1. Unit C: Cycling of Matter in Living Systems
Science 10
Unit C: Cycling of Matter in Living Systems

2. C1.1
Microscopy:
A Window
on a new
World

3. Aristotle Aristotle is known as “The Father of Biology.”
He was one of the first Greek philosophers who used the Scientific Method of observing, recording, reasoning, and interpreting in attempt to explain the world around him.

4. Microscopes Timeline 3000 years ago: Egypt & Mesopotamia
Glass – the material for lenses
Early 1200s: Roger Bacon
Described how crystal lenses might improve vision of the elderly

5. Microscopes Timeline Late 1200s: Salvino degli Amati (Italy)
Made the first pair of spectacles
Lenses were fashioned by craftsmen
A new branch of physics, called optics, was born to explain the movement of light

6. Microscopes Timeline 1600s: Telescopes & Microscopes
1595 Hans and Zacharias Janssen (Holland) invent the first 2-lens compound light microscope
1665 Robert Hooke (England) developed a 3-lens system.
Hooke observed thin slices of cork and saw what he called cells
1665 Antoni van Leeuwenhoek, an expert lens crafter was the first to reveal the microbial world
His daughter helped him make his microscopes
They were the first to see the movement of different types of cells we now call protozoa, sperm, and bacteria

8. Microscope by Hans and Zacharias Janssen

9. Figure C1.3 Hooke’s Mircroscope

10. Human Immunodeficiency Virus (HIV)
As lens technology improved over the years, the world’s knowledge of the microscopic world increased, allowing us to solve many problems
Red Blood Cells
Human Immunodeficiency Virus (HIV)
E. Coli bacteria cluser

11. Using Microscopes
A MICROSCOPE is an instrument with a lens or system of lenses for magnifying specimens.
In order to use a microscope you must be familiar with the following:
Microscope Structures & Functions
Microscope Handling Protocol
Calculating Magnification
Unit Conversion
Field of View

12. Eye Piece or Ocular Lens.
Coarse Focus Adjustment
Arm
Stage Clip
Fine Focus Adjustment
Base
Lamp
Diaphragm
Stage
Objective Lenses
Revolving Nosepiece
Body Tube

13. Handling A Microscope
Always carry the microscope in an upright position with two hands: one on the base, the other on the arm.
Use only lens paper to clean lenses.
Make sure the power switch is off before you plug it in.
Never allow the lens to touch the slide.
Never attempt to repair the microscope yourself.

14. Use stage clips to hold the slide steady.
Always start to focus on the low-power objective lens first.
Use the coarse focus first.
Never use the coarse focus on the high-power objective lens.
When you are finished:
Rotate to the low-power objective lens
Remove the slide
Turn the microscope off
Put the dust cover on
Remove the power cord from the socket by the plug.

15. Calculating Magnification
The MAGNIFICATION tells the reader how much larger (or smaller) the picture is than the real size of the item
In order to calculate the magnification of a system use the following formula:

16. Skill Practice
pg. 244 Calculating Magnification
What is the magnification if the following combinations of lenses are used?
a) A 2.5X low-power objective lens and a 10X ocular lens?
25X
b) A 100X high-power objective lens and a 10X ocular lens?
1000X

17. Equivalent Measurement
Unit Conversion
Line Master 1: Units of Measurement
Unit
Equivalent Measurement
Centimetre (cm)
1/100 metre; 10–2 m
Millimetre (mm)
1/10 centimetre; 10–3 m
Micrometre—also known as the Micron (μm)
1/1000 millimetre; 10–6 m
Nanometre (nm)
1/1000 micrometre; 10–9 m
Angstrom (Å)
1/10 nanometre; 10–10 m

18. Skill Practice Complete the following table. 40cm ______μm 1.6 nm
Unit Conversion
Complete the following table.
40cm
______μm
______ cm
1.6 nm
400 A
______ mm

19. Field of View
The FIELD OF VIEW is the entire area that you see when you look through the microscope.
Activity: Look at your partner through a paper towel roll. Now, get your partner to walk closer to you. Do you see more or less of your partner? Does your partner appear larger or smaller when he or she is closer to you? The same idea applies to magnification:
Magnification increases the size of what you see BUT decreases the amount of the object in view

20. Since the field of view decreases in size in direct proportion to the increase of the magnification, we can calculate the size of the other fields of view.
For example: If the field of view is 4000μ at 40X, it will be 10 times smaller at 400X, or 400μ in size.

21. Skill Practice Complete the following table: 4000 0.4 400
Calculating Field of View
Complete the following table:
Lens Magnification
Field of view (mm)
Field of view (μm) 40 4
100
1.6
1600
400
4000
0.4
400

22. Assignment Read pp. 242-246 Check & Reflect pg. 246 #1-8
Line Masters 1 & 2