A&P 2 Exam 1 - Metabolism

Six Categories

Carbohydrates, lipids (fats), proteins, water, vitamins, and minerals.

Carbohydrates

Source: primarily plants and animals.

Lipids (fats)

Source: saturated = animals, unsaturated = plants.

Proteins

Source: Plants and or animals. Usage: Structural and regulatory molecules (enzymes/hormones).

Water

A solvent, reactant, lubricant, temperature regulator, etc.

Vitamins

Organic molecules that the body cannot synthesize… but needs for normal metabolism; often they are part of an enzyme, therefore, must consume them or their precursors.

Minerals

Necessary inorganic elements or small molecules which are often used as essential portions of larger molecules, ions, or to mineralize such things as bone.

Catabolism (digestion)

The breakdown or decomposition or large molecules into smaller ones; this process involves the breaking of chemical bonds and the release of the energy stored in the bonds.

Anabolism

The opposite process; involving chemical reactions which build up or synthesize large molecules from smaller building blocks; consume or require energy to drive them (input of energy); activation energy is energy input required to start a chemical reaction.

Enzyme

A biological catalyst; proteins (sometimes nucleic acids) which speed up reaction rates (lower activation energy); ultimately, bodily control of metabolism is through the control of the type and amount of enzymes which are synthesized; generally speed up reaction rates by physically bringing the reactants together, increasing the likelihood of their reacting.

Adenosine Triphosphate (ATP)

Provides energy for all the various metabolic reactions involved in life; the energy not trapped as ATP escapes as heat.

2 ATP molecules

ATP produced from glycolysis per glucose molecule.

38 ATP (per glucose)

ATP produced from glycolysis, kreb’s cycle, and electron transport per glucose molecule.

Breathing in O2

To power chemical reactions in our bodies that create energy.

Breathing out CO2

Comes from cellular respiration; CO2 is a byproduct.

Nutrient Absorption

Absorptive state is the time period during and after meals; during this time you are glucose rich and the dominate hormone is Insulin; Post absorptive state is the period when the GI tract is empty, glucose poor, dominate hormone is glucagon.

Metabolic Rate

Exercise/activity level has the greatest effect; hormones (thyroid hormone, epinephrine/noepinephrine, growth hormone, testosterone); age (rate decreases with age); sex (lower in females (except during pregnancy and lactation)); body surface area compared to volume (thinner people have a higher rate); food (during digestion it increases); body temperature (goes up with temperature).