June 9, UNIT 2: Tissues, Organs & Systems of Living Things

June 9, Cell Theory & The Microscope

Cell Theory 1.All living things are composed of one or more cells.  Matthias Schleidan (1837)  all plants are made of cells  Theodor Schwann(1839)  all animals are made of cells

Cell Theory 2.Cells are the basic structural and functional units of life. – nothing smaller than a cell is considered to be alive – i.e. unicellular organisms are the smallest living things  bacteria  smallest living cells  protozoa  single-celled organisms

Cell Theory 3. All cells arise from the division of other cells

June 9, What can we see?

Zacharias Janssen and his father Hans of Holland in the 1590’s are credited with creating the first microscope Anthony van Leeuwenhoek, know as the “father” of the microscope and Robert Hooke made improvements by working on the lenses June 9, History Anthony van Leeuwenhoek Robert Hooke Zacharias Jansen

Compound Light Microscope

June 9, Parts of the Microscope Body Tube Revolving Nose Piece Objective Lenses Stage Clips Diaphragm Light Source Ocular Lens Arm Stage Coarse Adjustment knob Fine Adjustment knob Base Condenser

Revolving Nose Piece holds the objective lenses Diagram June 9,

Objective Lenses 2 nd set of magnifying lenses 4x, 10X or 40x Diagram June 9,

Stage Clips hold the slide in place Diagram June 9,

supports the slide Stage Diagram June 9,

diaphragm: controls the amount of light through the slide condenser narrows the beam of light through the slide Diaphragm & Condenser Turn to let more light in or to make dimmer. Diagram June 9,

Ocular Lens eyepiece contains a lens that magnifies10x Diagram June 9,

directs light up to ocular Body Tube Diagram June 9,

connects the microscope parts Arm Diagram June 9,

Adjustment Knob Coarse Focus Knob moves the stage up and down to focus the image Fine Focus Knob moves the stage SLIGHTLY to sharpen the image under high power Diagram June 9,

supports the microscope Base Diagram June 9,

Lamp Diagram June 9, light source sends light up through condenser

June 9, Compound Light Microscope 1. ocular 2. body tube 3. arm 4. stage clip adjustment knob 5. coarse adjustment knob 6. fine adjustment knob 7. revolving nosepiece 8. objective 9. aperture 10. stage clip 11. stage 12. condenser 13. diaphragm 14. light 15. base

Compound Light Microscope Microscope PartFunction 1. oculareyepiece lens, magnifies 10X 2. body tubedirects light into ocular, supports 3. armsupport 4. stage clip adjustment knob moves slide around 5. coarse adjustment knob moves stage up and down to focus image

Compound Light Microscope Microscope PartFunction 6. fine adjustment knob fine focus for most clear image 7. revolving nosepiece holds objective lenses & facilitates changing magnification 8. objective lensfurther magnifies the image 9. apertureopening to allow light to hit the specimen 10. stage clipholds slide in place

Compound Light Microscope Microscope PartFunction 11. stageplace specimen on it 12. condenserfocuses light into a beam 13. diaphragmcontrols the amount of light hitting the specimen 14. lightsends out light rays so specimen is visible 15. basesupports microscope

Field of view: diameter of the circle you see June 9, What do you see? 4mm approximately in low power

Compound Light Microscope magnification: - the ability of lenses to enlarge the image of a specimen resolution: - the amount of detail seen when viewing a specimen poor resolution = blurred image good resolution = clear, sharp image

Total Magnification 40x objective high power 10x objective medium power 4x objective low power June 9, total magnification = ocular lens x objective lens = 10 x objective total magnification: = 10 x 4 = 40X = 10 x 10 = 100X = 10 x 40 = 400X

Steps 1.Click nosepiece to the lowest power objective (4X) 2.Place the slide on the stage 3.Look into the eyepiece 4.Use the coarse adjustment knob to focus 5.Use stage clips only after having found & centered your slide around an area you want to examine 6.Turn the nosepiece to the higher power objective 7.Do NOT use the coarse focusing knob 8.Use the fine focus knob to sharpen the image June 9, Using the Microscope

Always carry with 2 hands: one on the arm and the other on the base Don’t bang it into other objects Make sure base is on a flat surface (only on black benches) Only use lens paper for cleaning Do not force knobs Carefully wrap cord around microscope June 9, Microscope Care

Homework Read page 7 – 14 Do page 14 # 2 – 4 Do page 15 # 1

Microscope Activity (Part 1) 1.Obtain a microscope. 2.Working in pairs, identify all of the parts of the microscope.

Microscope Activity (Part 2) 2.Do Resolution Activity Materials: compound light microscope slide & cover slip coloured picture from a magazine scissors

Microscope Activity (Part 2) 2.Resolution Activity a) Cut a small (1 cm x 1 cm) section of a colour image from a magazine. Include parts of the picture containing red, green, or blue colour. b) Place the section in the centre of a microscope slide and cover with a drop of water and a cover slip. c) Examine the image with a microscope under low, medium and high power. i) Describe the picture’s qualities (e.g. graininess, etc.) when observed with unaided eyes. ii) Describe the magnified images of the picture when examined under low, medium and high power. How do the qualities of the magnified images compare with the image viewed with unaided eyes. iii) Comment on the resolving abilities of your microscope.

Microscope Activity (Part 3) 3. Letter “e” Activity a) Cut out a lower case “e” from a magazine or news paper. b) Place the letter “e” in the centre of a microscope slide and cover with a drop of water and a cover slip. c) Center the wet-mount of the letter “e” on the stage with the “e” in its normal upright position. Bring the letter in to focus under low power. d) Note the position of the letter “e” on the slide (using your eyes only) and as seen through the eyepiece of the microscope. e) Draw the letter “e” as seen with your unaided eye and as seen through the microscope. Don’t forget to record the total magnification. f) While looking through the microscope, move the slide to the left, notice which way the letter “e” moved. Now move the slide to the right. Notice which way the letter “e” moved. Do the same with moving the slide away and towards you. g) Turn the medium power objective into position and bring the letter “e” into focus. Draw the letter as seen through the microscope. Don’t forget to record the total magnification. h) Looking at the slide, rotate the high power objective into position. Bring it into focus using the fine adjustment knob ONLY. Draw the letter “e” as it appears in the microscope and record the magnification.