Exam 1 Flashcards
(26 cards)
Homeostasis
Maintenance of a constant and “normal” internal environment – normal resting condition
Steady State
Physiological variable is unchanging, but not necessarily “normal”
Balance between demands placed on body and the body’s response to those demands
EXAMPLE: Body temperature; Arterial blood pressure
Biological Control System
Series of interconnected components that maintain a physical or chemical parameter at a near constant value
Components of Biological Control System
- Sensor or Receptor: Detects change
- Control Center: Assesses input, initiates and integrates response
- Effector: Changes internal environment back to normal (Cell, organ that produces desired effects
Negative Feedback
Something has gone out of control and homeostasis must be restored
Response of control system is opposite to stimulus
Positive Feedback
Increases original stimulus (escalates)
Response in same direction as stimulus
What disrupts homeostasis?
Exercise (improves)
Cell Signaling
Coordinates cell activity
Bioenergetics
Converting food into energy
Coupled Reactions
Reactions that are linked together. One produces the energy needed for the other
Oxidation Reduction Reactions
Oxidation: Removal of electron
Reduction: Addition of electron to atom
Substrates and Products
Substrate: Molecule acted on by enzyme reaction, results in manufacture of proteins
Product: Molecules manufactured from substrates that are involved in catalyzed reactions
Glycolysis
Breakdown of glucose to form 2 pyruvate or lactate
Energy generation: 2 or 3 ATP
2 NADH
Oxidized Phosphorylation
Generation of Acetyl CoA
Krebs Cycle and ETC
Acetyl CoA
Formed from breakdown of carbs, proteins, and fats
For every molecule of glucose = 2 pyruvate formed
Krebs Cycle
3 NADH 1 FADH2 1 GTP Waste product = CO2 10 ATP x 2 cycles = 20 ATP (ATP not formed until ETC
Electron Transport Chain
Oxidized phosphorylation mitochondria
Waste product = h2o
Oxidized Phosphorylation ATP produced?
32 ATP (33 is glycogen is used)
ATP-PC
Twice as fast as glycolysis
10 Seconds or less
Glycolysis
Uses glucose/glycogen
# of ATP 2 or 3 & 2 pyruvate or lactate
30 Seconds to 4 Minutes
Oxidized Phosphorylation
In Mitochondria
32 ATP produced
Respiratory Exchange Ratio (RER or R)
Ratio of volume of CO2 out to volume of O2 consumed
.7 RER for fat
1.00 RER for carbs
.85 means 50% of each
Low intensity burns more fat, but takes longer
VO2 Max
Most valid measure of cardiovascular fitness, physiological ceiling of O2 to muscle
Lactate Threshold
Point at which blood lactic acid uses systematically during incremental exercise
