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Activity 9. By researching cell division, I can explain its role in growth and repair and can discuss how some cells can be used therapeutically SCN 4-13a I can debate the moral and ethical issues associated with some controversial biological procedures SCN 4-13c. http://www.eurostemcell.org.
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Activity 9 • By researching cell division, I can explain its role in growth and repair and can discuss how some cells can be used therapeutically SCN 4-13a • I can debate the moral and ethical issues associated with some controversial biological procedures SCN 4-13c http://www.eurostemcell.org
Task 1 Lesson Starter Here are the opening paragraphs from two websites introducing genetic engineering – which one is Greenpeace and which is Monsanto – a Multinational Agricultural Biotechnology Company? 1.Today, biotechnology holds out promise for consumers seeking quality, safety and taste in their food choices; for farmers seeking new methods to improve their productivity and profitability; and for governments and non-governmental public advocates seeking to stave off global hunger, assure environmental quality, preserve bio-diversity and promote health and food safety.
2. Genetic engineering enables scientists to create plants, animals and micro-organisms by manipulating genes in a way that does not occur naturally. These genetically modified organisms (GMO) can spread through nature and interbreed with natural organisms, thereby contaminating non 'GE' environments and future generations in an unforeseeable and uncontrollable way. Their release is 'genetic pollution' and is a major threat because GMOs cannot be recalled once released into the environment.
Task 2 http://www.eurostemcell.org/films/a-stem-cell-story/English (15mins)Video on IVF production of Stem Cells and Ethical Issues (4.5mins)http://www.bbc.co.uk/learningzone/clips/stem-cell-research-and-medicine/6013.html
1 stem cell Why self-renew AND differentiate? 1 stem cell 4 specialized cells Differentiation - replaces dead or damaged cells throughout your life Self renewal – makes sure stem cells don’t run out
skin muscles Stem cells in your body = Tissue stem cells surface of the eye brain breast intestines (gut) bone marrow
found in bone marrow Blood stem cells: A type of tissue stem cell blood stem cell red blood cells differentiation white blood cells only specialized types of blood cell
Why are scientists so interested in stem cells? Scientists around the world are trying to • understand how and why stem cells can self renew and differentiate. • They want to use them to help understand about human development. • Find out if they can be used to treat disease. • Use them as human stem cell models to help understand what goes wrong in cells. • Have more realistic ways to test new treatments on human cells
The challenge The big challenge for scientists is to learn how to control these fascinating cells. If we could force stem cells to make whatever kind of cell we want, then we would have a powerful tool for developing treatments for disease. Example, perhaps we could grow new pancreas cells to transplant into the pancreas of a patient with diabetes, which could then make it’s own insulin to control blood sugar levels.
skin neurons liver Embryonic stem cells One cell removed and grown in a dish in a lab embryonic stem cells blastocyst - a very early embryo (5 days) around 100-150 cells ES cells can make many kinds of specialised cells in the lab!
Induced pluripotent stem cells – iPS cells • These cells were first made in a laboratory by a scientist in 2006. • iPS cells are made by adding four special genes to a tissue stem cell and these reprogrammed the cell. What was produced was a cell that could make any cell type. Therefore it was very similar to an embryonic stem cell. • The scientist who created it thought this would help alleviate the controversial issues surrounding embryonic stem cells. http://www.eurostemcell.org/factsheet/reprogramming cells
Task 3 • Complete the Worksheet on Stem Cells using the work cards and the information that you have gathered in this lesson.
Activity 2 – ExtensionComparing Embryonic and Tissue Stem Cells
Comparing Embryonic and Tissue Stem Cells These are cells found in many areas of the body that need to be renewed throughout the life of the person. However these stem cells are already partly specialised and will only make up all the cell types of the tissue they are found in. e.g blood stem cells make all the different cells of the blood, Skin stem cells make all the different cells of the skin. It is much easier and less controversial to grow these stem cells in the laboratory and cells can be taken from a patient Why might Scientists not find these stem cells as useful as Embryonic stem cells? Or maybe they have other advantages over Embryonic stem cells?
What we’ve learnt today - Summary Stem cells can: Self-renew = copy themselves Differentiate = make other types of cell There are different kinds of stem cell: Tissue stem cells – in our bodies all our lives – only make particular cell types Embryonic stem cells – in the early embryo – can make all the cells of the body iPS cells – reprogrammed tissue stem cell – can make all cell types of the body We need stem cells to… Replace cells that die or get damaged In the future, we might use them to treat diseases or test drugs