cells - basic unit of life
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What is a cell?
Cell is
The basic unit of life (of all living things).
The building blocks of life
Cells are constantly being damaged, but are
also constantly being replaced.
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What is a cell?
Living things that are made up of a SINGLE
CELLare called UNICELLULARor SINGLED-CELL
organisms.
Living things made up of MANY CELLSare
called MULTI CELLULARorganisms.
Cells multiply so that an organism can grow.
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Unicellular: Singled-Cell Organisms
In a singled-cell organism, a single cell
performs all vital activities such as feeding,
movement, respiration and reproduction.
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Examples of Singled-Cell Organisms
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Unicellular: Singled-Cell Organisms
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Multi Cellular Organisms
In multi cellular organisms, cells represent the
lowest level of organization. Other levels of
organization include tissues, organs and organ
system. The organ system get together to form
a complete organism.
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Organization of Cells in Multi Cellular
Organisms
Cellsare the basic unit of life.
Cells that work together to perform a specificjob in the body are called tissues.
A group of tissues that work together toperform a specific job are called organs.
Organs that work together in groups are called
organ systems. Organ systems come together to form an
organismthat can live on its own.
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Organization of Cells in Multi Cellular
Organisms
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What are cells like?
Cells come in different shapes and sizes.
Each cell performs a different task.
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Types of Cells
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Types of Cells
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Parts of a Cell
Cells have three parts:
The MEMBRANEis the part that covers around
the cell.
The NUCLEUSis the part which controls the cell.
The CYTOPLASMis the part that is between the
nucleus and the membrane.
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Animal Cell
Nucleus
Cytoplasm
Cell
Membrane
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Types of Animal Cells
Nerve cells carry messages between different
part of the body. Hence, they are elongated in
shape.
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Types of Animal Cells
Muscle cells help in movement through
contraction and expansion. Hence, they are
thin and long.
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Types of Animal Cells
Skin cells cover a large area. Hence, they are
flat in shape.
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Types of Animal Cells
Cheek cells
Nucleus
Cytoplasm
Cell
Membrane
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Types of Animal Cells
Red Blood Cells
White Blood Cells
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Types of Animal Cells
Bone cells make up the skeleton of
vertebrates.
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Plant Cells
Nucleus
Cytoplasm
Cell
Membrane
Chloroplasts
Cell Wall
Vacuole
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Types of Plant Cells
Onion cells NucleusCell
Membrane
Cell Wall
Cytoplasm
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Types of Plant Cells
Leaf cell
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Types of Plant Cells
Root cells
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Cell membrane
Nickname: The Barrier
Function : It is the outer most covering of a
cell. It is a partially permeablemembrane that controls what
goes in and out of the cell.
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Cell
Membrane
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Nucleus
Nickname: The Control Center
Function : It holds DNA. It is the brain of
the cell and directs all activitiesin the cell. It also controls the
growth and reproduction of the
cell.
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Nucleus
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Cytoplasm
Nickname: Jelly Belly
Function : It is a gel-like fluid inside a cell
that holds all the organelles in
the cell. Most activities and
chemical reactions take place
here.
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Cytoplasm
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Cell Wall
Nickname: The Supporter & Protector
Function: It supports the plant and holds it
upright. It protects the cell
membrane. It gives plant its
shape.
Only present in a plant cell
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Cell Wall
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Vacuole (Va-q-ol)
Nickname: The Refrigerator Function : It is a large storage that stores
water, nutrients and waste. It
helps to support the cell
structure.
Plant cells usually have one large vacuole while
animal cells may have many small vacuoles. Theyare found in the cytoplasm.
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Vacuole (Va-q-ol)
The vacuole stores most of the water in the
plant cell.
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Vacuole
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Chloroplast
Nickname: Green Bean Oven
Function : It contains green pigment called
chlorophyll (gives plant its green
colour). It traps energy from the
sun to allow plants to make food
through photosynthesis. Only present in plant cells.
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Sun
Energy
Chloroplast
CO2+
Water
Sugar+
Oxygen
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Chloroplasts
Chloroplasts
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Other Parts of a Cell
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Animal and Plant
CellsSimilarities & Differences
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Animal Cells
Animal cells have
Cell membrane
Cytoplasm
Nucleus
Many small vacuoles
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Plant Cells
Plant cells have
Cell wall
Cell membrane
Cytoplasm
Nucleus
Chloroplasts
One large vacuoles
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Lets compare!
Animal Cell
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Cell membrane
Cytoplasm
Nucleus
Many small vacuoles
Cell membrane
Cytoplasm
Nucleus
One large vacuole
Cell wall
Plant CellVS
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Know your Animal and Plant Cells!
Plant cell:
http://www.kscience.co.uk/resources/ks3/cell
s/plant_cell.swf
Animal cell:
http://www.kscience.co.uk/resources/ks3/cell
s/animal_cell.swf
Prepared by Miss Lee Y. H. (2014)
http://www.kscience.co.uk/resources/ks3/cells/plant_cell.swfhttp://www.kscience.co.uk/resources/ks3/cells/plant_cell.swfhttp://www.kscience.co.uk/resources/ks3/cells/animal_cell.swfhttp://www.kscience.co.uk/resources/ks3/cells/animal_cell.swfhttp://www.kscience.co.uk/resources/ks3/cells/animal_cell.swfhttp://www.kscience.co.uk/resources/ks3/cells/animal_cell.swfhttp://www.kscience.co.uk/resources/ks3/cells/animal_cell.swfhttp://www.kscience.co.uk/resources/ks3/cells/plant_cell.swfhttp://www.kscience.co.uk/resources/ks3/cells/plant_cell.swfhttp://www.kscience.co.uk/resources/ks3/cells/plant_cell.swf -
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Answer:
Through cell
division, new cells
will be produced to
replace and/orrepair the damaged
cells on the girls
knee.
The cut willheal as new
cells are
made during
cell division
The cut heals
because you wash
it with soap and
water and put a
band aide on it.
The cut will
heal because
new cells are
made during
budding.
The cut
will heal
because
the doctor
treats it.
How will
the Girlscut heal?
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Cell Division
Questions!
What is cell division?
What do cells do?
Why is it important to me?
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Producing New Cells
Cells increase in number by a process calledcell division.
The nucleus and the cytoplasm of a parent cell
divide to form two daughter cells. Eachdaughter cell divides further to form morecells.
Organisms are either single-celled or multi-celled. Both types of organisms undergo celldivision for different reasons.
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Cell Division
There are 2 types of cell division
Binary Fission
Budding (usually for single-celled organisms)
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Binary Fission
Binary Fission happens when a parent celldivides itself into 2 identical daughter cells.
Each of these daughter cells is identical to its
parent cells. Each daughter cell and grow and be able to
make a copy of its nucleus and divide into 2again.
As this process continues, many more cells areformed.
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Binary Fission
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Binary Fission
L di id ll h h bi fi i
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Task:
You are going to carry out a simpleactivity to show how cells divide tomake new ones.
1.Copy the table into your book.
2.Starting with one piece of paper,tear it in half.
3.How many pieces of paper do youhave now? Record this at stage B.
4.Now tear each of these pieces ofpaper in half and record how manypieces you have at stage C.
5.Repeat this process until youhave filled in your table.
StageNumber of
piecesA 1
B
C
D
E
F
G
H
Lets divide cells through binary fission
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Binary Fission
http://highered.mcgraw-
hill.com/sites/9834092339/student_view0/ch
apter10/animation_-_cell_division.html
http://global.britannica.com/EBchecked/topic
/65525/binary-fission
Prepared by Miss Lee Y. H. (2014)
http://highered.mcgraw-hill.com/sites/9834092339/student_view0/chapter10/animation_-_cell_division.htmlhttp://highered.mcgraw-hill.com/sites/9834092339/student_view0/chapter10/animation_-_cell_division.htmlhttp://highered.mcgraw-hill.com/sites/9834092339/student_view0/chapter10/animation_-_cell_division.htmlhttp://global.britannica.com/EBchecked/topic/65525/binary-fissionhttp://global.britannica.com/EBchecked/topic/65525/binary-fissionhttp://global.britannica.com/EBchecked/topic/65525/binary-fissionhttp://global.britannica.com/EBchecked/topic/65525/binary-fissionhttp://global.britannica.com/EBchecked/topic/65525/binary-fissionhttp://global.britannica.com/EBchecked/topic/65525/binary-fissionhttp://global.britannica.com/EBchecked/topic/65525/binary-fissionhttp://highered.mcgraw-hill.com/sites/9834092339/student_view0/chapter10/animation_-_cell_division.htmlhttp://highered.mcgraw-hill.com/sites/9834092339/student_view0/chapter10/animation_-_cell_division.htmlhttp://highered.mcgraw-hill.com/sites/9834092339/student_view0/chapter10/animation_-_cell_division.htmlhttp://highered.mcgraw-hill.com/sites/9834092339/student_view0/chapter10/animation_-_cell_division.htmlhttp://highered.mcgraw-hill.com/sites/9834092339/student_view0/chapter10/animation_-_cell_division.htmlhttp://highered.mcgraw-hill.com/sites/9834092339/student_view0/chapter10/animation_-_cell_division.htmlhttp://highered.mcgraw-hill.com/sites/9834092339/student_view0/chapter10/animation_-_cell_division.html -
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Budding Yeast is a microscopic fungus made up of only one cell.
They can increase in number by budding.
A bud forms on the outer surface of a parent cell.
The nucleus then doubles and divides.
One of the nuclei enters the bud. Then, a cell wall isformed between the parent cell and the bud.
Finally, the bud breaks away to become a new daughter
cell.
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Budding
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Budding
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Budding
http://www.youtube.com/watch?v=GQzntsCKnZc
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http://www.youtube.com/watch?v=GQzntsCKnZchttp://www.youtube.com/watch?v=GQzntsCKnZchttp://www.youtube.com/watch?v=GQzntsCKnZchttp://www.youtube.com/watch?v=GQzntsCKnZchttp://www.youtube.com/watch?v=GQzntsCKnZc -
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Lets compare
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Binary Fission Budding
Method One cell divides to form
two daughter cells of
almost equal size
Parent cell buds, forming
another, smaller daughter
cell.
Organism(s) Plants
Animals
Micro-organisms
Amoeba
Bacteria
Paramecium
Yeast
Function(s) Enables plants and
animals to grow Replaces old and
damaged cells
Reproduction in micro-
organisms
Reproduction of yeast.
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New cells need to be created For growth
Allow organisms to grow
To replace old/dead cells or repair damagedcells Replacing cells: Such as skin cells.
Repairing cells: Damaged tissues due to a fall isrepaired through cell division.
Cell regeneration (only if picture shows) Reproduction (for single-celled organisms)
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What is cell division important?
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Binary Fission
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Can we see cells?
YES WE CAN!
BUT only with the help
with a microscope.
We cannotsee cells with
our naked eyes.
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Copyright April 2013 Anh-Thi Tang (a.k.a. Tangstar Science)
PARTS OF THE COMPOUND LIGHT MICROSCOPE
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eyepiece
objective lenses
body tube
base
coarse adjustment knob
fine adjustment knob
stage
stage clips
diaphragm
arm
revolving nosepiece
light source / illuminator
condenser
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eye piece
objective lenses
body tube
base
coarse adjustment knob
fine adjustment knob
stage
stage clips
diaphragm
arm
revolving/rotating nosepiece
light source/illuminator
condenser
PARTS OF THE COMPOUND LIGHT MICROSCOPE
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Eyepiece
Contains a lens to _______ the image of the specimen.
The usual magnification is ___ X.
magnify
10
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Eyepiece
Contains a lens to _______ the image of the specimen.
The usual magnification is ___ X.
Some microscopes have ___ eyepiece.
magnify
10
two
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Body Tube
It ________ the eyepiece to the objective lenses.connects
It ensures the correct ________ of the microscope
components to correctly _____ the light from the
specimen into the viewers eye.
alignment
direct
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One ____ should be around the arm when _______ the
microscope (the other should be under the ____).
Arm
It ________ the body tube to the base.connects
hand carrying
base
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One ____ should be around the arm when _______ the
microscope (the other should be under the ____).
It ________ the body tube to the base.connects
hand carrying
Arm
base
PARTS OF THE COMPOUND LIGHT MICROSCOPE
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It contains the _________ and __________.
It ________ the weight of the microscope.
One hand should be _____ the base while _______ the
microscope (the other hand should be holding the
arm).
Base
supports
electronics
carrying
light source
under
PARTS OF THE COMPOUND LIGHT MICROSCOPE
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It contains the _________ and __________.
It ________ the weight of the microscope.
Base
supports
electronics light source
One hand should be _____ the base while _______ the
microscope (the other hand should be holding the
arm).
carryingunder
PARTS OF THE COMPOUND LIGHT MICROSCOPE
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Light Source / Illuminator
It sends light _______ through the _____________ and
through the ____ in the stage onto the ________ on theslide.
hole specimen
condenser lensupwards
PARTS OF THE COMPOUND LIGHT MICROSCOPE
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Light Source / Illuminator
It sends light _______ through the _____________ and
through the ____ in the stage onto the ________ on the
slide.
Older microscopes used to use ______ to ______ the
ambient light upwards.
hole specimencondenser lens
mirrors
upwards
mirror
reflect
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Revolving/Rotating Nose Piece
The _____________ are attached to it.
_______ the nose piece allows you to _____
between the different lenses.
objective lenses
Rotating switch
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Objective Lenses
These lenses further _______ the image of the
specimen.
magnify
The magnifications are usually ___ , ____ and ____ .4 X 10 X 40 X
4 X
10 X
40 X
There are usually __ lenses3
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Objective Lenses
These lenses further _______ the image of the
specimen.
magnify
There are usually __ lenses3 but some have __ lenses.4
The magnifications are usually ___ , ____ and ____ .4 X 10 X 40 X
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Objective Lenses
As the power increases, the magnification becomes _____, but the field of view (visible area) becomes _______.
largersmaller
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The ____ knob you should use, and always under ___
power. Never use it in ____ power.
Coarse Adjustment Knob
lowfirst
high
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The ____ knob you should use, and always under ___
power. Never use it in ____ power.
Both knobs move the _____ up and down to help put the
specimen in _____.focus
The ______ knob you should use under ______ power
for _____ focusing.
second higher
stage
Fine Adjustment Knob
lowfirsthigh
exact
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Some microscopes have the two knobs located
___________________.
Fine Adjustment Knob
one on top of the other
The smaller one on the bottom is always the ____
adjustment knob.
fine
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Stage
The stage is where you place the ____ which contains
the ________.
slidespecimen
It contains a ____ that allows ____ to pass through the
stage and onto the specimen.
hole light
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Stage Clips
The stage is where you place the ____ which contains
the ________.
slidespecimen
The stage clips ______ the slide on the stage.secure
It contains a ____ that allows ____ to pass through the
stage and onto the specimen.
hole light
PARTS OF THE COMPOUND LIGHT MICROSCOPE
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The lens under the stage that ___________
from the illuminator through to the ____ in
the stage.
focuses light
Condenser Lens
hole
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The lens under the stage that ___________
from the illuminator through to the ____ in
the stage.
focuses light
Diaphragm
hole
It contains a dial that rotates to _____ the _____________
that reaches the specimen.
adjust amount of light