Download Life Science: Cells

Life Science: Cells
Teacher’s Guide
Grade Level: 6–8
Curriculum Focus: Life Science
Lesson Duration: 2 class periods
Program Description
Everybody is made up of trillions of cells, each working like a tiny factory that does its part to
“manufacture” what’s needed to keep the body going. Inside the cell membrane is a nucleus, which
holds the cell’s DNA, and organelles that carry out the cell’s specific task. Red blood cells are expert
transporters of oxygen and carbon dioxide. White blood cells attack invading germs. All reproduce by
mitosis, or cell division. A glitch in this process can lead to the growth of cancerous cells that crowd out
healthy ones. Cells’ ability to replicate is what keeps every living thing alive. But when the process goes
awry, that ability threatens health and can be deadly.
Discussion Questions
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What are the cell membrane, nucleus, and organelles and what do they do for the cell?
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How do cells reproduce?
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Describe the unique properties of red and white blood cells and their functions.
• How do skin cells help protect the body, and what effect does ultraviolet radiation have
on skin cells?
• What is the process by which a regular cell begins to replicate indefinitely and becomes
cancerous?
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Why are cancer cells damaging to the body?
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What is the single-celled organism that produces sores on fish and ultimately kills them?
Lesson Plan
Student Objectives
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Discover and understand the parts and functions of cells.
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Create and draw cartoon characters with the features of different cells.
Life Science: Cells
Teacher’s Guide
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Materials
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Computer with Internet access
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Print resources about cells
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Paper and markers or other art supplies
Procedures
1. Review with the class the parts of a cell and the jobs carried out by each part. The Cells
Alive! Web site (www.cellsalive.com) can be very helpful for the review. There you can see
interactive diagrams featuring the parts of both plant and animal cells and watch animations
of cell division.
2. Because cells are such mighty little things, it’s not much of a leap to think of them as tiny
superheroes. For example, the Dynamic Dermo (skin cell) may only live three weeks, but it has
the power to fend off bacteria, shield sunrays, and keep the body temperature steady. Students
will appreciate cells’ superpowers better when they each choose a type of cell and create a
superhero that represents the cell’s abilities and special features.
Encourage students to be creative, but, at a minimum, each report should include a drawing of
the superhero cell, a fitting name, costume, and a character sketch or bio that includes details
about the cell’s abilities. Remind them that not all cells are good guys. Some students may
choose to create villains that hail from the constellation Cancer, for example. After everyone has
compiled their characters, have students work in small groups to write and illustrate a comic
strip featuring their heroes and villains. For example, what happens when Lucky Leukocyte
meets the evil Bacteria Boy?
3. The following Web sites will provide students with inspiration to create their characters:
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BBC’s Cell Biology
http://www.bbc.co.uk/education/asguru/biology/01cellbiology/index.shtml
and Bitesize Revision: Life Processes and Cells
http://www.bbc.co.uk/schools/ks3bitesize/science/biology/lifecells1_2.shtml
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Cells Alive!
http://www.cellsalive.com/
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How Cells Work
http://science.howstuffworks.com/cell.htm
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Neuroscience for Kids: Neurons
http://faculty.washington.edu/chudler/cells.html
Published by Discovery Education. © 2005. All rights reserved.
Life Science: Cells
Teacher’s Guide
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Assessment
Use the following three-point rubric to evaluate students’ work during this lesson.
3 points: Students were highly engaged in class discussions; produced a complete cell
superhero, including all of the requested information; and collaborated on an informative,
creative comic strip.
2 points: Students participated in class discussions; produced an adequate cell superhero,
including most of the requested information; and collaborated on an average comic strip.
1 point: Students participated minimally in class discussions; created an incomplete cell
superhero with little or none of the requested information; and did not collaborate well in
producing the comic strip.
Vocabulary
cell
Definition: The smallest independently functioning unit in an organism; cells contain nuclei and
organelles inside a membrane.
Context: The human body is made up of trillions of cells.
cell membrane
Definition: The structure that surrounds a cell
Context: The cell membrane is semipermeable, which means it allows things such as food and
waste to pass in and out of the cell.
DNA
Definition: An acid found in a cell nucleus that carries the genetic information a cell needs
to replicate
Context: DNA is short for deoxyribonucleic acid.
hemoglobin
Definition: The compound found in red blood cells that carries oxygen
Context: Hemoglobin is what gives red blood cells their color.
mitosis
Definition: Cell division
Context: Cells reproduce by mitosis, a process in which a cell’s nucleus and other parts split into
two new cells.
nucleus
Definition: The control center of a cell, which contains DNA and regulates the cell’s functions
Context: You can think of the nucleus as the cell’s “brain.”
Published by Discovery Education. © 2005. All rights reserved.
Life Science: Cells
Teacher’s Guide
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organelle
Definition: A structure within a cell that has a specific function
Context: Examples of organelles are mitochondria, which provide the cell with energy, and
vacuoles, which get rid of cellular waste.
transformation
Definition: The process by which a normal cell begins to replicate indefinitely, becoming a
cancerous cell
Context: After transformation, a cell multiplies out of control and can crowd out normal cells.
Academic Standards
National Academy of Sciences
The National Science Education Standards provide guidelines for teaching science as well as a
coherent vision of what it means to be scientifically literate for students in grades K–12. To view the
standards, visit this Web site:
http://books.nap.edu/html/nses/html/overview.html#content
This lesson plan addresses the following national standards:
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Life Science: Structure and function in living systems; Reproduction and heredity;
Regulation and behavior
Mid-continent Research for Education and Learning (McREL)
McREL's Content Knowledge: A Compendium of Standards and Benchmarks for K–12 Education
addresses 14 content areas. To view the standards and benchmarks, visit
http://www.mcrel.org/compendium/browse.asp
This lesson plan addresses the following national standards:
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Science: Life Sciences—Understands the principles of heredity and related concepts;
Understands the structure and function of cells and organisms
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Language Arts: Viewing—Uses viewing skills and strategies to understand and interpret
visual media; Writing—Uses the general skills and strategies of the writing process, Gathers
and uses information for research purposes; Reading—Uses reading skills and strategies to
understand and interpret a variety of informational texts
Support Materials
Develop custom worksheets, educational puzzles, online quizzes, and more with the free teaching tools
offered on the Discoveryschool.com Web site. Create and print support materials, or save them to a
Custom Classroom account for future use. To learn more, visit
Published by Discovery Education. © 2005. All rights reserved.
Life Science: Cells
Teacher’s Guide
•
http://school.discovery.com/teachingtools/teachingtools.html
Published by Discovery Education. © 2005. All rights reserved.
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