Quick Quiz Write down the letter(s) which answer the questions asked All cell types Animal Plant Fungal Bacterial 1. Which cells contain ribosomes? 2. Which cells contain plasmids? 3. Which cells contain vacuoles? 4. Which cells contain a cell wall made of cellulose? 5. Which cells have mitochondria?
Quick Quiz Write down the letter(s) which answer the questions asked Plasmid Ribosome Nucleus 6. Site of aerobic respiration? 7. Site of protein synthesis? 8. Controls cell activities? 9. Site of photosynthesis? 10. Only found in bacterial cells?
National 5 Cell Biology Viewing Cells
We are learning to: Describe how to use a light microscope to view cell samples Explain the use of stains when viewing cells through a light microscope Select a suitable stain to view different cells under a light microscope Calculate cell length and breadth when viewed through a microscope
What I'm looking for: Focus microscope onto a prepared slide to view different cells Prepared slide of cheek and onion cell Drawing of cells as viewed through a microscope Calculate cell size
Viewing Cells Watch the video “How to use a microscope”
Viewing Cells Collect Microscope 2 slides 2 coverslips Cotton bud Tweezers Stains Dropper Onion sample
Rub cotton bud against inside of your cheek Method Rub cotton bud against inside of your cheek Rub cotton bud against slide Put a drop of Methylene blue stain on a slide Place a cover slip on the drop of stain, lowering it gently using the cotton bud Observe your cells under a microscope Draw a diagram in your jotter Using a similar procedure make slides of different cells. Safety Cautions PLACE ALL COTTON BUDS IN WASTE BEAKER. DO NOT HANDLE ANY COTTON BUDS OR SLIDES OTHER THAN YOUR OWN!! BE CAREFUL – METHYLENE BLUE CAN STAIN CLOTHES!! SLIDES ARE MADE FROM THIN GLASS. TAKE CARE WHEN HANDLING
Cheek cells
Elodea
Red onion cells Yeast cells
Stains Cells are viewed using a microscope Stains must be added to view the parts of a cell clearly __________ solution used for plant cells ____________ ____ used for animal cells IODINE METHYLENE BLUE
Total Magnification Eyepiece Lens Objective Lens
Eyepiece Objective Magnification Actual Size Apparent size 10x 100x 0.1mm 10mm 5x 20x 0.01mm 50x 5mm 800x 0.02mm 30x 900x 0.001mm 400x 0.04mm
Eyepiece Objective Magnification Actual Size Apparent size 10x 100x 0.1mm 10mm 5x 20x 0.01mm 1mm 50x 500x 5mm 40x 800x 0.02mm 16mm 30x 900x 0.001mm 0.9mm 400x 0.0001mm 0.04mm
Calculating cell size THINK! How could you calculate the average length of theses cells?
Calculating cell size Find out the average cell length and breadth 5 cells across 2mm 2/5 = 0.4mm Average cell breadth 10 cells across 2mm 2/10 = 0.2mm 2mm
I can: Describe how to use a light microscope to view cell samples Explain the use of stains when viewing cells through a light microscope Select a suitable stain to view different cells under a light microscope Calculate cell length and breadth when viewed through a microscope