An Introduction to Internal Systems

1. Why do we need to eat? An Introduction to Internal Systems

2. The Human Body

3. Can you figure out which organ system of the human body this is?

4. Can you figure out which organ system of the human body this is?

5. In this unit, we will specifically be looking at three systems: • Digestive system • Respiratory system • Circulatory system

6. We have a few essentials that we need in order for us to survive. • Imagine you are on the show survivor: • what would you need in order for you to be able to make it out alive • and perhaps win some BIG

7. Things needed to survive:

8. Nutrition (food and water are one of the major things we need to live ... and this is not just on survivor) • Our bodies are designed to help us get this nutrition ... we call this our digestive system

9. Nutrition • Living things’ ability to eat food • Use the components of those foods to fuel growth and development • Need good nutrition to be healthy • If we eat poorly, we are more likely to be sick and unhealthy Your body is just like a factory  Food is the fuel that keeps it running

10. Nutrient #1: Water (H2O) • Not a source of energy. • Needed by all cells of the body (known as the “universal solvent” since many substances can dissolve in water). • Makes up a large component of blood. • Need to drink about 8 glasses of water per day.

11. Nutrient #2: Carbohydrates • provides the body with energy. • carbohydrates are broken down during digestion to make glucose (the most simple carbohydrate). • glucose is then sent to the mitochondria where chemical reactions take place to release energy (in the form of ATP = adenosine triphosphate). • makes up 55-60% of the diet we eat.

12. Monosaccharides (“simple sugars”) glucose

13. Disaccharides = “two simple sugars joined together”

14. Polysaccharides = “complex carbohydrates” = long chains of sugar units E.g.cellulose (no branching) E.g. Starch or amylose (some branching) E.g. Glycogen (highly branched)

15. Polysaccharides • cellulose – very long chain of glucose units, provide structure for plant cell walls • starch – polysaccharides of mostly glucose units, store energy in plant cells • glycogen – polysaccharides of glucose units, store energy in animal cells

16. Nutrient #3: Lipids (Fats) • Main function is to store energy for later use. • Insulates the body, protect organs, and fats make up some hormones (e.g. testosterone) • Broken down into triglycerides when digested • Make up 30% of our diet

17. common types of lipids are fats and oils • there are two (2) forms of triglyceride: saturated -single bonds = straight chain solid at room temperature and • unsaturated -double bonds = kinks liquid at room temperature healthier

18. Nutrient #4: Proteins • Proteins are the building blocks for the body (they help us grow and repair). • Also function as enzymes to speed up chemical reactions that happen in the body. • Broken down into amino acids when digested by the body. • Makes up 10-15% of our diet.

19. Proteins • Examples include hormones, organelles, hemoglobin, antibodies • There are 20 amino acids from which proteins are built • Human body can make twelve (12) of these amino acids, so we need to obtain the other eight (8) from food sources • Animal sources: meat, eggs, fish, cheese • Plant sources: beans, lentils, seeds, nuts

20. Protein Structure

21. Factory analogy and types of food we eat...

22. Mechanical vs. Chemical Digestion Physical Digestion = chewing, mashing, chopping, breaking food into smaller pieces and the physical movement of food (peristalsis). Chemical Digestion = chemicals called digestive enzymes and water break down small pieces of food into even smaller molecules that can be absorbed at the cellular level.

23. Video: “Breaking Down Digestion” (Assignment Discovery) http://videos.howstuffworks.com/discovery/28649-assignment-discovery-breaking-down-digestion-video.htm