Term
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Definition
| Body temperature regulation at rest |
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Term
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Definition
| Body temperature regulation during exercise |
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Term
| biological control system |
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Definition
| Series of interconnected components that maintain a physical or chemical parameter at a near constant value |
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Term
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Definition
Detects changes in variable
(baroreceptors) |
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Term
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Definition
Assesses input and initiates response
(CV control center) |
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Term
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Definition
Changes internal environment back to normal
(blood vessels) |
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Term
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Definition
Response reverses the initial disturbance in homeostasis.
Example:
Increase in extracellular CO2 triggers a receptor
Sends information to respiratory control center
Respiratory muscles are activated to increase breathing
CO2 concentration returns to normal
Most control systems work via negative feedback |
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Term
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Definition
Response increases the original stimulus
Example:
Initiation of childbirth stimulates receptors in cervix
Sends message to brain
Release of oxytocin from pituitary gland
Oxytocin promotes increased uterine contractions |
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Term
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Definition
Degree to which a control system maintains homeostasis
System with large gain is more capable of maintaining homeostasis than system with low gain
Pulmonary and cardiovascular systems have large gains |
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Term
| Examples of Homeostatic Control |
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Definition
Regulation of body temperature
Regulation of blood glucose
Cellular stress proteins |
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Term
| Regulation of body temperature |
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Definition
Thermal receptors send message to brain
Response by skin blood vessels and sweat glands regulates temperature |
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Term
| Regulation of blood glucose |
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Definition
Requires the hormone insulin
Diabetes
Failure of blood glucose control system |
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Term
| Regulation of cellular homeostasis |
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Definition
Stress proteins (heat shock proteins)
Repair damaged proteins to restore homeostasis in response to changes in temperature, pH, and free radicals |
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Term
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Definition
Exercise represents a challenge to the body’s control systems to maintain homeostasis.
In general, the body’s control systems are capable of maintaining a steady state during most types of exercise in a cool environment.
However, intense exercise or prolonged work in a hostile environment (i.e., high temperature/ humidity) may exceed the ability of a control system to maintain steady state, and severe disturbances of homeostasis may occur. |
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Term
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Definition
Exercise disrupts homeostasis by changes in pH, O2, CO2, and temperature
Control systems are capable of maintaining steady state during submaximal exercise in a cool environment
Intense exercise or prolonged exercise in a hot/humid environment may exceed the ability to maintain steady state
May result in fatigue and cessation of exercise |
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Term
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Definition
A biological control system is composed of a sensor, a control center, and an effector.
Most control systems act by way of negative feedback.
The degree to which a control system maintains homeostasis is termed the gain of the system. A control system with a large gain is more capable of maintaining homeostasis than a system with a low gain. |
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Term
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Definition
Semipermeable membrane that separates the cell from the extracellular environment
Enclose Components and regulate passage – in & out |
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Term
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Definition
Contains genes that regulate protein synthesis
Molecular biology |
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Term
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Definition
Metabolism - the total of all cellular reactions that occur in the body; includes both the synthesis of molecules and the breakdown of molecules.
Cell structure -- three major parts: (1) cell membrane, (2) nucleus, and (3) cytoplasm (called sarcoplasm in muscle).
The cell membrane -- a protective barrier between the interior of the cell and the extracellular fluid.
Genes (located within the nucleus) regulate protein synthesis within the cell.
The cytoplasm -- fluid portion of the cell and contains numerous organelles |
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Term
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Definition
Require energy to be added
Endothermic
End Products > Reactants |
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Definition
Release energy
Exothermic |
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Term
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Definition
| Liberation of energy in an exergonic reaction drives an endergonic reaction |
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Term
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Definition
| Converting foodstuffs (fats, proteins, carbohydrates) into a biologically usable form of energy |
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Term
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Definition
Proteins - - play a major role in regulation of metabolic pathways
Catalysts that regulate the speed of reactions
Lower the energy of activation
Factors that regulate enzyme activity
Temperature
pH
Interact with specific substrates
Lock and key model |
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Term
| factors that alter enzyme activity |
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Definition
Temperature
Small rise in body temperature increases enzyme activity
Exercise results in increased body temperature
pH
Changes in pH reduces enzyme activity
Lactic acid produced during exercise |
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Term
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Definition
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Term
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Definition
Fats and carbohydrates are the primary nutrients
Small amount of total energy – from Proteins |
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Term
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Definition
Stored carbohydrates
Rapidly available form of energy, 1 gm of CHO = 4 kcal
3 forms
Monosaccharides
Glucose – Blood sugar; Fructose – fruits and honey
Disaccharides
Sucrose – table sugar; Maltose – 2 glucose molecules
Polysaccharides
3 or more monosaccharides
Plant tissue - Cellulose and Startch
Animal tissue - Glycogen |
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Term
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Definition
Fatty acids
Primary type of fat used by the muscle
Triglycerides
Storage form of fat in muscle and adipose tissue
Breaks down into glycerol and fatty acids
Phospholipids
Not used as an energy source
Steroids
Derived from cholesterol
Needed to synthesize sex hormones |
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Term
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Definition
Composed of amino acids
Some can be converted to glucose in the liver
Gluconeogenesis
Others can be converted to metabolic intermediates
Contribute as a fuel in muscle
Overall, protein is not a primary energy source during exercise |
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Term
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Definition
The body uses carbohydrate, fat, and protein nutrients consumed daily to provide the necessary energy to maintain cellular activities both at rest and during exercise. During exercise, the primary nutrients used for energy are fats and carbohydrates, with protein contributing a relatively small amount of the total energy used.
Glucose is stored in animal cells as a polysaccharide called glycogen.
Fatty acids are the primary form of fat used as an energy source in cells. Fatty acids are stored as triglycerides in muscle and fat cells. |
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Term
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Definition
Adenosine triphosphate (ATP)
Consists of adenine, ribose, and three linked phosphates
Synthesis :ADP + Pi ATP
breakdown:ATP ADP + Pi + Energy |
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Term
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Definition
ATP-PC system
Immediate source of ATP
Glycolysis
Glucose 2 pyruvic acid or 2 lactic acid
Energy investment phase
Requires 2 ATP
Energy generation phase
Produces 4 ATP, 2 NADH, and 2 pyruvate or 2 lactate |
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Term
| Aerobic ATP production (oxidative phosphorylation): |
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Definition
Krebs cycle (citric acid cycle)
Pyruvic acid (3 C) is converted to acetyl-CoA (2 C)
CO2 is given off
Acetyl-CoA combines with oxaloacetate (4 C) to form citrate (6 C)
Citrate is metabolized to oxaloacetate
Two CO2 molecules given off
Produces three molecules of NADH and one FADH
Also forms one molecule of GTP
Produces one ATP |
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Term
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Definition
The immediate source of energy for muscular contraction is the high-energy phosphate ATP. ATP is degraded via the enzyme ATPase as follows:
Formation of ATP without the use of O2 is termed anaerobic metabolism. In contrast, the production of ATP using O2 as the final electron acceptor is referred to as aerobic metabolism. |
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Term
| Anaerobic ATP production: |
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Definition
(a) ATP-PC system
(b) Glycolysis |
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Term
| Aerobic ATP production (oxidative phosphorylation): |
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Definition
(a) Krebs cycle (Oxidation of CHO, Fats and Proteins)
(b) Electron transport chain |
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Term
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Definition
Glycolysis alone:
Glucose (2 ATP), glycogen (3 ATP)
Aerobic ATP production:
Glucose (32 ATP), glycogen (33 ATP) |
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Term
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Definition
Exercising skeletal muscles produce lactic acid. However, once produced in the body, lactic acid is rapidly converted to its conjugate base, lactate.
Muscle cells can produce ATP by any one or a combination of three metabolic pathways: (1) ATP-PC system, (2) glycolysis, (3) oxidative ATP production.
The ATP-PC system and glycolysis are two anaerobic metabolic pathways that are capable of producing ATP without O2. |
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Term
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Definition
The aerobic metabolism of one molecule of glucose results in the production of 32 ATP molecules, whereas the aerobic yield for glycogen breakdown is 33 ATP.
The overall efficiency of aerobic of aerobic respiration is approximately 34%, with the remaining 66% of energy being released as heat. |
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Term
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Definition
Energy to perform exercise comes from an interaction of anaerobic and aerobic pathways.
In general, the shorter the activity (high intensity), the greater the contribution of anaerobic energy production. In contrast, long-term activities (low to moderate intensity) utilize ATP produced from aerobic sources |
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Term
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Definition
| via ADP/ATP stimulation or inhibition of creatine kinase activity |
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Term
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Definition
| via ADP/ATP stimulation or inhibition of PFK activity |
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Term
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Definition
| by regulation of isocitrate dehydrogenase activity (i.e., ADP stimulates, whereas ATP inhibits) |
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Term
| Electron transport chain activity |
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Definition
| via the amount of ATP and ADP present |
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Term
| Interaction between aerobic and anaerobic ATP production |
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Definition
comes from both aerobic and anaerobic sources
400-meter run (i.e., 75% anaerobic/25% aerobic) |
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