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References

Durant, J., Bauer, M., Gaskell, G., Midden, C., Liakopoulos, M. and Scholten, L. (2000) ‘Two cultures of public understanding of science andtechnology in Europe’ in Dierkes, M. and Von Grote, C. (eds) Between Understanding and Trust: the Public, Science and Technology, Amsterdam: Harwood Academic Publishers.
Eurobarometer
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4.3 Phenotypic changes that appeared without being selected

As well as these behavioural changes, many of the selected foxes had unusual white markings (Figures 13c and d). The first colour change that the Russian investigators noted in their foxes was a white ‘star’ on the forehead similar to that of other domesticated mammals (Author(s): The Open University

2 Inside the Sun

To account for its brightness and activity, the Sun must contain a power source. However, the nature of that power source was a great puzzle in the nineteenth and early twentieth centuries. Fossil records and ideas about evolution were beginning to provide firm evidence that the Earth must be at least hundreds of millions of years old, rather than thousands of years as was previously thought, and the Sun must be at least as old as the Earth. The only fuels known at the time were coal, wood, o
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2.5 Tree squirrels

Coevolution also underpins the relationship between many tree squirrels and the trees that house them. The creation of food caches as a ‘winter-larder’ is mutually beneficial, partly because squirrels are sufficiently profligate in their habits to ensure that many stores are overlooked. Stealing by neighbours is so common that such over-provision may be essential – it's not through forgetfulness or lack of skill; grey squirrels appear able to detect nuts buried as deep as 30 cm below th
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2.2 Feeding techniques

In Activity 1, below, you are asked to make notes from a TV sequence and then select some of the information from your notes and combine it
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2.1 Mammalian dentition

Insects are generally very small animals. Many kinds are hard work to collect and not very nutritious because a high proportion of their mass is a protective and indigestible outer layer, called cuticle. Insectivorous mammals need to eat large numbers of insects to fulfil their energy requirements.

Insect eaters have diverse ways of catching and dealing with their prey; teeth play a crucial role. Indeed, teeth are of such enormous significance to mammalian diets in general (and are so r
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Introduction

This unit is an introduction to chemistry concepts, using water as the main illustration. Much of the unit is devoted to exploring the smallest water particle – a water molecule – what it is and how it gives rise to the particular properties of water. The unit also explains powers of ten and scientific notation, which are a convenient way of expressing both very large and very small numbers. It is a good introduction to science.

This unit is an adapted extract from the course
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Learning outcomes

By the end of this unit you should be able to:

  • define and use, or recognise definitions and applications of, each of the bold terms;

  • provide examples that show there is a continuum of desert climates and environments that link to diversity of flora and fauna;

  • explain, with examples, the thermoregulatory strategies of evaders, evaporators and endurers, and interpret relevant data;

  • describe the importance of integration of behavi
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3.4.2 Periodic arousal

All mammalian hibernators arouse periodically. The frequency of the arousal and the length of the euthermic periods between bouts of hibernation vary widely with species, among individuals, and with the time of year (e.g. in deep hibernators, the larger species seem to have longer periods of wakefulness than the smaller ones). The arctic marmot (Marmosa caligata), whose heart rate recording is shown in Author(s): The Open University

Learning outcomes

Having read this unit you should be able to:

  • discuss how the gas mixture expelled from the engine, and the conversion performance of the three-way catalytic converter, depend on the air/fuel (A/F) ratio;

  • list the chemical reactions whereby the three-way catalyst removes carbon monoxide (CO), hydrocarbons and oxides of nitrogen (NOx) from petrol vehicle exhausts;

  • interpret the results of experimental studies (involving activity test
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3.5 Summary of Section 3

The developing organism is nudged onto different developmental paths by the environment in which it finds itself. Thus the experience of being premature, or of experiencing only horizontal visual stimuli, or of experiencing testosterone affects the kind of individual the organism becomes. And the effect of the environmental factors is both profound and enduring; the individual will, quite literally, never be the same again.


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3.6.6 Vitamin B12 (cobalamin)

Vitamin B12 is yet another group of compounds, this time with an atom of the metal called cobalt (present in only trace quantities in the body) in their structure, hence the alternative name ‘cobalamin’. Vitamin B12 works alongside folate and if levels of it are low, folate deficiency symptoms occur too. It is stored in the liver and in general the body does not appear to need a regular intake. Many people have enough B12 stored in their liver to last for
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3.6.5 Folate (folic acid, vitamin B9)

Folate is a generic name for a group of related compounds. The name ‘folate’ was based on the word ‘foliage’, after it was identified in a crude extract from spinach, though it is also found in liver, other green vegetables, oranges and potatoes and it is often added to breakfast cereals (usually listed as folic acid). Folate is less sensitive to heat than many of the B vitamins, though it is destroyed if food is reheated or kept hot for long periods. Folate is involved in amino acid
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3.6.3 Niacin (vitamin B3)

Niacin, which comprises two compounds, nicotinic acid and nicotinamide, also occurs widely in food and is added to many breakfast cereals. It is easily absorbed into the blood from the digestive system and plays a vital role in energy production in cells. It appears to reduce the levels of low density lipoproteins or LDLs in the blood and increase high density lipoproteins or HDLs, perhaps by affecting the proteins that carry the fats. This is important because LDLs are a way of transporting
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3.4 Vitamin E

Vitamin E is not a single compound, but consists of a group of eight closely related chemicals, of which the most important, responsible for about 90% of its activity in the body is alpha-tocopherol. Since, like vitamins A and D, vitamin E is fat-soluble, it occurs in fat-rich foods. The main sources in the UK diet are from plant oils such as soya, corn and olive oil. Other good sources include nuts and seeds, and wheatgerm (the part of the wheat grain that will develop into the new plant) an
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1.1 Introduction to vitamins and why we need them

Before the 19th century, one of the hazards of long sea voyages was a condition called scurvy, whose symptoms were loss of hair and teeth, bleeding gums, very slow healing of wounds, and eventually death. Hundreds of sailors and explorers died from scurvy until a Scottish physician, James Lind, in the 1750s discovered that adding a daily portion of citrus fruit to the rations of those at sea could prevent the condition, whereas adding cider, vinegar or various other substances that he tested,
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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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1.2 How does it hurt?

This is a useful question because once we know the mechanism of pain sensation we can do something about alleviating it.

When tissue is injured there follows a rapid release of ‘messenger’ chemicals that stimulate the nerve endings. Electrical impulses are relayed through the nerves to the spinal column and to the brain, which registers the sensation of pain. It usually, but not always, also directs our attention to the site where the damaged tissue initiated the pain message.


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Introduction

In this unit you will find out that the sensation of pain is caused by the release of a chemical called prostaglandin that stimulates the nerve endings and sends an electrical message to the brain. Inhibiting the formation of prostaglandin reduces pain and we will see, by looking at the specific shape of the molecules involved, how aspirin can so inhibit the formation of prostaglandin. To make the most of the material of this unit you will need to use an organic molecular modelling kit such a
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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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