People are usually able to have children before they are able to care for them properly. Following discussions of sounds and the effects on hearing, students research and report on hearing aids. Students focus on why people need them and how they work. The undigestible parts of food are eliminated. By breathing, people take in the oxygen they need to live.
Skin protects the body from harmful substances and other organisms and from drying out.
The brain gets signals from all parts of the body telling what is going on there. The brain also sends signals to parts of the body to influence what they do. Human beings can use the memory of their past experiences to make judgments about new situations. Many skills can be practiced until they become automatic. If the right skills are practiced, performance may improve.