Finding main idea, supporting details, marking a
textbook, and charts to organize information
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A reading, like an essay, has an introduction
(usually the first paragraph), and a conclusion
(the last paragraph).
Often, one sentence in the introduction gives
the main idea of the reading.
The main idea is the most important idea.
It includes all of the smaller, more specific
ideas of the reading.
Frequently, the main idea appears again in
the conclusion.
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Sometimes you can find important details
(specific points) quickly if you look for
numbers or words such as first, second, next,
finally (transition words).
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Sometimes you have a lot of reading to do,
and there usually is not enough time to read
a chapter several times.
You need to highlight the important
information in a reading so that you can find
it quickly later.
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Use one color for main ideas.
Use a different color for important details.
Be sure not to highlight too much
information.
Sometimes you can highlight key words
instead of highlighting an entire sentence.
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When you read a section of a textbook, you
can often find the main idea for the reading
in the introductory paragraph and in the
concluding paragraph.
In the other paragraphs of a reading, the
main idea of each paragraph is usually found
in the first sentence. This is the topic
sentence It’s a good idea to highlight the
topic sentences as you read.
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Graphic organizers are useful study tools that
can allow you to record information such as
main ideas, important details, and examples
from a reading.
They can allow you to see relationships
among ideas.
One type that is good for note-taking is a
chart.
Question
What is biotechnology?
What is genetic
engineering?
What can genetic
engineering do?
What is a gene?
What is a protein?
What are some
examples of
genetically modified
products?
Definition or
characteristics
Examples
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Read Background Information on Biotechnology.
(pages 57-59 only)
As you read, highlight the following:
◦ The topic sentence of each paragraph
◦ Definitions or characteristics of important terms
◦ Examples
Fill out the graphic organizer with the answers
to the questions and examples from the
reading.
Some of the information you highlighted may
help you with the chart.
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Share your findings with the rest of the class.
Using word, prepare a different chart with the
remaining questions on the reading. (pages
59-62)
Save your document on your computer.