31 terms

Ch. 7 Metabolism

Sum total of all chemical reactions that go on in living cells
Reactions in which small molecules are put together to build larger ones. anabolic reactions require energy. Ex: glucose+glucose=maltose
Reactions in which large molecules are broken down to smaller one. Catabolic reactions release energy. Ex: lactose=glucose+galactose
Energy released in catabolic reactions is captured by a "high energy storage compound"
Is formed through the electron transport chain
regenerates to ATP following a catabolic reaction when energy is released
Catabolic reactions
release energy and form ATP from ADP
Anabolic reactions
use energy and ADP is formed from ATP
formation of ATP
occurs in the mitochondria in the electron transport chain
most versatile and metabolically active of all the bodys cells
first step in glucose metabolism
Energy released is formed into ATP in Electron Transport Chain. Two paths from pyruvate are available ... path taken depends on oxygen availability
Usual Pathway from Pyruvate
The Aerobic Pathway from Pyruvate-to-Acetyl CoA *
* Cori Cycle
(anaerobic pathway) occurs when Oxygen is not available
Alternative Pathway from Pyruvate
Cori Cycle (Pyruvate-->Lactic Acid -->Glucose)
Anaerobic reaction
occurs in absence of oxygen, yield 2 ATP per glucose mol
aerobic reactions
yield 8 ATP per glucose mol
central pathway of energy metabolism:
glucose to energy pathway
removal of an amino group
the transfer of amino groups from one amino acid to another amino acid. Vitamin B6 is required for transamination reactions
Deaminated Nitrogen Is
1. converted to ammonia
2. combined with CO2 to produce urea
-synthesis occurs in the liver
-excreted by kidneys
Urea Excretion
-H2O needed to excrete urea
-Urea is the body's main method of ridding itself of Nitrogen
-higher protein intake = higher Nitrogen = higher urea production
- higher H2O necessary with higher protein intake
-High protein diets place extra strain on kidneys
The krebs cycle
Any substance that can be converted to acetyl CoA directly, or indirectly through pyruvate, may enter the cycle
Fat formation=
excess consumption of protein, fat, or carbs
Glycogen (limited) and Fat (TGY)
the form that our body stores excess nutrients
The formation of glycogen, a glucose storing compound, from fatty acids and proteins rather than carbohydrates. Protein meets glucose via this
body finds a way to use fat to fuel the brain...BAD. acetyl CoA gragments combine to form ketone bodies for energy...BAD
effects of ketosis
-suppression of appetite
-slowing of metabolism
-symptoms of starvation
starvation occurs in
-starving child
-hungry homeless person
-person who fasts
-adolescent with anorexia nervosa
-malnourished hospital patient
symptoms of starvation
-slowing energy output
-reduction in fat loss
-wasting, lower metabolism, body temp,disease resistance