Download THE CELL

THE CELL
• Cells are mainly formed of water, but present in
their structure are proteins, carbohydrates, and
nucleic acids (DNA).
Structure
• Cell membrane
• Cell wall
• Nucleus
THE CELL
Cell Membrane
• Separates the parts inside the cell from the
outside
• Support for the cytoskeleton, shape for the cell
• Substances pass through it
• Cell communication
THE CELL
Cell Wall
• Strength and rigidity
• Protection
• Retains water
• It is different between eukaryotes and
prokaryotes and plants and fungi
THE CELL
Workshop
• Make a scheme where you compare all the
different types of cells there are.
• List the differences between the cell wall and
the cell membrane
HOMEWORK:
Bring information about the cell organelles and its functions.
In groups: classify the organelles of the cell according to the processes
related to their functions.
THE CELL
ANIMAL
CELL
http://www.enchantedlearning.com/subjects/animals/cell/
THE CELL
PLANT
CELL
http://www.enchantedlearning.com/subjects/plants/cell/
THE CELL
Organelles
• In groups:
– Each member of the group brings information of the
cell’s organelles and their function.
– Discuss about how those organelles and structures
influence the function of the cells. Write your
conclusions.
– Make a scheme or model of a plant and animal cell
indicating all its organelles and functions.
THE CELL - Transport
Cell Membrane  Phospholipids have both hydrophilic
and hydrophobic regions: nonpolar tails (hydrophobic),
polar heads (hydrophilic)
THE CELL - Transport
Cell Membrane  It also has proteins in the
membrane, which function is regulate the movement
of some substances
THE CELL - Transport
Release wastes and take
in some substances
PASSIVE
TRANSPORT
Cell membrane: acts as
selectively permeable
screen.
Movement of molecules
between areas of different
concentrations
THE CELL - Transport
PASSIVE TRANSPORT: no energy is needed
• Diffusion: movement of molecules -like oxygen- from
areas of high concentration to areas of low
concentration.
• Osmosis: movement of WATER through a
semipermeabe membrane from areas of lower
concentrations to areas of higher concentrations.
THE CELL - Transport
Solutions can be:
Isotonic: same concentrations, there is an equilibrium
Hypotonic: lower concentrations of dissolved solutes on the
outside, therefore water moves into the cell
Hypertonic: higher concentrations of dissolved solutes on the
outside, therefore water moves out of the cell
THE CELL - Transport
THE CELL - Transport
Active Transport: energy is needed
Allows the movement of molecules from an area of low
concentration to an area of high concentration. THIS
REQUIRES ENERGY!!  sodium - potassium pump
Endocytosis: membrane surrounds the molecule that is
going to be taken inside…
Exocytosis: membrane surrounds the molecule that is
going to be pushed outside…
THE CELL
Presentations:
PHOTOSYNTHESIS, RESPIRATION, FERMENTATION
Instructions:
1.Explain the process
2.Prepare an activity related to the topic
References
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•
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http://library.thinkquest.org/3564/
http://www.cellsalive.com/cells/cell_model.htm
http://www.biologycorner.com/bio1/diffusion.html#
https://docs.google.com/a/clermont.edu.co/present/vi
ew?id=dfh23k67_3097ckdwv8d5