1 Flashcards
1
Q
Steady State
A
Physiological variable is unchanging ,but not necessarily normal resting value
2
Q
Steady state example
A
Heart rate during submaximal exercise
3
Q
The maintained of a constant or unceasing normal internal environment during u stressed conditions
A
Homeostasis
4
Q
-Protein breakdown and synthesis
- Energy Production
-Maintenance of stored nutrients
A
Intracellular Control System
5
Q
Pulmonary and Circulatory Systems
Replenish oxygen and remove carbon dioxide
A
Organ systems
6
Q
Biological Control System
A
Series of interconnected components that maintain a physical or chemical parameter at a near constant value
7
Q
Detects changes in variable ( or stimulus )
A
Sensor or receptors
8
Q
Assesses input and initiates response
A
Control Center
9
Q
Changed internal environment back to normal
A
Effector
10
Q
Components to biological control systems
A
Sensor or receptor
Control center
Effector
11
Q
Response reverses the initial disturbance in homeostasis
Most control systems use this
A
Negative Feedback
12
Q
How does exercise disrupt homeostasis
A
By change in ph , po2, pco2 and temperature in cells
13
Q
Intense exercise or prolonged exercise in a hot/humid environment can what
A
Exceed the ability to maintain stead state
Ex. fatigue and cessation or exercise
14
Q
Biological control systems are called of maintaining steady state true or false
A
True
15
Q
What are two large gain control systems ( able to maintain homeostasis)
A
Pulmonary and Cardiovascular
16
Q
Increase the original stimulus
A
Positive feedback
17
Q
In child birth increase pressure on cervix = what
A
Increased oxytocin
18
Q
Change in structure and function of cell or organ system results in approved homeostasis
A
Adaptation
19
Q
Adaptation to environmental stresses ( heat stress) , results in improved function of homeostasis system
A
Acclimation
20
Q
-Communication between cells using chemical. messengers
-coordinates cellular
- important for homeostasis
A
Cell signaling
21
Q
Sum of all chemical reactions that occur in the body two general categories of Chemical reactions
A
Metabolism
22
Q
Synthesis of molecules
A
Anabolic reactions
23
Q
Breakdown of molecules
A
Catabolic reactions
24
Q
Process of converting foodstuffs ( fats , proteins, carbs) into usable energy for cell work
A
Bioenergetics
25
Semipermeable membrane that separates the cell from the extracellular environment
Cell membrane (sarcolemma of muscle fibers)
26
Contains genes that regulate protein synthesis
•Molecular biology
Nucleus
27
Fluid portion of cell
•Contains organelles
•Mitochondria
Cytoplasm (sarcoplasm)
28
Require energy to be added to the reactants.
Endergonic reactions (endothermic)
29
Release energy
Exergonic reactions (exothermic)
30
Liberation of energy in an exergonic reaction drives an endergonic reaction.
Coupled reactions.
31
The energy given off by the exergonic reaction powers the
Endergonic reaction
32
Removing an electron.
Oxidation
33
Addition of an electron
Reduction
34
*A molecule that loses electron is oxidized.
*A molecule that gains an electron is reduced.
Oxidation and reduction are always coupled reactions.
35
Nicotinamide adenine dinucleotide (N A D).
Role in electron transport
Oxidized form: N A D+.
Reduced form: N A D H.
36
Flavin adenine dinucleotide (F A D).
Role in electron transport
Oxidized form: F A D.
Reduced form: F A D H2.
37
What important role do Both N A D and F A D play an important role in transfer of electrons.
Carrier molecules during bioenergetic reactions.
38
NADH is a ______ agent; it reduces pyruvic acid by giving its hydrogen ions.
reducing
39
NADH becomes_____ to NAD.
oxidized
40
The addition of_______ H+ to pyruvic acid forms NAD and lactic acid
two
41
Catalysts that regulate the speed of reactions
Lower the energy of activation (energy needed to “get started”)
Enzymes
42
Do not “cause” reactions, but regulate the speed at which they occur
Enzymes
43
Factors that regulate enzyme activity
Temperature
•pH
•Each enzyme has an optimal temperature & pH
44
Interact with specific substrates by
Lock and key model
45
Enzymes reduce the energy of activation true or false
True
46
A small rise in body temperature increases enzyme activity.
•Exercise results in increased body temperature.
•Large increase in body temperature (greater than 41°C) can denature enzymes and decrease activity.
Temp influence
47
Changes in pH (increase or decrease) can decrease enzyme activity.
•High intensity exercise decreases muscle pH.
Ph influence
48
Transfer elements of one molecule to another
Transferases
49
Cleave bonds by adding water
Hydrolases
50
Groups of elements are removed to form a double bond or added to a double bond
Lyases
51
Rearrangement of the structure of molecules
Ligases
Isomerases
52
Catalyze oxidation-reduction reactions
Transferases
Oxidoreductases
53
Carbohydrates (C,H,O; ~4 kcal/gram)
Fats (C,H,O; ~9 kcal/gram)
Proteins (C,H,O; ~4 kcal/gram)
54
are organic
•Have carbon “backbones
Macronutrients
55
rules for exercise
Carbs
56
Blood sugar
Glucose
57
Storage form of glucose in liver and muscle.
•Synthesized by enzyme glycogen synthase.
Glycogen
58
Breakdown of glycogen to glucose.
Glycogenolysis
59
Breakdown of glycogen into glucose molecules
Glycogenolysis
60
Breakdown of glucose to generate energy (ATP) pyruvate is the end product of glycolysis
Glycolysis
61
Formation of new glucose from amino acids and lactate.
Gluconeogenesis
62
fuels for exercise Fats
Fatty acids , triglycerides, phospholipids, steroids
63
Primary type of fat used by skeletal muscle.
Fatty acids.
64
Storage form of fat in muscle and adipose tissue.
•Broken down into glycerol and fatty acids via lipolysis.
Triglycerides
65
Not used as an energy source.
Phospholipids
66
Derived from cholesterol-not an energy source.
•Needed to synthesize sex hormones.
Steroids
67
Composed of amino acids
Some (alanine) can be converted to glucose in the liver
Proteins
68
Gluconeogenesis
Others can be converted to metabolic intermediates
•Contribute as a fuel in muscle
Overall, protein is not a primary energy source during exercise (<15%)
Proteins
69
●Glucose is stored in animal cells as
polysaccharide called glycogen.
70
Consists of adenine, ribose, and three linked phosphates
Adenosine triphosphate (ATP)
71
ADP + Pi ATP
Synthesis
72
Formation of ATP
Bioenergetics
73
Phosphocreatine (PC) breakdown
anaerobic
74
Degradation of glucose and glycogen
Glycolysis , aerobic
75
Do not involve O2
•PC breakdown and glycolysis
Anaerobic pathways
76
Require 02
Aerobic pathways
77
Glucose 2 pyruvic acid or 2 lactic acid
•A series of enzymatic reactions
Glycolysis
78
Requires 2 ATP
Energy investment phase
79
Produces 4 ATP, 2 NADH, and 2 pyruvate or 2 lactate
•Occurs in sarcoplasm
Energy generation phase
80
Two Phases of Glycolysis
Energy investment phase, energy generation phase
81
At physiologic pH, H+ dissociates from lactic acid to form lactate.
True
82
At physiologic pH, H+ dissociates from lactic acid to form lactate.
True
83
In order for glycolysis to continue, NADH produced in glycolysis must be converted back to NAD how ?
By converting pyruvic acid to lactic acid
or
•By “shuttling” H+ into the mitochondria
84
Conversion of Pyruvic Acid to Lactic Acid
The addition of two H+ to pyruvic acid forms NAD and lactic acid
85
results from cooperation between the citric acid cycle and election transport chain (both take place in the mitochondria).
Aerobic ATP
86
Completes oxidation of fuels (for example: fats, CHO, proteins) to provide electrons for electron transport chain (via NADH & FADH2).
Citric acid cycle.
87
Energy obtained from electron transport is used to produce ATP at the end of the electron transport chain.
Electron transport chain.
88
Electron transport chain.
Energy obtained from electron transport is used to produce ATP at the end of the electron transport chain.
89
Aerobic Metabolism
The Three Stages
of Oxidative
Phosphorylation
Formation of acetyl-CoA from pyruvate
2. Krebs Cycle
3. Electron transport chain
90
Pyruvic acid (3 C) is converted to acetyl-CoA (2 C)
•NADH is formed
•CO2 is given off
Acetyl CoA “enters” Krebs Cycle
Acetyl Co-A Formation (2 per glucose)
Pyruvate Dehydrogenase Reaction
91
Aerobic ATP production
Electron transport chain
92
•Oxidative phosphorylation occurs in the mitochondria
•Electrons removed from NADH and FADH2 are passed along a series of carriers (cytochromes) to produce ATP.
•Series of redox reactions
•1 NADH results in production of 2.5 ATP.
•1 FADH2 results in production of 1.5 ATP.
Electron transport chain
93
whereby H+ from NADH and FADH2 is combined with O2 to form water and form ATP.
Chemiosmotic hypothesis
94
Aerobic ATP Production
Krebs cycle
95
Acetyl-CoA combines with oxaloacetate (4 C) to form citrate (6 C)
•Citrate is metabolized to oxaloacetate
•Two CO2 molecules given off
•Each cycle produces three molecules of NADH and one FADH
•Also forms one molecule of GTP
•Readily converted to one ATP
Krebs cycle
96
6 NADH, 2 FADH, 2 GTP(→2 ATP) from
Krebs cycle
97
Electron transport chain results in pumping of H+ ions across inner mitochondrial membrane
Results in H+ gradient across membrane
98
Energy released to form ATP as H+ ions diffuse back across the membrane
Can only occur in the presence of oxygen
Must be available to accept electrons
99
Movement of 3 H+ through ATP synthase complex activates conversion of ADP to ATP.
ATP Synthase
100
1 additional H+ is required to transport ATP out of inner mitochondrial membrane
ATP Synthase
101
Oxidative phosphorylation or aerobic ATP production occurs in the
Mitochondria
102
The primary role of the Krebs cycle is to
complete the oxidation of substrates and form NADH and FADH to enter the electron transport chain
103
The end result of the electron transport chain is
the formation of ATP and water. Water is formed by oxygen-accepting electrons; hence, the reason we breathe oxygen is to use it as the final acceptor of electrons in aerobic metabolism.
104
Metabolism is regulated by enzymatic activity. An enzyme that regulates a metabolic pathway is termed a
Rate limit enzyme
105
Triglycerides → glycerol and fatty acids.
•Fatty acids → acetyl-CoA.
•Beta-oxidation.
•Glycerol is not an important muscle fuel during exercise
Fats
106
Broken down into amino acids.
•Converted to glucose, pyruvic acid, acetyl-CoA, and Krebs cycle intermediates.
Proteins
107
Breakdown of triglycerides releases fatty acids
Fatty acids must be converted to acetyl-CoA to be used as a fuel
True
108
Almost 100% of ATP produced by aerobic metabolism
Blood lactate levels are low (<1.0 mmol/L)
Resting O2 consumption (VO2):
Energy requirements at rest
109
The O2 deficit is greater in:
higher intensity exercise.
•untrained individuals
110
-ATP production increases immediately
-Steady state
-Initial ATP production through anaerobic pathways
-oxygen deficit
- Lag in oxygen uptake
-Compensated through anaerobic production of ATP
Rest to exercise
