Simple rules for dealing with orders of magnitude and decimal points in decimal numbers: values ten times bigger than the order of magnitude you are looking at go to the left, ten times smaller go to the right, and less than 1 to the right of the decimal point.

Note: in many European countries, a comma is used instead of a decimal point. For instance in France and Germany two and a half (in other words 2.5) can be written as 2,5. This is important to bear in mind, for example, if
Author(s): The Open University

Suppose you have less than one of any particular unit: how would you represent that using the decimal system?

Well, we've already seen that decimal numbers rely on a positional system, in which values get smaller by factors of ten as you read from left to right. If we continue doing this, then the number to the right of a single unit represents tenths of that unit. A decimal point is then used to mark the boundary between the whole units and tenths of that unit.

For instanc
Author(s): The Open University

Many different systems for writing numbers have been developed over the history of humankind.

The easiest way of counting small numbers is to use your fingers, and for this reason many numerical systems, such as the decimal system, are based around the number ten. But what happens when you run out of fingers to count on?

Numbering systems get round this problem by using a system of scale in which many small units are represented by a single larger unit, and many of these la
Author(s): The Open University

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

• understand the decimal system of numbering (hundreds, tens, units);

• explain the best way to write down decimal numbers and associated units of measurement in the healthcare workplace, in a manner that avoids confusion;

• understand the concepts of discrete and continuous variables and the best types of graphs used to represent these data;

• analyse, construct and extract information from grap
Author(s): The Open University

This sample of S110 material is taken from Module 2, entitled Using numbers and handling data. As you read the material, bear in mind that it is taken from a work-based course, designed for those who are employed in the health services, perhaps as a paramedic or as operating theatre staff. If you were a student on the course, you would have an OU tutor to help you, plus a work-based mentor supplied by the employer â€“ normally the NHS. The aim is to use the workplace as a teaching aren
Author(s): The Open University

The content acknowledged below is Proprietary (see terms and conditions). This content is made available under a Creative Commons Attribution-NonCommercial-ShareAlike 2.0 Licence

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

## Author(s): The Open UniversityLicense informationRelated contentExcept for third party materials and/or otherwise stated (see terms and conditions) the content in OpenLearn is released for use under the terms of the Creative Commons Attribution-NonCommercial-Share

Now you have completed this unit, try the following questions to test your understanding of this material.

## Question 19

• A discrete exotic terrane refers to a large crustal fragment that can be recognised by its distinct sedimentary, igneous, metamorphic and structural history compared with that of its eventual neighbours, and has been juxtaposed into position by major strikeâ€“slip faults.

• Nine discrete exotic terranes make up the Basement in the British Isles. These consist primarily of Precambrian metamorphosed rocks but also contain some unmetamorphosed sedi
Author(s): The Open University

This unit is an adapted extract from the course Biological psychology: exploring the brain (SD226)

This unit looks at how language is understood, which includes hearing and how sounds and words are interpreted by the brain. It takes an interdisciplinary approach and should be of wide general interest.

Author(s): The Open University

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

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

## Author(s): The Open UniversityLicense informationRelated contentExcept for third party materials and/or otherwise stated (see terms and conditions) the content in OpenLearn is released for use under the terms of the Creative Commons Attribution-NonCommercial-Share

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
Author(s): The Open University

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

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
Author(s): The Open University

Blakemore, C. and Cooper, A. (1970) Development of the brain depends on visual environment, Nature, 228, pp. 477â€“8.
Caspi, A., McClay, J., Moffitt, T. E., Mill, J., Martin, J., Craig, I. W., Taylor, A. and Poulton, R. (2002) Role of genotype in the cycle of violence in maltreated children, Science, 297, pp. 851â€“4.
Caspi, A., Sugden, K., Moffitt, T. E., Taylor
Author(s): The Open University

The effects of a protein that is absent, or present but not doing its job, may not be evident for many years. This is called late onset, and is exemplified by Wilson's disease. Many molecules within the body require small amounts of minerals such as iron, magnesium or copper to function properly. There are mechanisms for absorbing these minerals from the diet. However, in excess, these same minerals can be toxic, as is the case with copper. So there are also mechanisms for getting rid
Author(s): The Open University

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.

Author(s): The Open University

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 â€˜cobalaminâ€™. 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
Author(s): The Open University

Folate is a generic name for a group of related compounds. The name â€˜folateâ€™ was based on the word â€˜foliageâ€™, 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
Author(s): The Open University

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
Author(s): The Open University

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
Author(s): The Open University