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UNIT 1 - Ch5-CELL
STRUCTURE & FUNCTION
P. 87-102
TYPES OF CELLS

Cells come in a variety of shapes and sizes
that suit their diverse functions.
OBJECTIVES
1. Explain the relationship between cell shape
and function.
2. Identify the factor that limits cell size.
3. Describe the three basic parts of a cell.
4. Compare prokaryotic cells and eukaryotic
cells.
5. Compare plant and animal cells
6. Know the organelles and their functions
CELL DIVERSITY

Not all cells are alike.
Even cells within the
same organism show
Enormous Diversity
in Size, Shape, and
Internal Organization.
Your Body contains
at least 200 Different
Cell Types.
CELL SHAPE

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Most Cells have a Specific Shape.
THE SHAPE OF A CELL DEPENDS
ON IT'S FUNCTION.
Cells of the Nervous System that carry
information from your toes to your brain
are long and threadlike.
Blood Cells are shaped like round disk
that can squeeze through tiny blood
vessels.
CELL SIZE

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A few types of cells are large enough to be
seen by the unaided eye. Eg. The Female
Egg
Most cells are visible only with a
microscope.
MOST CELLS ARE SMALL FOR
TWO REASONS:
#1-Cells are limited in size by the RATIO of their
Surface Area to Volume.
The ration of Surface Area / Volume decreases as the cell size
increases. (less SA compared to the Vol)
This is important because the nutrients, oxygen, and other
materials a cell requires must enter through it surface &
waste must exit
#2 – Processes such as Diffusion are slow and
inefficient over large distances which limits
nulceus ability to controle lg cells and effeciency
of nutrient exchange within the cell
COMPARING CELLS
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All cells share common features, such as a
plasma membrane, cytoplasm, ribosomes,
and genetic material (DNA).
But there is a high level of diversity among
cells, there are significant differences
between prokaryotes and eukaryotes. In
addition plant cells have features that are
not found in animal cells, although fungi ,
plant and animal cells are eukaryotic cells.
EUKARYOTIC vs
PROKARYOTIC CELLS
1. Prokaryotes differ from eukaryotes in that
prokaryotes Lack a Nucleus and Lack
Membrane-Bound Organelles.
2. In place of a nucleus, prokaryotes have a
region called a Nucleoid in which their
genetic material is concentrated.
3. Prokaryotes lack an internal membrane
system.
CELLS ORGANELLES
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You are responsible to know all of the cells
organelles.
You must be able to name, identify, and
know the functions of them all
Read p. 89-98 and complete the structure
function graph provided
THIS IS REVIEW FROM LAST YEAR
You will have a quiz on these next class!