Lecture 2 02/16/2014
Nutrients that are consumed are needed to survive and used by the body.
Carbohydrates: organic molecules that are soluble in water, hydrophilic; 3 classes:
monosaccharideglucose, galactose, fructose. (only type that can be absorbed in the bloodstream.
Dimersdisaccharide like glucose+fructose=sucrose
Polysaccharidesstarch and cellulose in plants and glycogen in animals.
Every single cell can use glucose to breakdown and gain energy; uses O2 to be broken down which
releases heat▯heat used to maintain body temperature.
Glucose▯▯▯(glycolysis, in the cystol and anaerobic)▯breakdown products are pyruvate and lactate.
Pyruvate gets broken down▯ATP, CO2, Heat, H2O (in the mitochondria with O2▯aerobic). Lactate▯causes
acidity; the liver can converts to glucose and releases into the blood.
CO2 is toxic in the body because it can react with H2O and increase the H+ concentration and increasing
the pH balance. There is an optimal pH for enzymes to function properly (very small range) and therefore
the pH is tightly controlled.
The urinary system and respiratory system: most important to regulate PH in the body.
Circulatory systemregulates body temperature (dilation/constriction) dilation brings heat to the surface to
Liver and skeletal muscles store glycogen for energy for later use. Liver stores glycogen for the body;
skeletal muscle stores for itself (built in storage) –glycogenolysis by liver and skeletal muscle.
Nervous system activates glycogenolysis and the endocrine system by hormones. Hormones: chemical