Today:Today:Nutrition and Nutrition and DigestionDigestionNext Week:Next Week:Circulation, Circulation, Respiration,Respiration,and Reproductionand Reproduction

During digestion complex molecules are broken down and then used to build needed molecules and to produce energy

Food Pyramid based on 2,000 calories/day

http://www.pcrm.org/magazine/gm07autumn/health_pork.html

Federal Food Subsidies vs Food Pyramid

Protein needed per day = 0.8g/kg of body weight

So a 150 lb person needs 54 g or 2 oz of protein/day

20 ami n

o a cids

CB5.17

8 Essential Amino AcidsCB 41.10

Many cultures combine these foods in their traditional diets: beans and rice, beans and corn, peanut butter on bread, soy and rice, lentils and bread or rice

CB 41.10

The Calorie Restriction Societyfor people trying to live longer by eating fewer calories

http://youtube.com/watch?v=YTQR7o9ap9Y

Regulation of Drosophila Life Span by Olfaction and Food-Derived OdorsS Libert, J Zwiener, X Chu, W VanVoorhies, G Roman, S PletcherScience Vol. 315:1133 - 113723 February 2007

Calorie Restricted Flies Normal Diet Flies

Smelling food reduces life span in CR flies

Fig 1

Flies with a poor sense of smell live longer Or83b is a gene involved in the fly’s sense of smell

Fig 2A

Fig 4B

Flies lacking the Or83b gene are resistant to

starvation

Calorie Restricted Flies Normal Diet Flies

Smelling food reduces life span in CR flies

Fig 1

http://www.calorierestriction.org/

http://www.cbsnews.com/stories/2005/12/30/eveningnews/main1172297.shtml

http://stke.sciencemag.org/cgi/content/full/sci;315/5815/1133

http://stke.sciencemag.org/cgi/content/full/sci;315/5812/584

Calorie Restriction related websites:

JAMA, November 7, 2007—Vol 298, No. 17 pg 2028-37

Cause-Specific Excess Deaths Associatedwith Underweight, Overweight, and ObesityFlegal KM et alJAMA, November 7, 2007—Vol 298, No. 17 pg 2028-37

Overweight (BMI 25-30) people live longer than normal (BMI 18.5-25), underweight (BMI<18.5), or obese (BMI>30) people

JAMA, November 7, 2007—Vol 298, No. 17 pg 2028-37

Overweight people live longer than normal, underweight, or obese people for all causes of death

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

CVD= cardiovascular disease

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are needed to see this picture.

JAMA, November 7, 2007 Vol 298: 2028-37

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

CB 41.15

The Digestive System

CO2 + H2O C6H1206 + O2

CO2 + H2OC6H1206 + O2

light

sugar

sugar

Photosynthesis

Cellular Respiration

ATP

energy

ADP

Energy used Energy released

Cells store energy in ATP

Using ATP

Complex molecules are broken down and then used to build needed molecules and to produce energy

Animals take in complex molecules from the environment for energy production

Animal digestion occurs outside of our cells.

animal and fungal digestion occurs outside of our cells.

CB 41.21

Physical digestion:liquefying of food

Chemical digestion:breaking large moleculesinto small molecules