(a) Summary of major pathways of organic metabolism. Cells continually synthesize and break down car

(a) Summary of major pathways of organic metabolism. Cells continually synthesize and break down carbohydrates, fats, and proteins. Most urea forms in the liver, an organ that is at the cross-roads of organic metabolism (b).


FOOD INTAKE dietary carbohydrates. lipids Cytoplasmic Pool of Carbohydrates, Fats (interconvertible forms) storage building specialized instant forms blocks for derivatives energy (e.g., cell (ecgn steroids, sources glycogen) structures acetylcholine) for cells dietary proteins, amino acids —> ‘— Cytoplasmic Pool F of Amino Acids ammonia l l I urea nitrogen- building containing blocks for derivatives structural (5.9., hormones, proteins, excreted nucleotides) enzymes in urine Liver Functions Forms bile (assists fat digestion), rids body of excess cholesterol and blood's respiratory pigments Controls amino aCld levels in the blood; converts potentially toxic ammonia to urea Controls glucose level in blood; malor reservoir for glycogen Removes hormones that sewed their functions from blood Removes ingested toxins, such as alcohol, from blood Breaks down worn-out and dead red blood cells, and stores iron Stores some Vitamins