Metabolism Flashcards
What is the training effect?
An increase in functional capacity of muscles and other bodily tissues as a result of increased stress(overload) places upon them
What is homeostasis?
The automatic tendency to maintain a relatively constant internal environment
What are carbohydrates?
Sugars and starches used by the body as fuel
What are fats?
Compounds that store energy
What are proteins?
Large, complex molecules comprised of amino acids
What is a good example of homeostasis in the body?
Method by which the body maintains a constant temperature of 98.6 degrees Fahrenheit
What happens when your body temperature rises due to physical exertion or external heat?
Brain sends a signal to increase the rate of sweating
What happens when body temperature begins to drop due to a cold external environment?
Shivering begins to generate heat for the body
What are some other functions under homeostatic control?
- Hormone production
- pH balance in the blood
- Water content of cells and blood
- Blood glucose levels
- Metabolic rate
What is metabolism?
Total of all chemical and physical processes by which the body builds and maintains itself(anabolism) and by which it breaks down its substances for the production of energy(catabolism)
What is anabolism?
The building up in the body of complex chemical compounds from simpler compounds
What is catabolism?
The breaking down in the body of complex chemical compounds into simpler ones
What is glucose?
Principal circulating sugar in the blood and the major energy source of the body
What are ketone bodies?
Bodies produced as intermediate products of fat metabolism
What is lactic acid?
A by-product of glucose and glycogen metabolism in anaerobic muscle energetics
What are amino acids?
Building blocks of protein
How many amino acids are there?
24
What are fatty acids?
Any of a large group of monobasic acids, especially those found in animal and vegetable fats and oils
What is the metabolic set point?
The base rate of metabolism that the body seeks to maintain; resulting in nasal metabolic rate
What is basal metabolic rate(BMR)?
The minimum energy required to maintain the body’s life function at rest; usually expressed in calories per hour per square meter of the body’s surface
What is the thermic effect?
The heat liberated from a particular food; it is a measure of its energy content and its tendency to be burned as heat. Also referred to as “thermogenesis”
What is a calorie?
A unit of heat; amount of energy required to raise the temperature of 1 gram of water 1 degree Celsius at 1 atmosphere
What is a kilocalorie?
1,000 calories and the preferred unit in metabolism studies
What is the respiratory quotient(RQ)?
A method of determining the “fuel mix” being used, giving us a way to measure the relative amounts of fats, carbohydrates and proteins being burned for energy
What is the formula for calculating RQ?
RQ = volume of CO2 expired / volume of O2 utilized
What is the respiratory quotient(RQ) of carbohydrate?
1.0
What is the respiratory quotient(RQ) for fat?
0.7
What is the RQ for protein?
About 0.8
In a normal diet, what is the percent of energy derived from carbohydrates, fats and proteins?
Carbohydrates = 40-45%
Fatty acids = 40-45%
Proteins = 10-15%
What is oxidation?
The chemical act of combining with oxygen or of removing hydrogen
What is maximal oxygen uptake?
Highest rate of oxygen consumption which a person is capable of
What are branched-chain amino acids(BCAA’s)?
Amino acids L-leucine, L-Isoleucine an L-valine which have a particular molecular structure that gives them their name and comprises 35% of muscle tissue. They help increase work capacity by stimulating production of insulin
What is Adenosine Triphosphate(ATP)?
An organic compound found in muscle which, upon being broken down enzymatically, yields energy for muscle contraction
What is Creatine Phosphate(CP)?
A high-energy phosphate molecule that is stored in cells and can be used to immediately resynthesize ATP
Describe the ATP/CP pathway?
ATP and CP provide anaerobic sources of phosphate-bond energy. The energy liberated from hydrolysis(splitting) of CP re-bonds ADP and Pi to form ATP
What is Adenosine Diphosphate(ADP)?
An organic compound in metabolism that functions in the transfer of energy during the catabolism of glucose, formed by the removal of a phosphate molecule from adenosine trisphosphate and composed of adenine, ribose, and two phosphate groups
How much ATP is stored in muscles?
5 mmol/kg of muscle
How much CP is stored in muscles?
16 mmols/kg of muscle
What are type II muscle fibers?
Fast twitch - contracts quickly and is used mostly in intensive, short duration exercises
What are type I muscle fibers?
Slow twitch - characterized by slow speed of contraction and a high capacity for aerobic glycolysis
What is the glycolytic pathway?
Metabolic process in which glucose is broken down to produce energy anaerobically
What is gluconeogenesis?
Chemical process that converts lactate and pyruvate back into glucose. When glycogen stores are low, glucose for emergency is synthesized from protein and the glycerol portion of fat molecules.
What is the anaerobic threshold?
The point where increasing energy demands of exercise can not be met by the use of oxygen, and an oxygen debt begins to be incurred
What is the oxidative pathway?
Metabolic process by which oxygen combines with lactic acid, resynthesizing glycogen to produce energy aerobically
What is the Krebs cycle?
Citric acid cycle; a set of 8 reactions, arranged in a cycle, in which free energy is recovered in the form of ATP
What is the electron transport chain?
The passing of electrons over a membrane, aiding in a reaction to recover free energy for the synthesis of ATP
What is pyruvate?
A byproduct of glycolysis
What is beta oxidation?
A series of reactions in which fatty acids are broken down
What is resting metabolic rate(RMR)?
The amount of energy(calories) required to efficiently perform vital bodily functions such as respiration, organ functions and heart rate while the body is awake, but at rest
