Academic Writing for International Students of Science - Jane Bottomley 2015
6.1 Information structure
6 Paragraph development: achieving flow
In this chapter, you will examine some of the characteristics of typical English paragraph structure, and learn how to develop your own paragraphs in a clear way.
A paragraph is well developed if there is a logical connection between ideas, and the words, sentences and ideas flow in such a way that the reader is able to follow easily.
Which of the student’s two drafts below is easier to read? Why?
The dithiocarbamate drug disulfiram is used in the treatment of alcohol abuse. The drug induces apoptosis* in cancer tumours. It has recently been discovered that disulfiram has potential therapeutic capabilities.1 It has been reported that disulfiram in combination with copper (II) salts causes apoptosis in a chemotherapy-resistant cancer cell line.2 The copper complex of the drug enhances the result against the tumour cells.
The dithiocarbamate drug disulfiram is primarily used in the treatment of alcohol abuse. Recently, however, other potential therapeutic capabilities have been discovered.1 It has been reported that disulfiram causes apoptosis in a chemotherapy-resistant cancer cell line. This effect is enhanced if the drug is used in combination with copper (II) salts.2
Text A is the student’s first draft. Although accurate and well-expressed on the whole, it is a little hard to follow because some information is repeated at different points and it is not as concise as it could be. Text B is the student’s second draft. It flows clearly and concisely from point to point, and uses certain expressions (primarily/other; however; this effect) to make logical connections.
Things which contribute to flow are:
✵ information structure
✵ cohesive devices
These will be discussed in the following sections.
6.1 Information structure
One thing which can aid flow is the structuring of information in a clear, logical way. Information structure can differ across languages, so there are some specific things about English information structure which you need to be aware of.
6.1.1 Given versus new information
The order of information can contribute significantly to how a text flows.
1) Look at the paragraphs below and decide which one is easiest to read.
Food additives are substances that are added to food to improve shelf-life, appearance and flavour. Vinegar and salt are two substances which have been added to food for centuries. Modern food processing has led to the use of many more additives, both natural and artificial.
Food additives are substances that are added to food to improve shelf-life, appearance and flavour. Two substances which have been added to food for centuries are vinegar and salt. Many more additives, both natural and artificial, are now used in modern food processing.
Geckos, harmless tropical lizards, are extremely fascinating and extraordinary animals. They have very sticky feet that cling to virtually any surface. This characteristic makes it possible for them to rapidly run up vertical walls and along the undersides of horizontal surfaces. In fact, a gecko can support its body mass with a single toe! The secret to this remarkable ability is the presence of an extremely large number of microscopically small hairs on each of their toe pads. When these hairs come into contact with a surface, weak forces of attraction (i.e. van der Waals forces) are established between hair molecules and molecules on the surface. The fact that these hairs are so small and so numerous explains why the gecko grips surfaces so tightly. To release its grip, the gecko simply curls up its toes, and peels the hairs away from the surface.
Geckos, harmless tropical lizards, are extremely fascinating and extraordinary animals. They have very sticky feet that cling to virtually any surface. They are able to rapidly run up vertical walls and along the undersides of horizontal surfaces, thanks to this characteristic. In fact, a gecko can support its body mass with a single toe! The presence of an extremely large number of microscopically small hairs on each of their toe pads is the secret to this remarkable ability. Weak forces of attraction (i.e. van der Waals forces) are established between hair molecules and molecules on the surface when these hairs come into contact with a surface. The fact that these hairs are so small and so numerous explains why the gecko grips surfaces so tightly. The gecko simply curls up its toes, and peels the hairs away from the surface to release its grip.
Texts 1 B (adapted from The Royal Society) and 2 A (Callister, 2007: 15) are the original texts. Both have a typical English information structure in that each sentence first refers back to the main theme of the previous sentence and then adds new information. This maintains the flow of information. (In contrast, in 1 A and 2 B, the link to what has gone before is delayed, making it difficult to follow.)
This given → new structure also allows for another common feature of English, end focus, whereby new information comes at the end of the sentence, where it has more prominence.
2) Look back at the texts 1 B and 2 A and underline the words/phrases which link back to information already given. (The use of such links is examined further in 6.2.)
Rewrite these short texts to reflect the given → new structure exemplified above.
1) Cereals are one of the most important staple foods. Wheat, rye, barley, oats, maize, rice, millet and sorghum are the major cereals of the world.
2) Beer is a fermented alcoholic beverage. Malt and hops are the main ingredients of beer.
3) A ligament is a resilient but flexible band of tissue that holds two or more bones together at a moveable joint. Movement of bones at a joint is restrained by ligaments and therefore they are important in preventing dislocation.
4) Chalk is a very fine-grained white rock composed of the fossilised skeletal remains of marine plankton and consisting largely of calcium carbonate. Toothpaste and cosmetics use chalk. However, blackboard ’chalk’ is not the same thing. It is made from calcium sulphate.
6.1.2 General and specific
Sentences in a paragraph must be logically ordered, and often follow a linear general → specific pattern. It is also common to make the first sentence a sort of general ’umbrella’ (i.e. covering the rest of the paragraph) statement, which introduces the main theme of the paragraph: this is often referred to as the topic sentence. Subsequent sentences will expand in some way on this, by providing support such as explanation or exemplification.
Look at how the paragraphs below are introduced and developed, and match each sentence with a description of its function in the paragraph, making particular note of the topic sentence in each.
Infectious diseases remain a major threat to global animal and human health. Recent examples include the 2002 Foot and Mouth Disease outbreak in the UK, the 2003 global epidemic of SARS and the threat of an influenza pandemic. The control of infectious diseases in animals and humans is a problem that needs to be addressed by scientists, veterinarians, healthcare workers, economists, social scientists and policy makers.
(Adapted from The Royal society)
a) gives examples
b) introduces the threat of infectious diseases
c) states the need for problem to be addressed
Unless a patient needing an organ has an identical twin, there will always be immunological differences between the patient and the transplanted organ. These differences are immediately recognised by the recipient’s immune system, and, depending on how closely the donor and recipient were matched, cause a reaction intended to destroy the transplanted organ. Consequently, transplant patients are placed on drug regimens designed to lessen the immune response against the organ to prevent rejection. These drugs reduce the chances of rejection by diminishing the patients’ overall immune capability. However, this causes the patient to be more susceptible to infection.
(Strelkauskas et al., 2010: 106)
a) states the problem
b) explains the negative side effects of the drugs
c) introduces the current solution to the problem (drugs)
d) explains how the drugs work
e) introduces the issue of immunological differences in organ transplant patients
The Capsicum family includes a wide variety of peppers ranging from the large sweet peppers to the fiery chilli peppers. Chilli peppers derive their hotness from capsaicin and dihydrocapsaicin (members of the capsaicinoid family), and restaurants specializing in ’hot’ foods owe much to these molecules of nature. They work by interacting with the same receptors in your mouth that sense heat. Excessive amounts of capsaicin are toxic because capsaicin prevents the production of certain neurotransmitters and affects the function of neuroproteins in the brain. At high enough concentrations, capsaicin destroys ’substance P’ in the nervous system. This effect has now been harnessed for medical use: ’substance P’ is associated with the pain suffered by people with, for example, arthritis and inflammatory bowel disease, and application of a cream containing capsaicin results in pain relief.
(Housecroft and Constable, 2010: 1215)
a) explains the source of chilli heat
b) introduces the capsicum family
c) explains the toxic nature of one ’heat’ molecule — capsaicin
d) gives examples of medical uses of capsaicin
e) explains the effects of capsaicin
f) explains how the ’heat’ molecules produce heat
Note the verbs in bold (introduce; state; give; explain), which show that each sentence has a clear role, or function in the paragraph. For example, it can be clearly seen from the above texts that the role of the topic sentence is usually to introduce the main theme of the text. Think about what you want each sentence to do in your text.
Put the sentences below in order to form well-developed paragraphs. Take care to identify the topic sentence.
1)____ 2) _____ 3)_____ 4)_____5)____
a) More efficient fluorescent lighting has since been developed, but suffers from flicker and colour purity issues.
b) They are already used in traffic lights and even in museums to illuminate paintings.
c) Lighting has not changed much since the light bulb was invented by Edison and others close to a hundred years ago.
d) LEDs exhibit tremendous brightness, consume little power, come in different colors, and emit little or no heat.
e) Recently, solid state light-emitting diodes (LEDs) have come on the market and are poised to revolutionise the lighting industry.
(Kuno, 2012: 419—420)
1)____ 2) _____ 3)_____ 4)_____5)_____ 6)_____ 7) _____ 8)____
a) ’Triggers’ external to the climate system, such as changes in the Earth’s orbit or a brightening or dimming of the sun, could bring this about; so could internal triggers such as emissions of climate-altering gases into the atmosphere.
b) However, palaeoclimatic records show that large, abrupt changes to the global climate have occurred frequently.
c) Temperature changes of up to 16 degrees Celsius and precipitation doublings, for example, have occurred in periods as short as decades or less (Committee on Abrupt Climate Change, National Research Council, 2002) and might therefore presumably happen again.
d) The majority of climate scientists believe the world is in a period of climate warning and associated environmental change and that this is likely to continue for a long time, with significant impacts on human health around the globe.
e) Projected changes this century, while alarming, are envisaged as relatively gradual, making adaptation to the changes easier than would be the case with larger and more abrupt change.
f) Such changes occur when a threshold in the climate system is crossed.
g) This would clearly have enormous impacts on global health futures.
h) This raises the question of whether human-induced greenhouse gas emissions might ultimately trigger abrupt, larger climate change than is currently predicted.
(McCracken and Phillips, 2012: 287—288)