The digestive system breaks down food into smaller molecules using specialized enzymes. Nutrients are then absorbed into the bloodstream and used by cells through metabolic reactions to produce energy, build substances, and drive cellular activities. Nutritional needs vary between individuals based on their age, gender, height, weight, and activity level.

1. THE DIGESTIVE SYSTEM
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2. STATION 23: Nutrition
The breakdown
of food into
smaller
molecules relies
on specialized
enzymes for
each type of
macromolecule.

3. STATION 23: Nutrition
Once inside body cells, the nutrients become involved in an incredible
variety of chemical reactions known as metabolism.
• All of the nutrients absorbed into the blood stream are either
broken down or build up into usable substances.
• Cells use energy to extract more energy from food, and to drive
their activities.
• Carbohydrates are the body’s preferred source to produce cellular
energy through the process of cellular respiration.

4. STATION 23: Nutrition
Nutritional requirements, including energy (caloric needs), vary with the
individual’s:
1. Age
2. Gender
3. Height
4. Weight
5. Metabolic/Physical Activity

5. STATION 23: Nutrition