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1.2 The ‘genes and behaviour’ problem

Amidst the progressive change to the brain and nervous system that occurs during development, there is one constant, one fixed element; the set of deoxyribonucleic acid, DNA, molecules found in each cell. These molecules are the genetic material, and they store the information for the construction of the organism. The same set of DNA molecules is found in every cell of an organism (its genome). (There are some exceptions to this such as sperm, unfertilised egg and red blood cells, but they ne
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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
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1.7.2 How enzymes work

Enzyme molecules have an ‘active site’ that is a specific shape for a given enzyme. It is here that reactant molecules are converted into products. The active site binds to and holds the reactant molecule in exactly the right position for the reaction to take place. Effectively it fits around the molecule rather like a glove fits around a hand. This very precise three-dimensional structure can only be achieved by enzymes being large complex molecules.

Because the enzyme fits the re
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1.2.3 The transmission of genetic material

The full complement of 46 chromosomes in the human genome, the diploid number, is restored at fertilization. As Figure 3.1 shows, all the somatic cells and cells in the testes and ovaries arise from the same fertilized egg by the process of mitosis; the cells all contain copies of the same genetic material (with some exceptions).

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1.3 Different models of PhDs within and across disciplines

There are many different models of how a PhD might be conducted. The models are shaped by the expected place of study (e.g. on the OU campus, in an industry laboratory, at the kitchen table), by the intensity of study and focus (e.g. full time, part time), by the number of influences on the research (e.g. student directed, part of a larger research project, part of an industry research programme), by the level of intended guidance (e.g. taught introduction, supervision-as-collaboration, large
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Acknowledgements

The content acknowledged below is Proprietary (see terms and conditions) and is used under licence.

Grateful acknowledgement is made to the following sources for permission to reproduce material in this unit:

The content acknowledged below is Proprietary and is used under licence.

Figures

Figure 1 IPR/15-22, reproduced b permission of the British Geological Survey. © NERC. All rights reserved;

Figure 10 & 16 Courtesy
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1.9.1 Moving around the rock cycle

One way of illustrating the possible ways of moving material around the rock cycle is to draw a diagram that places the processes into their geological contexts. Since the rock cycle involves processes occurring on the Earth's surface and also within its interior, we use a cross-section through the Earth's crust and uppermost mantle to do this, as shown in Author(s): The Open University

1.8.2 Interpretation of a geological exposure

We now want to make use of the observations obtained by sketching the exposure, and it is useful to start by briefly summarising the features seen. First of all, you probably noticed the large boulder in the foreground of Figure 16 (which has been attached below for ease of access). Where did this boul
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1.8.1 Making and using field sketches

How do we start to make sense of a rock exposure? Drawing a sketch is one of the best ways to start, as it forces you to notice many aspects of the exposure. It also helps you to build up a picture of which aspects are significant and which are incidental or even irrelevant to a geological study. The aim of a field sketch is that it provides a record of your observations (along with notes taken at the same time, and also perhaps a photograph to record details). A sketch is complementary to a
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1.8 Geological fieldwork

Although much can be learned from samples of rocks in the laboratory or at home, the ‘natural habitat’ of rocks is outdoors. Here the distribution and layout of different rocks is visible wherever rocks are exposed in places such as stream beds, cliffs, rocky shorelines, quarries, or road cuttings. The exposed rocks can be studied in just the same detail as individual laboratory samples, and geological fieldwork allows the size and extent of each rock unit to be seen and the relationships
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1.4 Reflecting telescopes

A lens is not the only object that can collect and focus light and thus produce visual images. People have known about and used mirrors for much of recorded history, but it took no less a genius than Isaac Newton to realise how a curved mirror could be used to construct an optical telescope, and that this would overcome some of the most important shortcomings of refracting telescopes.

As noted earlier, a concave spherical mirror will reflect parallel rays approaching along its ax
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References

Baker, J. M. R. (1992) Body condition and tail height in great crested newts, Triturus cristatus, Animal Behaviour, 43, pp. 157–159.
Bronson, F. H. (1987) Environmental regulation of reproduction in rodents. In: Psychobiology of Reproductive Behavior, D. Crews (ed.), Prentice Hall, New Jersey. p. 209.
Hedenstrom, A. and Alerstam, T. (1992) Climbing perfo
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1.8 Primordial nucleosynthesis

Time: 100 s to 1000 s

Temperature: 109 K to 3 × 108 K

Energy: 300 keV to 100 keV

As the temperature continued to decrease, protons and neutrons were able to combine to make light nuclei. This marked the beginning of the period referred to as the era of primordial nucleosynthesis (which literally means ‘making nuclei’). The first such reaction to become energetically favoured was that of a single proton and neutron comb
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6: Summary

All objects, irrespective of their mass, experience the same acceleration g when falling freely under the influence of gravity at the same point on the Earth. Close to the Earth's surface, g=9.8 m s−2. The weight of an object is the force F g due to gravity acting on the object, and for an object with mass m the weight is given by F g=mg.

If the height of an object of mass m changes by Δh, the ch
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Learning outcomes

At the end of this unit you should know that:

  • By biological evolution we mean that many of the organisms that inhabit the Earth today are different from those that inhabited it in the past.

  • Natural selection is one of several processes that can bring about evolution, although it can also promote stability rather than change.

  • The four propositions underlying Darwin's theory of evolution through natural selection are: (1) more individuals are produced
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Introduction

In this unit, we describe the theory of evolution by natural selection as proposed by Charles Darwin in his book, first published in 1859, On The Origin of Species by Means of Natural Selection, or The Preservation of Favoured Races in the Struggle for Life. We will look at natural selection as Darwin did, taking inheritance for granted, but ignoring the mechanisms underlying it.

This unit is from our archive and is an adapted extracted from Discovering science (S103) whic
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1.5.2 Ways of organizing yourself

How do you organize yourself?

Activity

Make a note of how you organise your:

  • emails

  • internet bookmarks or favorites

  • computer files

  • your h
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1.4.1 PROMPT

There is so much information available on the Internet on every topic imaginable. But how do you know if it is any good? And if you find a lot more information than you really need, how do you decide what to keep and who to discard?

In this section we are going to introduce a simple checklist to help you to judge the quality of the information you find. Before we do this, spend a few minutes thinking about what is meant by information quality.

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1.3.8 News sources

Many news sources are now available online. Searching an online version of a newspaper is easier, quicker and more effective than searching through printed indexes, microfilm or actual newspapers.

EurekAlert! A global gateway dealing with news and links to information in the fields
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1.1.5 Organising Information

How confident are you that you know when it is appropriate to cite references (refer to the work of other people) in your written work?

  • 5 - Very confident

  • 4 - Confident

  • 3 - Fairly confident

  • 2 - Not very confident

  • 1 - Not confident at all

How confident do you feel about producing bibliographies (lists of references) in an appropriate format to accompany your written
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