40 terms

Nutrition, metabolism

glucose serves as the initial reactant
krebs cycle
involves the formation of a 6-carbon molecule and its successive degradation to a 4-carbon pickup molecule
occurs in the cytoplasm
glycolysis, krebs, etc
produces atp
electron transport chain
involves removal and/or transfer of hydrogen (or electrons) from the substrate molecule
beta oxidation
takes place in mitochondria, occurs when fats are used instead of sugars to produce ATP.
the carbohydrates we ingest are mostly from ____
essential nutrient
____ _____ - Required by cells and must be obtained from dietary sources
Lipids containing a glycerol molecule attached to three fatty acid chains; chemical form in which most fats exist in food and in the body.
nitrogen balance
the balance between the amount of nitrogen taken in (to the soil or the body) and the amount given off (lost or excreted)
Essential nutrients that do not yield energy, but that are required for growth and proper functioning of the body.
inorganic substances that the body cannot manufacture but that act as catalysts, regulating many vital body processes
in cellular respiration, series of ananerobic chemical reactions in the cytoplasm that breaks down glucose into pyruvic acid; forms a net profit of two ATP molecules
atp molecules
usable energy source; adenosine triphosphate; 3 phosphate + 1 sugar; common carrier of energy in cells. Cell gains 34 atp molecules from aerobic metabolism of one glucose molecule
macromolecule that contains carbon, hydrogen, oxygen, and nitrogen; needed by the body for growth and repair and to make up enzymes. Dietary proteins mainly animal
the molecule that serves as the major source of readily available body fuel
a class of nutrients that does not mix with water. made mostly of fatty acids, which provide energy to the body.
acetyl CoA
The entry compound for the Krebs cycle in cellular respiration; formed from a fragment of pyruvate attached to a coenzyme.
dietary fat
helps transport fat-soluble vitamins (A, D, E, K), contributes to flavour and texture of foods, gives us a feeling of satiety
complete protein
protein source with all essential amino acids
A small, very toxic molecule (NH3) produced as a metabolic waste product of protein and nucleic acid metabolism. Found in urine when proteins undergo deamination
the removal of an amino group from an organism, particularly from an amino acid
the process of transfering an amino group from one compound to another
ketone bodies
the product of the incomplete breakdown of fat when glucose is not available in the cells. highly acidic, made in liver
The process that synthesizes a complex molecule from simpler compounds, thus requiring energy.
breakdown of more complex substances into simpler ones with release of energy
When the stomach and small intestine are empty and the body is drawing on its stored energy reserves, it is in the __________ state.
a hormone secreted by the pancreas, The antagonist of insulin. Its release is stimulated by low blood glucose levels. It stimulates the liver, to break down its glycogen stores to glucose and subsequently to release glucose to the blood.
An adenine-containing nucleoside triphosphate that releases free energy when its phosphate bonds are hydrolyzed. This energy is used to drive endergonic reactions in cells.
oxidative phosphorylation
Part of the electron transport chain. A process occurring in the mitochondria that results in the formation of ATP from the flow of electrons across the inner membrane to bind with oxygen.
breakdown of triglycerides to glycerol and fatty acids
generation of glucose from non-sugar carbon substrates like pyruvate, lactate, glycerol, and amino acids. The vast majority takes place in the liver and, to a smaller extent, in the cortex of kidney. This process occurs during periods of fasting, starvation, or intense exercise and is highly endergonic.
reactions that absorb energy
______ occurs when cellular atp and glucose levels are high. Creation of triglycerides (fat-- fatty acids and glycerol) - moves fatty acids out of bloodstream to store in adipose tissue
Krebs cycle produces ___ (how many) atp per glucose molecule?
ketone bodies
Fat burning causes an accumulation of acetyle CoA, which the liver converts to______
amino acids
_____ _____ cannot be stored; those not used immediately to build proteins are oxidized for energy or converted to carbohydrates or fats.
heat stroke
the body is unable to eliminate the excess heat. A medical emergency consisting of a fever of at least 105 F, hot dry skin, rapid heartbeat, rapid and shallow breathing, and elevated or lowered blood pressure caused by the breakdown of the body's cooling mechanism.
heat exhaustion
fatigue, headache, nausea, fainting caused by additional water loss
4 basic stages of glycolysis
1. atp input 2. cleavage (costs cell 2 atp) 3. atp nadh production (4 atp, 2 nadah per glucose) 4. pyruvic acid formation