Download Cell Parts and Functions

Cell Structure and Function
What makes up cells? What do cell do?
1. Organism
2. Organ
System
3. Organ
4. Tissue
5. Cell
Cell Structure and Function
Notes
Discovery of the Cell:
•Mid 1600’s scientists began using
microscopes to observe living things
•Robert Hooke used microscope to
observe thin slice of cork—dead plant
material
Cork seemed to be made of boxlike chambers—Hooke called cells
•Anton van Leeuwenhoek discovered
living cells in pond water
Cell Theory:
• All living things composed of
cells
• Cells are the basic unit of
structure and function in
living things
• New cells are produced from
existing cells
Cell and its Environment:
•Organisms made of one
cell—unicellular organisms
Ex: bacteria
•Organisms made of many
cells—multicellular
organisms
Ex: plants, animals
• Each cell must be in “balance” with its
environment, exchange food, waste, H2O, CO2, O2
etc.
• Process by which organisms maintain a relatively
stable internal environment—homeostasis
Cell Parts and Functions
Find out what all the organelles in a
cell do and compare them to other
items using analogies.
Cell Parts / Organelles
• Organelle is a
fancy name for
specialized parts
of a cell. It means
“little organs”.
• Plant and animal
cells have many
organelles, most
of which they
have in common.
Animal and Plant Cell
Organelles in Common
• The following are organelles that both
plants and animals can have:
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Cell membrane
Nucleus
Nuclear membrane
Endoplasmic Reticulum
Ribosomes
Golgi Bodies
Vacuoles
Mitochondria
Chromatin
Cytoplasm
Organelles Vary by Cell
• Plants usually also have cell walls and
chloroplasts.
• Animals may also have cilia, flagella, and
lysosomes.
Cell Membrane
• All cells have a cell membrane.
• The cell membrane protects the contents of the cell and
regulates passage of materials into and out of the cell.
• The cell membrane is selectively permeable. This means that
small molecules can slip through easily and that larger
molecules are controlled as they pass in and out.
Cell membrane—determines what goes
in and out of the cell
Selectively Permeable
A Cell Membrane is like…
…your skin
because they both protect internal
parts and keep the whole together
Nucleus
• The nucleus has two major
functions: 1- it keeps all the
genetic material DNA; 2- it
controls all the functions in
the cell including growth,
metabolism, protein
synthesis, and reproduction
(cell division).
• Only the cells of advanced
organisms, known as
eukaryotes, have a
nucleus. Simpler one-celled
organisms (prokaryotes),
like the bacteria and
cyanobacteria, don't have a
nucleus. In these
organisms, all of the cell's
information is scattered
throughout the cytoplasm.
Nucleus—control center of the cell
•
Double membrane that surrounds the
nucleus—nuclear membrane
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Hereditary information inside the nucleus—
chromatin (DNA)
Cell Nucleus:
•Organisms that do NOT have a distinct nucleus—
prokaryotic (PRO rhymes with NO)
Ex: bacteria
•Organisms with cells that have true nucleus and
organelles—eukaryotic (EU rhymes with TRUE)
Ex: plants, animals, fungi
A Nucleus is like…
… your brain
because it controls your body like the
nucleus controls the cell.
Nuclear Membrane
• The nuclear membrane is
a double layer that holds
the nuclear material DNA
inside and regulates the
passage of materials into
and out of the nucleus.
• More than 20,000
ribosomes can be made
by the nucleus in a minute
and they need to be sent
out into the cytoplasm
through nuclear pores.
• The ER is connected to
the nuclear membrane.
A Nuclear Membrane is like…
… your skull
because it protects your brain like the
nuclear membrane protects the
nucleus.
Chromatin and Chromosomes
• Chromatin is made up of chromosomes, which
hold the genetic material: DNA!!!
Chromatin is like…
…your brain cells
because they are the genetic make up
of your brain just like the DNA is the
genetic make up of the cell.
Nucleolus
• The nucleolus is
inside the nucleus and
it is where the
ribosomes are made.
Nucleolus is like…
…your ???
because...
Endoplasmic Reticulum
• The endoplasmic reticulum
manufactures, processes,
and transports a wide
variety of biochemical
compounds for use inside
and outside of the cell.
• It also acts like a pipe
between the nucleus and the
cytoplasm.
• There are two types of ER,
rough ER (with ribosomes)
and smooth ER (without
ribosomes)
Rough Endoplasmic Reticulum (rough ER)—
makes and transports proteins within the
cell
•Called rough ER because of the
ribosomes found on its surface
Smooth Endoplasmic Reticulum
(smooth ER)—makes and transport
lipids and other materials within the cell
•Called smooth ER because no
ribosomes found on its surface
The Endoplasmic Reticulum is
like…
…your spinal cord
because it is a pathway from the brain
to the body which carries messages
just like the ER carries messages
from the nucleus to the cytoplasm.
Ribosomes
• Ribosomes are the protein
makers of the cell.
• Proteins are necessary for
all functions. They carry
the messages that tell
everything what to do and
build.
• Brain cells and pancreas
cell have the most
ribosomes because they
are constantly making
proteins.
Ribosomes—make proteins
The Ribosomes are like…
…individual cells
because they are responsible for
building up your body just like
ribosomes build up proteins.
Golgi Bodies
• The Golgi Bodies are often
considered the distribution
and shipping department for
the cell's chemical products.
• The Golgi Bodies modify
proteins and lipids (fats) that
have been built in the
endoplasmic reticulum and
prepare them for export
outside of the cell or for
transport to other locations
in the cell.
Golgi apparatus—processes and
packages proteins and other
substances produced in the ER
The Golgi Bodies are like…
…your digestive system
because it transports materials outside
the body like the golgi bodies
transport things outside the cell.
Vacuoles
• Vacuoles provide
structural support, storage
space, waste disposal, and
also help in protection
and growth.
• Plant cell vacuoles are
larger than animal cell
vacuoles, and help to
maintain the cell’s shape
and structure.
Vacuoles—sac-like structures for storage
•Plant cells usually contain a large vacuole
that fills most of the cell—pressure from this
large vacuole helps plants support
themselves
The Vacuoles are like…
…your fat cells
because they store excess material
and they provide the body with shape
just like the vacuoles do for the cell.
Mitochondria
• Mitochondria are the
“powerhouse” of the
cell. They convert
oxygen and nutrients
into adenosine
triphosphate (ATP).
• The process
mitochondria use to
make energy is called
respiration.
Mitochondria—energy source of the
cell (powerhouse)
The Mitochondria are like…
…your intestines
because they breakdown food to get
energy out of it just like the
mitochondria do to get ATP.
Cytoplasm
• The cytoplasm is a
jelly-like fluid that
surrounds and
cushions the
organelles in the cell.
• The cytoplasm also
helps the cell maintain
its shape.
Cytoplasm—gel-like medium that holds the
organelles in position
Cytoskeleton—network of protein
filaments (scaffolding) within the
cytoplasm that helps cell maintain its
shape
The Cytoplasm is like…
…your skeletal system
because it provides a structure and
support for all internal organs just
like cytoplasm provides a cushion
and support for the cell.
Lysosomes
• The main job of lysosomes
is to digest materials no
longer needed by the cell.
• The process of recycling the
cell's organic material is
known as autophagy.
Lysosomes break down
cellular waste products, fats,
carbohydrates, proteins,
and other macromolecules
into simple compounds,
which are then transferred
back into the cytoplasm as
new cell-building materials.
• Lysosomes are often made
from the membrane of the
golgi bodies.
Found in animal cells only:
Lysosomes—cleans up the cell and
digests unwanted materials
The Lysosomes are like…
…the stomach
because it uses acid to breakdown
materials just like the lysosomes
breakdown materials in the cell.
Cilia / Flagella
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Cilia and flagella are present in most microorganisms and animals,
but not in higher order plants.
The function of these parts is to allow for movement either of the cell
itself or of something past the cell.
Cilia
• The respiratory tract in
humans is lined with cilia
that keep inhaled dust,
smog, and potentially
harmful microorganisms
from entering the lungs.
Among other tasks, cilia
also generate water
currents to carry food and
oxygen past the gills of
clams and transport food
through the digestive
systems of snails.
Flagella
• Flagella are found primarily on gametes, but
create the water currents necessary for
respiration and circulation in sponges and
coelenterates as well.
Specialized Parts for movement:
Cilia (like little hairs)
Flagella (like a tail)
Pseudopodia
• Other forms of movements are seen with
pseudopodia “false feet” or lamellipodia
and filopodia – both projections of the
cytoskeleton used for movement.
• A white blood cell using pseudopods to
engulf a yeast cell.
Lamellipoda
used to move
this cell across
a surface.
The Cilia and Flagella are like…
… your arms and legs
because they allow for movement of
your body just like the cilia and
flagella allow for movement of the
cell.
Cell Wall
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The only plants have a cell wall which does many jobs:
It protects the cell contents.
It gives structure and rigidity to the plant.
It provides a porous medium for the circulation and distribution of
water, minerals, and other nutrients.
And it houses specialized molecules that regulate growth and
protect the plant from disease.
Found in plant cells only:
Cell wall—provides support and
protection for cell
•Composed mainly of cellulose (plant
starch)—fiber for our diet
The Cell Wall is like…
…the clothing you wear
because it surrounds and protects
your skin from the outside just like
the cell wall surrounds and protects
the cell membrane.
Chloroplast
• The chloroplast is
present only in plants
and some bacteria.
• The chloroplast has a
very important
function: it conducts
photosynthesis. This
means it traps sunlight
and uses it to help
make food.
Found in plant cells only:
Chloroplast—makes glucose using the
energy from the sun (photosynthesis)
The Chloroplast is like…
…your mouth
because it traps food to bring into
your body to be made into useable
energy just like the chloroplast traps
sunlight to bring into the cell to be
made into useable energy.
I think a ___ cell is like
the human body
Specialized Cells:
Different cells in your body do different jobs.
The structure (how it’s built) of cells matches
the function (what it does).
• Plant Examples:
1.Leaf cell—contains many
chloroplasts to maximize
photosynthesis
2.Root cell (potato)—
contains many vacuoles to
maximize water and starch
storage
• Animal Examples:
1. Epithelial cells—have villi to
increase nutrient absorption; found
in the intestines
2. Muscle cells—contain many
mitochondria to produce more
energy for movement
3. Nerve cells—have fibers called
dendrites that allow nerve cells to
communicate with each other
Your Turn!!!
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Now you get to make your own analogy.
First you will need to choose a plant cell or an animal cell.
Next you will need to list all the parts of the cell you chose.
After that you should pick something to compare your cell to,
like a car or a factory. Make an ANALOGY for each part of
the cell to each part of the item you chose. USE COMPLETE
SENTENCES TO EXPLAIN YOUR ANALOGY! For
example: A nucleus is like your brain because your brain
controls your body just like the nucleus controls the cell.
• Fourth you will make a rough sketch of your drawing and
show Miss Habdas your written analogies to get checked off.
• Finally you will make a beautiful poster of your “imitation
cell” and include all written analogies.
1st –Plant Cell or Animal Cell ???
2nd- List All Cell Parts
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cell membrane
nucleus
nuclear membrane
Etc….
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3 -
Compare Cell to ???
Make Analogies!!!
• A plant cell is like a car!!!
– The cell wall is like…
– The chloroplasts are like…
• An animal cell is like a
house!!!
– The lysosome is like…
– The cilia are like…
th
4 -
Make a Sketch &
Show Miss Habdas
th
5 -
Make a Beautiful
Cell Analogy Poster!!! 
• See all class examples.
YOU ARE DONE!!
The end 