Download Ch 7 Cell Structure and Function

Ch 7 Cell Structure and
Function
7-1 Life Is cellular
7-2 Eukaryotic Cell Structure
7-3 Cell Boundaries
7-4 The diversity of Cellular Life
7-1 Introduction to Cells
• A Cell is the smallest unit of matter that can
•
carry on all of the processes of life
The Cell Theory
• All living things are composed of one or more
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•
cells
Cells are the basic units of structure and
function in an organism
Cells come only from the reproduction of
existing cells
7-1 Introduction to Cells
• Cell Diversity
• Size is limited by the volume to surface
area
• Nutrients, Oxygen and other materials must enter
the cell through the surface
• If the volume becomes to high then the cell cannot
get proper nutrients and will die
• Adaptations might be to flatten or to create folds
Surface Area to Volume Ratios
6 to 1
3 to 1
1 to 6
7-1 Introduction to Cells
• Shape- Cells come in a variety of shapes
including
• Nerves-long appendages for sending impulses
• Skin- Flat dead cells to insulate and cover surface
• Blood- Round, but change shape to move through
narrow opening in your body
Which one is Blood, Nerve or Skin?
7-1 Introduction to Cells
• Internal Organization
• Each cell contains different components that
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•
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perform specific tasks called Organelles
(example- Nucleus)
The entire cell is surrounded by a thin
membrane called the Cell Membrane
If the nucleus is surrounded by a membrane
then the cell is from a Eukaryote
If the nucleus is not membrane bound then it is
from a prokaryote
Notice the DNA in the Eukaryote is
membrane bound while the
Prokaryote is not.
Questions from the Book
• Do in your Notebook
• Pg 173 #1-5
7-2 Parts of the Eukaryote Cell
• Organelles “little Organs”
• All of the space between the cell membrane and
•
the nucleus where the organelles rest is called
the cytoplasm
Mitochondria- Organelle in the cell that turns
organic compounds (sugars) into ATP.
– Mitochondria are numerous in cells that have high
energy requirements such as muscles
7-2 Parts of a Eukaryote Cell
• Ribosome- Free floating or attached organelles
within the cytosol that synthesizes proteins
– Not membrane bound, most numerous organelle in
cell
• Endoplasmic Reticulum (ER)- Considered
intracellular highways for Ribosome's to moveThere are Two Varieties
7-2 Parts of a Eukaryote Cell
• Golgi Apparatus- Working in close
association with the ER, it modifies
proteins for export by the Cell
• Lysosomes- Small, spherical organelles
that enclose enzymes within its membrane
7-2 Parts of a Eukaryote cell
• Cytoskeleton- Series of proteins that give your
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•
cells their shape
Microfilaments- composed of actin, they are
small threads that assist in cell movement
Microtubules- hollow tubes that extend outward
from the center of the cell
– Centrioles are in the center of the cell and help in cell
division
• Cilia and Flagella are hair like organelles that
extend from the surface of the cell to assist in
movement
Cytoskeleton giving the Cell its Shape
7-2 Parts of a Eukaryote Cell
• Nucleus
– Often the most prominent structure within a
eukaryotic cell
• The nucleus is surrounded by a double
membrane called the Nuclear Envelope
– Inside the nuclear envelope is a combination of DNA
and proteins called Chromatin
– When the cell is about to divide the chromatic coils up
and becomes Chromosomes
• Area where ribosome's are made in the nucleus
is called the Nucleolus, then they pass through
nuclear pores into the cytosol
The Nucleus of a Eukaryotic Cell
7-2 Parts of a Eukaryotic Cell
• Plants have all Organelles in Eukaryotic cells
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•
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with 3 additional ones vital to survival
Cell Wall- Very Rigid cell membrane composed
of cellulose for support and protection
Vacuoles- Fluid Filled organelles that store
enzymes and metabolic waste
Plastids- Accessory organelles for storing fats
or starches. The more familiar type of plastid is
Chloroplast, which is used to turn light energy
into chemical energy
Everything described plus 3 more structures
In Notebooks
• Pg 181 1-5
7.3 notes on separate slideshow
7.4 The diversity of Cellular Life
• Unicellular organisms do everything
described in the characteristics of life
(grow, use energy, multiply…)
7.4 The diversity of Cellular Life
• Cells throughout an organism can develop
in different ways to perform different
tasks This process is called Cell
Specialization
7.4 The diversity of Cellular Life
• The levels of organization in a multicellular
organism are
– Individual cells
• Tissue-group of similar cells that perform
a particular function
7.4 The diversity of Cellular Life
• Multiple tissues
working together to
complete a task is
called an Organ
– Connective tissue and
nerves in a muscle
• Groups of Organs
make up an Organ
system that carry out
a series of tasks
7.4 The diversity of Cellular Life
• Pg 193 (1-4)