Transcript Nutrition and Digestion Next Week

Today:
Nutrition and
Digestion
Next Week:
Circulation,
Respiration,
and 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
Federal Food Subsidies vs Food Pyramid
http://www.pcrm.org/magazine/gm07autumn/health_pork.html
Protein needed per day =
0.8g/kg of body weight
So a 150 lb person needs 54 g or 2 oz of
protein/day
CB
5.17
CB 41.10
8 Essential Amino Acids
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 Society
for 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 Odors
S Libert, J Zwiener, X Chu, W VanVoorhies, G
Roman, S Pletcher
Science Vol. 315:1133 - 1137
23 February 2007
Smelling food reduces life span in CR flies
Calorie Restricted Flies
Normal Diet 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
Flies lacking the Or83b
gene are resistant to
starvation
Fig 4B
Smelling food reduces life span in CR flies
Calorie Restricted Flies
Normal Diet Flies
Fig 1
Calorie Restriction related websites:
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
Cause-Specific Excess Deaths Associated
with Underweight, Overweight, and Obesity
Flegal KM et al
JAMA, 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 a
TIFF (Uncompressed) decompressor
are needed to see this picture.
CVD= cardiovascular disease
JAMA, November 7, 2007—Vol 298, No. 17 pg 2028-37
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
JAMA, November 7, 2007 Vol 298: 2028-37
The Digestive System
CB 41.15
light
Photosynthesis
CO2 + H2O
C6H1206 + O2
sugar
Cellular Respiration
C6H1206 + O2
sugar
CO2 + H2O
energy
ADP
ATP
Cells store
energy in
ATP
Energy used
Energy released
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.
Physical digestion:
liquefying of food
Chemical digestion:
breaking large molecules
into small molecules
CB 41.21