Cells and Systems

Student Knowledge and Skills

WHAT YOU WILL LEARN BY THE END OF THIS UNIT:• List the main parts of a microscope• How a microscope works• The differences between plant and animal cells• The components of cells• The jobs performed by different plant and animal cells• The jobs performed by different tissues in animals and

plants.• How to make a wet mount and stain the mount• Make an accurate drawing of a cell.

• Scope of Unit:– The history of cell discovery– The microscope– The cell makeup– Plant Cells vs Animal Cells– Cells, tissues and organs– Melanomas– Bacteria, Fungi and Viruses

• What you will produce:– Workbook notes– Prac. Notes/reports– Cell drawings– Various Questions– CAI – microscope prac– There may be a final test

• Unicellular

• Multicellular

• Prokaryotes

• Eukaryotes

• Cell Membrane

• Cell Wall

• Cytosol

• Ribosome

KEY TERMS:

• Mitochondria

• Chloroplast

• Vacuole

• Nucleus

• Organelles

• Organs

• Cells

• Tissues

• Stem Cells

• Epidermis

• Cancer

• Melanoma

• Bacteria

• Algae

• Fungi

• Virus

Seeing Cells

• Microscopes enable us to see very small objects. There are many different types of microscopes. Light microscopes use a series of glass lenses to bend light to create a magnified image.

• Electron Microscopes use electrons to so display a magnified image on a screen

• http://www.telegraph.co.uk/science/picture-galleries/7924099/Creepy-crawlies-Amazing-Scanning-Electron-Microscope-pictures-of-insects-and-spiders.html?image=2

http://commtechlab.msu.edu/sites/dlc-me/zoo/zah0700.html

 Escherichia coliImage Width: 9.5 microns

http://www.art.com/products/p360992961-sa-i4012396/michael-gabridge-escherichia-coli-bacteria-colonies-on-macconkey-agar-culture-dish-lactose-fermenters-are-red.htm

http://janiceatmeredith.wordpress.com/2012/01/24/how-to-gram-stain/

History of the Microscope

• 1665 Robert Hooke named cells• 1675 Leeuwenhoek discovered bacteria• 1824 Dutrochet planets and animals are made of cells• 1831 Brown observes the nucleus• 1933 Ruska builds first electron microscope

Using a Microscope

Using a Microscope

• Always carry a microscope with 2 hands

• Only use lens cleaning tissue – not paper towel

• Look at the microscope side on, wind to the lowest point and then focus by winding upwards

Using The Microscope• Each lens has a magnification on it (the x number)• The total magnification is the eye piece x objective• Place a small piece of newsprint with the letter ‘e’ on a

glass slide.• Use a pipette to place a drop of water on the newsprint• Slowly lower a coverslip onto the print – try to avoid

bubbles• Place the slide onto the stage• Lower the bodytube to the lowest point• Look through the eyepiece and focus first using the

coarse then fine adjustment

Using the Microscope1. What do you notice about the letter?

2. Using low magnification draw what you see. Try to draw to scale.

3. Increase the magnification, don’t change the field of view and draw what you see.

4. Increase to the final magnification and draw what you see