(This outline may be introduced with Plant Biology, or, better, may come as application of the work in Second-term Biology.)
The Environment. Changes for betterment under control. How a city boy may improve his environment: by proper clothing, proper food and preparation of food, by care in home life; by sanitary conditions in neighborhood and in home.
Review of Activities of Cell. Irritability, food taking, assimilation, oxidation, excretion, reproduction. Similarity of functions of plant and animal cells. All cells perform these functions. Some cells perform functions especially well, e.g. contracting muscle cells. All cells need food and oxygen. Some must have this carried to them. A system of tubes carries blood which carries food and oxygen. Food must be prepared to get into the blood. Digestive system: mouth, teeth, stomach, intestines, glands, and digestive juices. Uses of above in preparing food to pass into the blood. Absorption of food into the blood. How oxygen gets to the cells. Nose, throat, windpipe, lungs; blood goes to lungs and carries away oxygen. Excretion. Cells give up wastes to blood and these wastes taken out of blood by kidneys and other glands and passed out of body. Sweat, urine, carbon dioxide.
Certain Kinds of Work performed by Certain Kinds of Cells. Advantage of this. Cells of movement. Muscles, tissues. Bones as levers necessary for some movements. This especially true for legs and arms. Skeleton also necessary for protection of internal organs and support of body. Making of special things in the body, e.g. digestive juices given to certain cells called gland cells. Working together or coördination of different organs provided for by nervous system. This is composed of cells which are highly irritable or sensitive. Collections of these nerve cells give us the power of feeling or sensation and of thinking.
Dietetics. Diet influenced by age, weight, occupation, temperature or climate, cheapness of food, digestibility.
Nutrients. List of nutrients found in seeds and fruits, also other common foods. Need of nutrients for human body. Nitrogenous foods, examples. A mixed diet best.
Digestion and Indigestion. What is digestion? Where does it take place? Causes of indigestion. Eating too rapidly and not chewing food. Eating foods hard to digest. Overeating. Eating between meals. Hard exercise immediately before or after eating.
Constipation. A condition in which the bowels do not move at least once every day. Dangers of constipation. Poisonous materials may be absorbed, causing lack of inclination to work, headache. Importance of regular habits of emptying the bowels. Each one must try to get at the cause of constipation in his own case. Causes of constipation. Lack of exercise, improper food, not drinking enough water, lack of laxative food, as fruits; lack of sleep, lack of regular habits. Remedies. Avoid use of drugs. Half hour before breakfast a glass of hot water, exercise of abdominal muscles, laxative foods, form habit of moving bowels after breakfast.
Hygiene of Circulation and Absorption. How digested foods get to the cells. Absorption. Definition. The passing of the digested food into the blood. How accomplished. Blood vessels. In walls of stomach and food tube. Membrane of cells separating food from blood. Food passes by osmosis through the membrane and by osmosis through the thin walls of the blood vessels.
Circulation of Foods. Blood contains foods, oxygen, and waste materials. Heart pumps the blood, blood vessels subdivide until very small and thin, so food, etc., passes from them to cells. Hygiene of the heart.