Download Cell and The Microscope

Cell and The Microscope
Animal cell
Nucleus: control centre of the cell (contains genes)
Cell membrane: allows things to pass in
and out of cell
Cytoplasm: watery fluid in the cell
Plant cell
Chloroplasts: allows photosynthesis to occur
Cell wall: protects the cell
Vacuole: stores food
Differences between plant cells and
animal cells:
Plant cell
Have cell wall
Animal cell
No cell wall
Have chloroplast
No chloroplast
Have vacuole
No vacuole
The Microscope
Parts of the Microscope:
Eyepiece lens: magnifies the image
Coarse focus knob: roughly focuses the image
Fine focus knob: allows for precise focus
Nosepiece: allows to move the different objective lens
Objective lens: magnifies the image
NOTE: Eyepiece lens = x10
Objective lens: x 40
Total magnification: x 400
Parts of the microscope:
Stage: slide is place onto the stage
Mirror: reflects light up through the slide
How to use a microscope:
1) Place the slide on the stage.
2) Turn on the light source.
3) Place clip on slide to hold it in position.
4) Use the coarse focus knob to place lens over the slide and
move it up and down to focus the slide.
5) Adjust the light by using the condenser and the diaphragm.
6) Now use the fine focus knob to better focus your slide.
To prepare a slide from a plant tissue and view
it under a microscope:
Equipment: onion, microscope slide, iodine
solution, tissue paper, microscope.
Method:
1) Use forceps to pull a strip of thin, transparent epidermis
from an inner leaf.
2) Place a small piece of the strip on the slide.
3) Add iodine (stains the nucleus and shows the membranes
clearly).
4) Add a few drops of water (prevents cell from drying out).
5) Add a coverslip at an angle (protects the lens and
eliminates air bubbles).
Results:
Preparing an animal cell
Examining an animal cell
Cells, tissues and organs
• Cells do not work alone in living things.
• Tissues are a group of similar cells which carry
out the same function.
Example: muscles, red blood cells
Organs
• Organs are a structure that contains two or more tissues
working together.
Examples in animals: lungs, kidneys, brain
Examples in plants: roots, leaves, flowers
Systems
• A number of organs working together.
Breathing system
Digestive system
Summary
Cells
Tissues
Organs
Systems
Organisms