Transcript The Cell

The Cell
An internet laboratory on the cell,
created by Wendy M. Rounds 5/3/00
The Cell
 Cells are the basic unit of life.
 Cells carryout all the necessary functions
for life such as: reproduction, taking in
nutrients and excreting wastes.
 Cells are made up of chemicals and
molecules. Human cells contain mostly
water.
The Cell
 Cells are classified as prokaryotic and
eukaryotic.
 Prokaryotic cells lack a well-defined
nucleus and many organelles. Bacteria are
prokaryotic cells.
 Eukaryotic cells include the protists, fungi,
plant and animal cells. We will study these
cells during this lab.
The Cell
Animal Cells
 Have centrioles
 Store glucose as
glycogen
 Do not have a cell wall
 Contain mitochondria
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Plant Cells
 Lack centrioles
 Store glucose as
cellulose or starch
 Have a cell wall
 Have large vacuoles
 Contain chloroplasts
as well as
mitochondria
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The Cell
Animal Cell
 Click on the cell to
study it in more detail
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 Plant Cell
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Click on the cell to
study it in more detail
Animal Cell
Click on each organelle to learn its function. When you have finished click on the
arrow button to study the plant cell.
Plant Cell
Click on each organelle to study its function. When you have finished click here
to study the animal cell or here to continue this lab.
Cell Extensions
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Two types of cellular extensions are cilia and flagella.
Cilia are small hairlike projections which beat to move
substances. The respiratory tract is lined with cilia which
only beat in one direction to move substances up from the
lungs. (then we swallow them)
Flagella (flagellum is the singular) are cellular
projections which help the cell to move. A flagellum is
found on sperm cells and helps them to swim to fertilize
the egg.
Lab Report
 Once you have reviewed the organelles of
the animal and plant cells. Open the Lab
Report which you downloaded from WebCT
with this file.
Nucleus
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Back
The nucleus is the controller of
the cell.
It is surrounded by the nuclear
envelope which controls what
substances may exit/enter the
nucleus.
It contains DNA and the
nucleolus.
DNA is termed the “genetic
blueprint” and directs all
protein synthesis.
The nucleolus makes
ribosomes.
Nucleus-Plant
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Back
The nucleus is the controller of
the cell.
It is surrounded by the nuclear
envelope which controls what
substances may exit/enter the
nucleus.
It contains DNA and the
nucleolus.
DNA is termed the “genetic
blueprint” and directs all
protein synthesis.
The nucleolus makes
ribosomes.
Ribosomes
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Free floating and
fixed:
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Endoplasmic
Reticulum
Cell
Ribosomes are protein
factories. All protein synthesis
occurs within the ribosome.
They may be fixed (attached to
the endoplasmic reticulum) or
free floating in the cytoplasm
They are composed of rRNA and
proteins.
Back
Ribosomes-Plant
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Free floating and
fixed:
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Endoplasmic
Reticulum
Cell
Ribosomes are protein
factories. All protein synthesis
occurs within the ribosome.
They may be fixed (attached to
the endoplasmic reticulum) or
free floating in the cytoplasm
They are composed of rRNA and
proteins.
Back
Endoplasmic Reticulum
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Back
The endoplasmic reticulum or
ER is a network of channels
which assist in the synthesis
and transport of cellular
products.
There are two types:
smooth ER which is involved in
the synthesis of lipid products
such as steroid hormones.
Rough ER which has ribosomes
attached to it & is involved in
protein synthesis.
Endoplasmic Reticulum-Plant
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Back
The endoplasmic reticulum or
ER is a network of channels
which assist in the synthesis
and transport of cellular
products.
There are two types:
smooth ER which is involved in
the synthesis of lipid products
such as steroid hormones.
Rough ER which has ribosomes
attached to it & is involved in
protein synthesis.
Golgi Apparatus
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This organelle consists of
tubular channels which
function to assemble, and
check proteins coming from
the rough ER.
The golgi apparatus also
ensures that the completed
proteins go to the appropriate
area of the cell. (that proteins
for the cell membrane get to
the membrane, proteins
hormones exit the cell etc.)
Back
Golgi Apparatus-Plant
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This organelle consists of
tubular channels which
function to assemble, and
check proteins coming from
the rough ER.
The golgi apparatus also
ensures that the completed
proteins go to the appropriate
area of the cell. (that proteins
for the cell membrane get to
the membrane, proteins
hormones exit the cell etc.)
Back
Lysosomes
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Lysosomes contain powerful
digestive enzymes which break
apart anything that gets inside
it.
They are important in
protection (splitting bacteria)
as well as, old organelles.
Lysosomes are able to release
the end products for reuse in
the cell.
It is important that the
lysosome doesn’t rupture or
the enzymes would digest the
cell.
Mitochondria
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Mitochondria are the
“powerhouses” of the cell.
They are responsible for
carrying out aerobic
cellular respiration.
This process forms ATP
from the food we eat and
requires oxygen.
Mitochondria-Plant
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Back
Mitochondria are the
“powerhouses” of the cell.
They are responsible for
carrying out aerobic
cellular respiration.
This process forms ATP
from the food we eat and
requires oxygen.
Cytoskeleton
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The cytoskeleton functions as
the “muscles and bones “of the
cell.
It consists of:
Microfilaments: which help the
cell to move (muscle
contraction)
Intermediate Filaments: which
prevent the cell from being
pulled apart.
Microtubules: function in
maintaining the cell shape.
Cell Wall
 Only found in plant cells
 Surrounds cell membrane
 Composed of lignin and cellulose
 Function to strengthen and protect plant
cells.
Back
Central Vacuole
 Large organelle
 Comsists of mostly water, plant pigments,
and toxins.
 Functions for storage of nutrients and
pigments, and retains waste products.
 The pigments which give a flower its color
are stored in the vacuole.
Back
Chloroplasts
Contain green
pigment termed
chlorophyll.
 Function in
photosynthesis
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Back