mountain goat, the Pyrenean ibex, ‘back to life’. 5 These scientists used skin cells from preserved Pyrenean ibex in cloning experiments. The Scientists: • removed the nuclei from domestic goat egg cells • transferred cell nuclei from the skin cells of the Pyrenean ibex into domestic goat egg cells • used the domestic goats as surrogate mothers for the embryos that developed. The scientists made 439 cloned embryos, but only 57 were suitable for transfer into the surrogate goat mothers. Only seven of the goats got pregnant and only one live offspring was born. Some biologists are very worried about using cloning to preserve endangered animals, because cloned animals often have developmental problems. Some endangered animals are difficult to breed in captivity. For these animals cloning is another way to continue the genetic line. The biggest threats to endangered animals today are habitat loss, illegal hunting, pollution and climate change. Many scientists say that cloning is not as important as trying to preserve the wild places on Earth. The wild places are being lost very quickly and the animals and plants living in the wild places are dying out. (a) The Pyrenean ibex was ‘brought back to life’. How is this process different from using adult cell cloning to clone a pet animal? ___________________________________________________________________ ___________________________________________________________________ (1) Page 8 of 35 (b) Evaluate the use of adult cell cloning to conserve endangered species. Use the information given and your own knowledge and understanding. Remember to give a conclusion to your evaluation. ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ (4) (Total 5 marks) Organisms can be produced by asexual reproduction and by sexual reproduction. 6 (a) Give two differences between asexual reproduction and sexual reproduction. 1. _________________________________________________________________ ___________________________________________________________________ 2. _________________________________________________________________ ___________________________________________________________________ (2) Page 9 of 35 (b) Adult cell cloning is a type of asexual reproduction. Explain why. ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________