Introduction
These three demos allow students to experience applications of knowledge of the digestive, respiratory, and circulatory systems by doing very short activities on themselves. They also allow the opportunity to discuss the pros and cons of using humans as test subjects. It is very useful for students to get the idea that scientific experiments do not have to be very complicated.
What happens?
- Digestive Enzymes – Salivary amylase breaks down the cracker.
- Control of Breathing – Students should be able to hold their breath for a shorter time period after hypoventilating into the bag, and for a longer time after hyperventilating.
- Baroreceptor Reflex – Pulse rates should be lowest for sitting rest, highest for just after standing, and medium for standing rest.