The human eye may be only about the size of a ping-pong ball, but it is an amazingly complex sensory organ that requires all of its components to function properly in order for a person to have optimal vision. Each part of the eye works together with the others to process light rays into electrical impulses, or messages that are transmitted to the brain. The brain interprets this information and allows us to be aware of our surroundings. Our eyes and brain are able to capture and interpret millions of images a day, shaping our view of the world.
Although scientists do not fully understand the mechanism behind lightning, they think it is created when particles collide with other particles, causing them to generate and build up large amounts of static charges. The same basic process that creates lightning also occurs on a much smaller scale when you get a shock after shuffling across a carpet and touching a doorknob. What is giving you a shock is static electricity. In this set of activities, students will generate static electricity by rubbing or “charging” a balloon.
Bacteria are one-celled organisms that can only be seen under a microscope. There are thousands of kinds of bacteria, and they are found everywhere - in the air, in the depths of the ocean, in the human body and on human skin. Under favorable conditions, bacteria can multiply rapidly and form colonies (millions of bacterial cells grouped together) that can be observed with the naked eye. In this activity, students will formulate a hypothesis about which area of skin on their bodies may have the most or least amount or kinds of bacteria.
Many popular sports, including basketball, are based upon the use of a ball. Yet each type of ball is easily associated with a specific sport, because each ball is distinctly different. A ball’s performance is directly influenced by its characteristics or properties. For example, the oval shape of a football allows it to travel farther in the air than a ball that is round. In this activity, students will explore the properties of various balls from different sports, and discuss why the design of each ball is suited to its associated sport.
In this lesson, students will be amateur mycologists--collecting and analyzing various mushrooms. Through observation and discussion, students will gain knowledge of the basic anatomy of mushrooms, their life cycle, and their method of reproduction through spores. Students will learn to create spore prints of mushrooms and label and preserve their spore prints, just like a mycologist. Students also will learn that by comparing spore prints, they can identify different mushroom species.
Complex fluids are special kinds of mixtures that have characteristics of more than one phase of matter. In this video, the combination of cornstarch and water resulted in a substance that exhibited the properties of a solid and a liquid depending on the amount of pressure or force applied to it. These types of fluids that don’t behave like what we think of as “normal” fluids are called non-Newtonian fluids. Many non-Newtonian fluids are made of polymers, long chains of repeating molecules that give the fluid unusual physical properties such as flexibility and strength.