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Lesson 1
Cells and
Reproduction
Lesson Starter- Using a
microscope
Why do scientists use microscopes?
They make images appear larger than
they actually are.
Microscope
Learning Intention:
o
I can accurately and safely use a microscope
to look at cells
Success Criteria:
Name the different parts of a microscope
Use a microscope to magnify objects on
microscope slides
o Know what magnification you are using in the
microscope.
o
o
Lesson Starter
1.
2.
3.
What piece of equipment do
scientists use to look at cells?
Why do they have to use this
piece of equipment?
Name as many parts of the piece
of equipment as possible
The Microscope
Lets name all the
Parts!!
Eyepiece
Objective
lenses
Fine focus
Handle
Clip
Stage
Rough focus
Light
The Microscope – What the parts
do?
Eyepiece To look at the
specimen
Further
Turret
magnifies the
Objective
specimen
lenses
Holds the slide
Clip
The slide is Stage
placed here
To illuminate the Light
specimen
Fine focus Makes the image
sharp
Handle
To carry the
microscope
Rough focus
To get a clear image
Using the Microscope
•Adjust the light to get a nice bright “Field
of View”.
•Clip the slide on the stage.
•Swing the low power lens into position.
•Bring the stage up close to the objective
lens with the rough focus.
•Looking into the eyepiece, adjust the focus
by moving the stage slowly downwards.
•Achieve a perfect image using the fine
focus.
•If you move up in magnification, you may
have to re-focus.
Microscope drawings must have:
Heading
o Pencil drawing of what YOU see
o Magnification
o Date
o
Slide #1: Paper hanky (prepared 22/01/07)
Magnification:
x100
Lesson Starter
1.
2.
When making drawings of slides
under the microscope what must
you include?
If the eyepiece lens is x10
magnification and the objective
lens is x40 magnification. What is
the total magnification?
Complete the table to identify what the
function of each part is:
Part of the microscope
Eye piece lens
Objective lenses
Stage
Stage clips
Rough/ fine focus
Function
Part of the
microscope
Eye piece lens
Function
Objective lenses
Magnifies the slide x10
Increases the size of the
object x4, x10, x40
Stage
Contains the slide to be viewed
Stage clips
Holds the slide in place
Allows the specimen to be
viewed in fine detail
Rough/ fine focus
Magnification

You can change the
magnification by
using other lenses.
For example
 Eyepiece magnification = x10
 Objective Lens magnification = x5

Total magnification = 5 x 10 = x50
Magnification calculations
Magnification: How many times bigger
the image appears.
Magnification Calculation
Total
Eyepiece
Objective
magnification = power
x lens power
Low power
Medium power
High power
Magnification
Low power
Name of slide: _____?
Date:
_____?
Magnification: _____?
Medium power
Name of slide: _____?
Date:
_____?
Magnification: _____?
Magnification calculations
Use the formula to complete the table.
Power
Low
Objective
Eyepiece
lens
Total
magnification magnification magnification
X10
x4
Medium
High
X10
x10
X100
X400
Estimating cell size
Question:
 What happens to the field of view as the
magnification increases?
 Low Power
Medium power
High power

20mm
10mm
5mm
Estimating cell size
Calculating cell size from the field of view
Count the number of cells across the diameter of the
field of view. Divide the number of cells by the width
of the field of view.
Lesson Starter- Estimating cell size
Question:
 The diameter of the field of view is 20mm
 The number of cells across the field of view is 4
 Estimate the size of one cell

20mm
Answer:
 If 4 cells measure 20mm.
=> one cell = 20/4 = 5mm

Learning intentions

Learn to prepare a microscope slide
Success Criteria
 Successfully prepare the slide.
 Successfully set up the microscope
and view the slide.
 Successfully focus the microscope and
examine the cells.
Preparing an onion slide
1.
2.
3.
4.
5.
Collect your microscope, light, slide, cover
slip, onion and iodine.
Place a small piece of onion onto the
middle of your slide.
Add a small drop of iodine on top of the
onion. This helps to stain the cell’s
structures.
Cover the piece of onion with a cover slip.
Look at your slide under the microscope.
Onion cells under the microscope
What can you see?
Make a drawing of
what you see in
pencil.
Make sure you add in
all the different
features!
A Typical Plant Cell
vacuole
nucleus
cell membrane
cell wall
green
chloroplast
cytoplasm
Lesson starter- Label the Parts of
the Microscope
Stage
Base
A
Eyepiece Lens
Focus control
D
Objective Lens
mirror
C
Objective Lens control
B
Handle
Lesson Starter
1.
2.
If you are using a microscope to view
cells and you have set the objective
lens to x350. What would the total
magnification be?
Name the 6 cell structures found in
plant cells
Learning intentions

Learn to prepare a microscope slide of
an animal cell.
Success Criteria
 I can successfully prepare the slide.
 I can successfully focus the
microscope and view the animal cell
(cheek cells)
Preparing a cheek slide
1.
2.
3.
4.
5.
Collect your microscope, light, slide, cover
slip, cotton bud and eosin stain.
Firmly rub the cotton bud on the inside of
your cheek.
Take the bud gently sweep it onto the
slide. Add a small drop of eosin on top of
the cheek cells.
Cover the cheek cells with a cover slip.
Look at your slide under the microscope.
Cheek cells under the microscope
What can you see?
Make a drawing of
what you see in
pencil.
Make sure you add in
all the different
features!
Learning intentions

Learn to prepare a microscope slide of
an animal cell.
Success Criteria
 I can successfully prepare the slide.
 I can successfully focus the
microscope and view the animal cell
(cheek cells)
Cells
Cells
What you should know:
 State that cells are the basic units of life
 Understand the difference between unicells
and multi cells
 Identify the structures in a plant and animal
cell.
Experimental activity:
Using a microscope
Lesson Starter
1.
2.
3.
Draw an animal cell and label the
features
What extra three structures are
found in a plant cell?
Can you describe the functions of any
of these features
What are cells?

Cells are the basic unit of life.

All living organisms are made up of one or more cells

Cells are very small
Unicellular organisms

1. Unicellular organisms

A living thing made of only ONE cell

Examples: Protozoa, bacteria and some algae
Multicellular Organisms
Multicellular organism:
Living thing made up of
more than one cell
Examples:
Animals,
Plants
Humans (have over
10 trillion cells)
Cells
Lesson Starter- animal cell
Cell
membrane
nucleus
Cytoplasm
Lesson Starter- plant cell
vacuole
nucleus
chloroplasts
Cell membrane
Cell wall
cytoplasm
Cell1-6
Plant Cell
Name Animal
structures
Nucleus
Chloroplast
1._____________________
4._________________________
Cytoplasm
Vacuole
2._____________________
5._________________________
3._____________________
6._________________________
Cell membrane
Cell wall
Common cell structures: Summary of plants and animal cells
Plant and animal cells both have Only plant cells have
Nucleus
Cytoplasm
Cell membrane
Chloroplast
Vacuole
Cell wall
Cells
Most cells are transparent.
 To see the detailed structure of a cell it must be
stained and viewed under a microscope.
Stain for an animal cell
Stain for a plant cell
Eosin stain
Iodine solution

Animal cell: Made of 3 parts
Cell part Structure & Function
Thin flexible membrane
Cell
surrounding a cell. Controls
membrane entry and exit of materials.
Cytoplasm
Transparent material inside
the cell. Site of biochemical
reactions in the cell.
Nucleus
Structure that contains
chromosomes.
Controls the cell activities.
Animal cell structures
Name
Function
Cell membrane
Controls which substances can enter
and leave the cell
Cytoplasm
Site of biochemical reactions
Nucleus
Controls all cell activities
Plant cell: Made of 6 parts
Cell part Structure & Function
Thin flexible membrane
Cell
surrounding cell. Controls
membrane entry and exit of materials.
Nucleus
Cytoplasm
Vacuole
Chloroplast
Cell wall
Structure that contains
chromosomes.
Controls cell activities.
Transparent material inside
the cell. Site of biochemical
reactions in the cell.
Supports the plant cell.
Contains water, sugar & salts
Green disc structure
containing chlorophyll.
Site of photosynthesis.
Slightly flexible boundary
that maintains cell shape.
Plant cell structures
Name
Function
Cell Wall
Gives cell its rigid shape and
supports the cell
Chloroplast
Site of photosynthesis.
Contains chlorophyll (green
pigment which helps the plant
make its own food)
Vacuole
Contains cell sap (sugars and
salts)
Cell
membrane
Controls which substances can
enter and leave the cell
Cytoplasm
Site of biochemical reactions
Nucleus
Controls all cell activities
Identifying cells
Animal cell OR Plant cell ?
Egg
cell
Identifying cells
Animal cell OR Plant cell ?
Plant
cells
Identifying cells
Animal cell OR Plant cell ?
Nerve
cell
Identifying cells
Animal cell OR Plant cell ?
Epithelial Cell from an onion
Identifying cells
Animal cell OR Plant cell ?
Red blood
cell
Plant or Animal Cell?
Animal cell OR Plant cell ?
Plant
cell
Identifying cells
Animal cell OR Plant cell ?
Sperm
cell
Animal cells
Plant Cells
Lesson Starter- Identifying cells
Animal cell OR Plant cell ?
Specialised cells for special jobs
Animal and plant cells have the same basic structures but
have different shapes to allow them to specialise for
different jobs.
Cell type Diagram
Nerve
Sperm
Egg
Root
Structure/ Function
Special Cells for Special Jobs
Red blood cells
carry oxygen
round the body.
White cells fight
diseases in the
body.
Muscle cells

Different muscle
cells have different
jobs to do in the
body
Nerve cells
The long thin fibres carry messages
from one part of the body to another
Special cells for special jobs

Male sex cells
(sperm) have a
streamlined shape

This helps them
swim to female egg
to fertilise it
Special cells for special jobs

Female sex cell (egg)

The egg cell is larger
than the sperm
because it contains a
food store, needed
for energy should
the egg be fertilised
by a sperm.
Special cells for special jobs

Root cell

Hairs to increase the surface area
for water uptake
Cell
type
Diagram
Structure/ Function
Nerve
Long, thin fibres to carry messages
from one part of the body to another
Sperm
Streamlined shape and a tail to help
them to swim to the egg cell
Egg
Large cell, containing a food source
for energy
Root
Hairs to increase the surface area for
water uptake
Special Cells for Special
Jobs
• Use Starting Science Book 1 P76
•Choose three cells, draw each of them and
say how each is suited to the job it does.
A Tissue
Where we have a group of similar
cells all working together, we call
this a tissue
Finally….Organising cells
Complex
Organism
System
Simple
All the systems working
together as a coordinated
living unit
A group of organs cooperating to a common
purpose
Organ
Different tissues
working together
Tissue
Cells of the same type
grouped together
Cell
The basic unit of life