Transcript Plant Cell

Unit 4/Ch. 7
Cells
Introduction to Cells
and
the Cell Theory
Discovery of the Cell
They look
like tiny
empty
rooms!
Robert Hook (1665)
Was the first
to see
cells…cork
cells that is!
Antwon Van Leeuwenhoek (1674)
First to see
living cells!
I saw tiny
moving things!
They must be
alive!
Matthias Schleiden (1839)
All plants
are made
of cells!
German Botanist
Theodore Schwann (1839)
German Zoologist
All animals
are made
of cells!
Rudolf Virchow (1855)
Stated that cells come from preexisting cells. (Living things
come from other living things!)
The Cell Theory
• All living things are composed of cells.
• Cells are the basic units of life.
• New cells come from existing cells.
Exploring Cells using
Microscopes
Purpose is to see a variety of
cells and the differences.
The Compound light Microscope
• Light passes through
specimen
• Can be used to
observe living things
• Can’t be used to
observe molecules or
viruses
Image from: www. Biologycorner.com
Light microscope image of amoeba
Magnified
100x
Light microscope image of cheek
cells
Scanning Electron Microscope
(SEM)
• Beam of electrons scan
surface of specimen
• 3-D image
• Views only dead
specimen
SEM image of housefly
SEM of spider
Total Magnification
=
Eyepiece x Objective
Prokaryotes and
Eukaryotes
Notes
Prokaryotes
•
•
•
•
•
•
Small
Simplest
Evolved first
Less Complex
Genetic material (DNA) NOT contained in a nucleus
Example: Bacteria cells
Eukaryotes
• Larger
• More complex
• Membrane bound
structures
• Genetic material is in a
nucleus
• Examples Include:
protist, fungi, plant, and
animal cells
Image from: www.daviddarling.info/images/cell_structure.jpg
Prokaryotes and Eukaryotes
• Both
•
•
•
•
Cell membrane
Ribosomes
Cytoplasm
DNA & RNA
• Prokaryotes have circular DNA called
plasmids
• Eukaryotes have DNA in the Nucleus
Prokaryote & Eukaryote Size
Comparison
Prokaryotic cells are smaller than Eukaryotic cells.
Image from: www.phschool.com/.../images/cells/allcell.jpg
Exit Ticket
1. How is the total magnification power of a
light microscope determined?
2. List the three parts of the cell theory.
3. What structure is found in eukaryotic cells
that is not found in prokaryotic cells?
4. Give an example of a prokaryotic and a
eukaryotic cell.
5. Name three things that ALL cells have.
Prokaryote and Eukaryote
Drawings
Draw, Color, Label and Descriptions
Figure 7.2 A & B and Size Comparison Chart,
Page 174
Write the Questions and Answers
1.Which is larger in size? (prokaryote/eukaryote)
2.Define prokaryote and eukaryote.
3.List 2 things they have in common.
4.List 2 differences they have.
Cell Parts and Functions
Prokaryote & Eukaryote Recap
• Prokaryote---No true nucleus, smaller than
eukaryotes, simple, no membrane bound
organelles, circular DNA strands called plasmids,
example: bacteria
• Eukaryote--- True nucleus, larger than
prokaryotes, complex, membrane bound
organelles, DNA found in nucleus, example:
plant and animal cells
• Both---Ribosomes, DNA/RNA, cytoplasm, cell
membrane
Organelles
“little organs”
• Specialized structures inside EUKARYOTIC cells
– each structure has a job to do
They’re like
mini-organs!
Model Animal Cell
Cytoplasm
“Jello”
• Gel-like substance
holds the organelles
in place
Image from: www.cs.utexas.edu
Cell membrane
“Gatekeeper”
phosphate
“head”
• Function
– separates cell from outside
– Maintains homeostasis (semi-permeable)
– controls what enters or leaves cell
– recognizes signals from other cells
• allows communication between cells
• Structure (lipids & proteins)
– double layer of fat
• phospholipid bilayer
• proteins
lipid “tail”
Nucleus
“Brain”
Contains cell’s DNA in the form of chromatin
•
• Chromatin forms chromosomes during cell division
• Surrounded by nuclear envelope
• Contains small dense nucleolus (Site of Ribosome Synthesis)
Nuclear
envelope
nucleolus
Image from: www.cs.utexas.edu/.../src/images/nucleus.jpg
Ribosomes
“Protein Factory”
• Site of Protein Synthesis
Image from: Genetics Education, Murdoch Children's Medical Research Institute
Endoplasmic Reticulum
“Transportation System”
• Rough ER – studded
with ribosomes
– Makes and transports
lipids and proteins
• Smooth ER – no
ribosomes
– Contains enzymes which
make lipids
GOLGI BODY
(APPARATUS/COMPLEX)
“Post Office”
• Pancakelike
membrane
stacks
•Sorts, and packages
proteins for transport
out of cell
LYSOSOMES
“Garbage Disposal”
• Membrane bound
sacs that contain
digestive enzymes.
•They digest food or get
rid of unwanted cell
parts.
www.emc.maricopa.edu/.../BIOBK/lysosomes.gif
Vacuoles
“Storage”
• Saclike structures that
store water and other
materials
• Large central vacuole in
plants
• Contractile vacuole in
single-celled organisms
(paramecium)
Image from: Benjamin Cummins Inc.
Mitochondria
“Powerhouse”
• Converts chemical energy
in food into a useable form
for the cell. (ATP)
• Contains its own DNA
• Cristae (folded inner
membrane) INCREASES
SURFACE AREA FOR
ENERGY PRODUCTION
DURING AEROBIC
CELLULAR RESPIRATION
Mitochondria are in both cells!!
animal cells
plant cells
mitochondria
chloroplast
Chloroplast
“Photosynthesis”
• Capture solar energy and converts it into chemical energy
(Glucose) during photosynthesis
• Found in plant cells
• Contains its own DNA
CELL WALL
“Support/Protect”
•Outside of cell membrane.
•Found in plant, algae, fungi, and
prokaryotic cells.
•Plant cell walls made of cellulose.
PLANT CELLS
• Cell wall
• Chloroplasts
• Bigger
vacuoles
• No centrioles
Proteins do all the work!
one of the major job of cells is to make proteins,
because…
proteins do all the work!
structural
enzymes
signals
proteins
DNA
receptors
cells
DNA codes for proteins which are assembled by the
ribosomes and used as
enzymes for energy production at the mitochondria.
nucleus
control cell
protects DNA
cytoplasm
jelly-like material
around organelles
ribosomes
make proteins
central vacuole
storage: food,
water or waste
mitochondria
make ATP in
cellular respiration
cell membrane
cell boundary
controls movement
of materials in & out
recognizes signals
cell wall
support
chloroplast
make ATP & sugars in
photosynthesis
PLANT CELLS
• Cell wall
• Chloroplasts
• Bigger
vacuoles
• No centrioles
What structures do Animal Cells lack? Plant cells?
Exit Ticket
1. What cell organelle in an animal cell is
responsible for maintaining homeostasis?
2. What is the primary function of a plant cell’s
vacuole?
3. What two organic molecules make up the cell
membrane?
4. What organelle in the cell is the site of protein
synthesis?
5. What is the primary function of cytoplasm in
plant and animal cells?
Give Me 5
Plant Cell & Animal Cell
• Directions: Trace your hand, using a pencil, on the sheet of
paper provided and cut it out. One side will be for a Plant Cell
and the other side will be for an Animal Cell. On each
finger(5), write one of the organelles listed and give its
function. Draw each organelle in the palm of each hand to
create a cell.
• Be creative and color each side.
• Organelles:
• Plant Cell – Cell Wall, Nucleus, Mitochondria, Cytoplasm,
Large Vacuole, Chloroplast, Endoplasmic Reticulum
• Animal Cell – Nucleus, Mitochondria, Cytoplasm, Vacuole,
Cell Membrane, Centrioles, Lysosomes
An example is on the board
This will be a project Grade
Specialized Cells Notes
Where do you think cells are located in our body?
– EVERYWHERE!!!
– Humans are made up of cells that work together and
build muscle, bones, skin, and other organs.
• All living things are made of building blocks
called CELLS.
• Humans, plants, animals, and bacteria are
made up of one or many cells.
Cells are incredibly small – so small that
microscopes are needed to magnify them
so that we can see them.
Specialized Cells
• 50 – 75 Trillion cells in
your body
• 220 specialized cells
– Heart
– Nerve
– Blood
– Sperm
– Etc.
• Why different?
Specialized Cell
• A cell that has a particular structure and
performs a specific function
• Each type has unique shape, size and
features allowing it to do its job accurately
Cell Differentiation
• All cells begin undifferentiated/nonspecialized
• Differentiation: specific parts of DNA are
activated “turned on”;
• Parts of DNA that are activated determine
the function and specialized structure of a
cell
• All cells in an organism contain the same
DNA
Specialized Cells
• The cells in animals are not all identical.
• They perform specific functions, such as delivering
oxygen and fighting disease, moving the skeleton,
storing energy or coordinating the whole body.
Plant cells also have a variety of specialized
cells. Cells in the leaf of a tree have a different
structure and function from the cells in the trunk.
Example:
Trachea Cilia
(don’t copy into notes)
• Specialized cells have physical and chemical differences that
allow each type to perform one job very well.
• These cells help keep dirt out of the lungs.
– The orange goblet cells secrete mucus
– The hair-like extensions (called cilia) move the mucus along the
trachea to remove inhaled dust and dirt.
Ear Cells (Do Not Write in Your Notes)
– have cilia – tiny hairs on inner ear cells that pick up
vibrations in the air and send signal to brain.
Examples:
1. Red Blood Cell
– Round edges to travel in blood vessels easier
– No nucleus = more room to carry O2 and CO2
Red Blood Cells
2. Leukocytes (White Blood Cells-WBC)
– Defends the body against both infections,
diseases, and foreign materials.
White Blood Cells
3. Sperm Cells
Head contains enzymes & nucleus
Designed to Fertilise eggs.
Found in the Testes
Tail
A sperm is small and has a
long tail that provides
movement so it can swim
and find an egg cell.
The head contains enzymes
which allow it to digest into an
egg cell and join with it.
Sperm Cells
4. Nerve Cell
– Long, skinny arms to send messages
quickly over long distances
The Nerve Cell
5. Muscle Cell
– Long, skinny cells that lengthen and shorten to
move muscles
Muscle Cells
6. Fat Cells
– stores fat droplets in the bulk of their volume
for use as energy
Fat Cells
7. Bone Cells
– gives strength, support, and framework to the
body by forming the skeletal system
Bone Cells
Review
• 1: All living things are made of cells.
• 2: Cells are very small.
• 3: Cells divide and make more cells to help us
grow.
• 4: All cells have the same basic parts to do
specific tasks.
• 5: There are many different types of cells in our
body doing many different jobs.
• 6: Cells form organs, which form organ systems.
Attach the Chart in your Notebook
Add COLOR
Exit Ticket
1. Approximately how many cells make up the human
body?
2. Which cells do not have a nucleus and this allows
the cells room to carry more CO2 and O2?
3. Which cells have long, skinny arms to send
messages quickly over long distances?
4. (True/False) All cells begin undifferentiated.
5. (True/False) All cells in an organism contain the
same DNA.
Stem Cells
• Unspecialized cells that divide quickly and
do not have a particular function yet.
Only stem cells can differentiate into one or
more types of specialized cells.
Where are Stem Cells?
Embryonic Cells
• Have not yet differentiated into various cell
types are called embryonic stem cells.
Stem cells found in organisms, for instance
in bone marrow, are called adult stem cells.
Scientist have recently demonstrated that
stem cells, both embryonic and adult, with
the right laboratory culture conditions,
differentiate into specialized cells.
Cord Blood Cell Banking?
• The blood found in an umbilical
cord immediately after the birth
of a child is a rich source of
stem cells.
• These stem cells can develop
into various kinds of blood
cells.
• The blood collected from the
cord can be banked (or stored)
in the event it is needed later in
the child’s or a sibling’s life.
How can Stem Cells be Used?
• For diseases such as leukemia,
stem cells collected from healthy
blood can be injected into a
patient’s blood after the diseased
cells have been killed.
• The healthy cells then grow in
the patient’s bone marrow and
produce healthy, cancer-free
blood cells.
•
http://www.dnalc.org/resources/animations/stemcells.html
•
http://youtu.be/O5r-T6ANKto
Attach the Chart in your Notebook
Do the Current
Research on the
bottom of your
notes.
Exit Ticket
1. What are stem cells?
2. Where are adult stem cells found in the body?
3. (True/False) Stem cells can develop into any type
of cell.
4. What determines the type of cell that an
unspecialized cell will become?
5. Name one place embryonic cells are found.
Specialized CellsDrawings
Draw, Color, Label and Descriptions.
Write the Questions and Answers.
Paramecium: Figure 19.5, Page 507
1. A pair of ___ ___ pump out excess water.
2. Paramecium are (unicellular/multicellular).
3. Paramecium can move by beating its ___.
Amoeba: Figure 19.2 A, B & C, Page 505
1. What does a pseudopod mean?
2. Explain how an Amoeba eats.
3. In which organelle does photosynthesis occur?
Euglena: Figure 19.8, Page 511
1. What is the purpose of an eyespot?
2. Which organelle is used by the Euglena to photosynthesis?