Introduction Both vitamins and minerals are essential in the diet in small quantities.The term ‘vitamin’ was not coined until early in the 20th century, to describe those chemicals in food without which a pattern of deficiency symptoms (often called a deficiency syndrome) occurs. Minerals, also called mineral elements, are those elements other than carbon, hydrogen, oxygen and nitrogen that are found in the body. This unit looks at the two main groups of vitamins: the fat-soluble vitamins A, D,
Acknowledgements Except for third party materials and otherwise stated (see terms and conditions), this content is made available under a Creative Commons Attribution-NonCommercial-ShareAlike 2.0 Licence All other materials included in this unit are derived from content originated at the Open University. 1. Join the 200,000 studen
9 Summary In this unit you have found out that: The sensation of pain is caused by the release of a chemical (prostaglandin) that stimulates the nerve endings and sends an electrical message to the brain. Pain can be reduced if the formation of prostaglandin can be inhibited. Prostaglandin is formed, from arachidonic acid, in a cavity in the active site of the enzyme cyclooxygenase (COX). Geometrical isomerism
1.8 Enter aspirin! Aspirin is able to release part of its ester group (Figure 15) in a hydrolysis reaction. Look again at the structure of aspirin, 2.8, and identify this group on the molecule. It is known as an acetyl group and accounts for aspirin also being called acetylsalicylic acid. The acetyl group on aspirin is fairly easily removed and can be available for forming another ester with an —OH group on another molecule; in this case, part of the structure that makes up the inside of the cavi
1.2.1 The human genome: chromosomes and genes Almost all of the different types of cell in an individual contain the same genetic material in the chromosomes, as a consequence of mitosis. You had a glimpse of the appearance of the 46 human chromosomes in Figure 1.1, and in this unit we examine their size, shape and genetic composition. Chromosomes can be regarded as strings of genes arranged along their length, rather like beads on a thread. Each gene consists of a short section of the DNA that runs the full length of each chromoso
Learning outcomes After studying this unit you should understand: that genes are the units of inheritance for individual characteristics and also may contribute to susceptibility to certain diseases; the number of chromosomes that make up the human genome and where they are located within the cell; something of the immense scale of the human genome project; how gametes are produced by the process of meiosis and how the full complement of 46 chromosomes
1.7.1 Research methods in context Any established discipline has a tradition of practice. Many disciplines have established methodologies which prescribe the selection, combination and sequencing of the methods and techniques to be employed. Others select methods and techniques less prescriptively and borrow more broadly across domain boundaries. All disciplines require an appropriate application of methods, in order to ensure rigour. Hence, one key skill is the demonstration of an appropriate knowledge and competence
2.4 Other spectrographs Although the simple, single-slit spectrograph described above is the type you are most likely to find on a small telescope, there are other more complex designs available. Each of these has its own role to play in astronomical observations. An echelle spectrograph has a second dispersing element, either a second grating or a prism, which disperses the light at right angles to the direction of dispersion produced by the main grating. Without going into details, the effect is to pr
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4.2 Earthquake magnitude The magnitude of an earthquake is a measure of the amount of seismic energy released by it, so it is a quantitative scale. The scale of earthquake magnitude is called the Richter scale. Its development is described in Box 4, Charles Richter and the Richter earthquake magnitude scale. The Richter magnitude
1.3.2 Search Engines and Subject Gateways Although both search engines and subject gateways will help you find the resources that you need, the types of information that you find will differ. Search engines such as Google and Yahoo! search the internet for keywords or phrases, and then show you the results. These results are not mediated by the search engines, and therefore you need to use your own judgement on the reliability of the results. You may, for example, find websites written by experts, alongside websites written by
1.3.1 Introduction You can find a lot of information about science and nature on the internet. To find this information you might choose to use: search engines and subject gateways; books and electronic books; databases; journals; encyclopedias. news sources internet resources
References 4.13.3 Scrutiny Again, connected to the accountability issue is the problem of adequate scrutiny. The detailed, technical and specific nature of much-delegated legislation means that, on the whole, Members of Parliament (the elected representatives) do not have the expertise to consider proposed legislation effectively. In addition, you have already noted that the scrutiny committees themselves only have limited powers. 1.2 Balancing the right to privacy and other rights Article 10 of the European Convention on Human Rights protects freedom of expression. Section 12 of the Human Rights Act 1998 requires the courts in the UK to have particular regard to the importance of the right to freedom of expression. However, freedom of expression and the right to privacy frequently collide. This can be illustrated by reference to the American case of Anonsen v Donohue (1993). In this case a woman revealed on national television that her husband had raped and impr 5.3.2 Directives A directive is a Community act which ‘shall be binding, as to the result to be achieved, upon each Member State to which it is addressed, but shall leave to the national authorities the choice of form and methods’. A directive therefore has to be implemented by each EU member state through its own domestic legislative process. After the enactment of a directive, the EU member states will generally be given a period of time within which to bring their domestic law in line with the objectiv 6.1 Introduction In this part we will explore the number of rules developed by the courts to assist with the interpretation of a statute. These are: the literal rule the golden rule the mischief rule the purposive approach. These rules each take different approaches to interpretation of a statute. Some judges prefer one rule, while other judges prefer another. Some judges also feel that their role is 5.2 Summary of Part D Part D explored several of the reasons which may result in a word or phrase in an Act of Parliament having an unclear meaning. This was illustrated by a number of examples. Interpretation of those words or phrases becomes a task for the courts. In this role, it can be argued that the courts are involved in the law-making process as they have been required to interpret and define a statute. 3.4.2 Distinguishing In comparison with the mechanism of overruling, which is rarely used, the main device for avoiding binding precedent is that of distinguishing. As has been previously stated, the ratio decidendi of any case is based upon the material facts of the case. This opens up the possibility that a court may regard the facts of the case before it as significantly different from the facts of a cited precedent, so it will not find itself bound to follow that precedent. Judges use the device of dis 3.3.1 Try some yourself 1 A friend has been quoted a price of £25.50 per square yard for tarmac surfacing of his yard. The yard measures 6 yards by 10 feet. Here is his calculation of the total cost. What is wrong with it? cost = £25.50 × 6 × 10 = £1530
