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Paragraphs and Topic Sentences 

A paragraph is a series of sentences about a single topic. The paragraph is one of the basic organizational features of an essay—it provides a clear division between the arguments, facts, or other information you present and allows a specific space for you to develop and put forward your ideas on each topic or narrate separate events. We can break the paragraphinto three major elements, the introduction, body and conclusion.

Introduction

·      A paragraph can have an introductory sentence that provides necessary background information about the topic of the paragraph. If no background information is necessary, or if it is already provided earlier in the essay, then you do not need to include this sentence.

§ Limb regeneration has been an intriguing field of study in the past decade, but little progress has been made to actually regenerate a human limb.

·      A paragraph can have a sentence that connects the topic of the paragraph to the ideas of the previous paragraph, if the connection is not already clear. This sentence is called a transition.

§ Just like the spotted tree toad, the spine-tailed lizard has the ability to regenerate.

·      Every paragraph should have a topic sentence. The topic sentence puts forward the topic of the paragraph.

§ The spine-tailed lizard’s ability to regenerate is particularly interesting for scientists studying the possibility of human regeneration.

o  The topic sentence frequently provides a transition by connecting to the previous paragraph’s topic sentence.

·      You can also combine the functions of all three of these sentences into one or two sentences in some cases.

§ Just like the spotted tree toad, the spine-tailed lizard can also regenerate its limbs—a function that has been heavily studied in the past decade, but little progress has been made to actually regenerating human limbs. Many scientists think the spine-tailed lizard is particularly interesting for furthering their research on regenerating human limbs.

Note: Sometimes the introductory sentence and transition are not necessary because the topics of the previous and current paragraphs flow logically into one another. In this case, just start with the topic sentence. When you are having difficultly deciding which strategy to use, consult your instructor or other readers to see how they react.

Body

·      The body of the paragraph analyzes the evidence, facts, opinions, narratives, descriptions, quotes, or examples related to the topic of the paragraph.

·      The body of the paragraph should clearly relate, either implicitly or explicitly, to the larger argument or subject of the essay.

§ Scientists have determined that the spine-tailed lizard’s subgenerative cuticle glands contribute to the regeneration of the spines on the lizard’s tail, but they have not discovered the catalyst that causes the glands to begin working. Scientists have, however, found a similar-functioning gland in humans. Scientist Stephen Mayer (2006) claims that “We are very close to discovering how this lizard regenerates its limbs, but the bigger challenge will be transferring the results to the human body” (45).  

Conclusion

·      The conclusion emphasizes and extends the main point of the paragraph.

§ Although the spine-tailed lizard research group hopes to discover the connection between the lizard’s regeneration and the possibility of human regeneration soon, it seems that getting closer to understanding the lizard only brings more questions about how to apply that data to human regeneration.

Paragraph Unity

·      Each sentence in your paragraph should be clearly related to the topic sentence so that the reader is not surprised or confused by how your argument flows.

o  Remember that these guidelines are generally appropriate for academic writing. For creative writing or writing in other cultures, the expectations may be different. If you have questions about how to approach your writing you should ask your professor.

Example Paragraph

The topic sentence of this paragraph is in bold. The thesis of this essay is “Limb regeneration has been an intriguing field of study in the past decade, but little progress has been made to regenerate a human limb.”

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