14 ­ Regeneration and Stem Cells.notebook
March 28, 2017
March 28, 2014
Warm­up: How long does it take for a lobster claw to grow back?
30 days
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14 ­ Regeneration and Stem Cells.notebook
March 28, 2017
Answers Pg 181 #1­3
1. Cancer is a group of diseases caused by uncontrolled, unregulated cell division.
2. Mutations are changes in the genetic code. 3. Cancer cells differ from other cells because they divide in isolation, they are not specialized to a certain function, and they take resources and energy from surrounding cells in order to reproduce. 2
14 ­ Regeneration and Stem Cells.notebook
March 28, 2017
Regeneration p. 186
• Regeneration is the ability to regrow a
part of the body.
• Animals with little specialization can
regenerate limbs or body parts
• e.g. sponges, planaria (worms), sea stars,
newts, etc.
• Specialization refers how cells develop
different structures and functions,
depending on their role in multicellular
organisms.
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14 ­ Regeneration and Stem Cells.notebook
March 28, 2017
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14 ­ Regeneration and Stem Cells.notebook
March 28, 2017
Human Regeneration
What parts are humans able to re­generate? In humans, blood, bone and skin can regrow or regenerate. Bones that break can be repaired; broken skin (a cut) can heal; fingertips can regenerate. A human liver or kidney has some ability to regenerate.
What are humans not able to re­generate? We can not regrow entire fingers, toes, arms etc.....
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14 ­ Regeneration and Stem Cells.notebook
March 28, 2017
Why can humans/other animals regenerate
certain parts and not others?
• Humans and some other animals, like
earthworms, have many kinds of
specialized cells like liver, brain, skin,
blood.
• Because of this specialization, we do not
regenerate these cells. 6
14 ­ Regeneration and Stem Cells.notebook
March 28, 2017
Stem Cells
• Stem cells are cells with little
specialization. They are able to divide
many times and they specialize into
something like a muscle or nerve cell.
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14 ­ Regeneration and Stem Cells.notebook
March 28, 2017
• Human skin, bone marrow, contains stem
cells. This is why we can grow new skin
cells, but not new nerve cells.
• Research is being done now on stem cells.
They are looking for ways to repair cells
that can not be replaced.
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14 ­ Regeneration and Stem Cells.notebook
March 28, 2017
pg 187 # 1­4
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14 ­ Regeneration and Stem Cells.notebook
March 28, 2017
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