Why should we wash our hands?
October 3, 2012 | By Mrs D Arding | Impressions: 12 |
More from Mrs D Arding
COW’S EYE dissection page 2 Here’s what you need: - One cow’s eye for every two participants - One single-edged razor blade or scalpel for every two participants - Scissors (optional) - Wax paper and paper towels - Plastic garbage bag - A cutting board or other surface on which you can cut - A sheet of newspaper - Soap, water, and paper towels for cleaning up Here’s where to get cows’ eyes: You can order cows’ eyes at a butcher shop or purchase them directly from a slaughterhouse. Try to get eyes with the muscles and fat still attached. If possible pick up the cows’ eyes the day of the dissection; eyes are easier to cut when they are fresh. This diagram shows the parts of the eye. Can you nd these parts in a cow’s eye? SCLERATAPETUM OPTIC NERVE BLIND SPOT VITREOUS HUMOR LENS IRIS CORNEA RETINA AQUEOUS HUMOR PUPIL
What is a force? • Forces are what makes things move, like a push or a pull. • When you kick a football your foot applies a force to the ball. • The engine of a train uses a pulling force to make the carriages move along the track. • These are mechanical contact forces.