Download How can one cell become a multicellular organism?

3/29/2012
How can one cell
become a multicellular
organism?
Levels of Organization
• How do unicellular and multi-cellular
organisms differ?
• How does cell differentiation lead to the
organization within a multi-cellular
organism?
Levels of Organization
• cell differentiation
• stem cell
• tissue
• organ
• organ system
Unicellular Organisms
Unicellular Organisms (cont.)
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Multi-cellular Organisms
Multi-cellular Organisms (cont.)
cell
differentiation
How do unicellular and
multicellular organisms differ?
Multi-cellular Organisms (cont.)
Stem cells
Tissues are groups of similar types of cells
in multi-cellular organisms that work
together to carry out specific tasks.
tissue
from Latin texere, means “weave”
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• Humans, like most other animals, have
four main types of tissue: muscle,
connective, nervous, and epithelial.
• Organs are groups of different
tissues working together to perform
a particular job.
• The three main types of plant tissue are
dermal, vascular, and ground tissue.
Organ systems are groups of different
organs that work together to complete a
series of tasks.
Multi-cellular Organisms (cont.)
How does cell differentiation lead to the
organization within a multi-cellular
organism?
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• A unicellular organism carries out all
the activities necessary for survival
within one cell.
• Cells become specialized in structure
and function
during cell
differentiation.
• Organs are groups of different tissues
that work together to perform a job.
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