Exam Two: Learning Objectives Flashcards
1
Q
What are the three major functions animals use energy for?
A
biosynthesis
maintenance
generation of external work
2
Q
Metabolic rate is often estimated by __ consumption (__) but can be measured directly by production of __ (__)
A
oxygen; respirometry
heat; calorimetry
3
Q
Which energy measurement is direct? Which is indirect?
A
respirometry - indirect
calorimetry - direct
4
Q
Discuss water movement through an isolated system.
A
initially water is moving in one direction
eventually directional motion becomes random
heat is produced, water slows down
external energy is needed to keep water flowing
5
Q
What is the difference between closed and open respirometry?
A
open - measures how much oxygen is consumed movement by movement
closed - measure how much oxygen is consumed over a given duration
6
Q
What provides the most direct and accurate measurement of metabolic rate of an organism?
A
heat production (calorimetry)
7
Q
Respiratory Quotient (RQ) =
A
moles of CO2 produced per unit time/ moles of O2 consumed per unit time
8
Q
What is the respiratory exchange ratio for carbohydrates?
A
1.0
9
Q
What is the respiratory exchange ratio for lipids?
A
0.71
10
Q
What is the respiratory exchange ratio for proteins?
A
0.83
11
Q
What is the respiratory exchange ratio (R) of the following equation:
1 mol C6H12O6 + 6 mol O2 -> 6 mol CO2 + 6 mol H2O + 2820 kJ/mol
A
moles CO2 prod/ mol O2 consumed
6/6
=1
12
Q
SDA (specific dynamic action) is __ for protein rich meals compared to lipids or carbs
A
higher
13
Q
Define basal metabolic rate (BMR)
A
used for homeothermic animals, and is measured at their thermoneutral zone, or the temperature range in which it is minimal
14
Q
Define standard metabolic rate (SMR)
A
used for poikilothermic animals and is specific to the temperature at which it is measured
15
Q
There are many ___ for a given individuals (SMR/BMR)
A
SMR
16
Q
__ and __ cause an increase in metabolic rate
A
exercise and feeding
17
Q
The relationship between metabolic rate and body size is __
A
negatively allometric
18
Q
Discuss the energy needs of a species compared to body size
A
metabolic rate is less than proportional to body size of a species
19
Q
Mass specific metabolic rate curves have a __ slope
A
negative
20
Q
A 5g mouse consumes __ oxygen per unit time as a 10 g mouse
A
more than half
21
Q
Many other traits such as __ __ scale with mass
A
heart rate
22
Q
Physiological processes require energy in the form of ___?
A
ATP
23
Q
What are the three ways ATP is generated?
A
phosphogens, anaerobic glycolysis, and aerobic glycolysis
24
Q
Discuss the production of ATP via phosphogens
A
ADP can be phosphorylated directly by reversible stores of phosphate called phosphogens
25
What is an example of reversible stores for phosphogens?
creatine phosphate
26
Describe the process of anaerobic glycolysis
when oxygen is unavailable, a small amount of ATP can be generated by substrate level phosphorylation within glycolysis
27
Describe the process of aerobic glycolysis
oxidative phosphorylation by the electron transport chain can continually generate ATP in the presence of oxygen delivered by breathing or internal stores
28
Which mechanisms of ATP production are steady state?
aerobic catabolism using O2 from the envrionment
29
What mechanisms of ATP production are nonsteady states?
anaerobic glycolysis, phosphagen use, and aerobic catabolism using O2 preexisting in the body
30
Define VO2max
aka aerobic capacity
maximal rate at which an animal can consume oxygen
31
The VO2max determines the maximal rate of sustained __ ___ and thus maximum __ ___
ATP production
exercise intensity
32
T/F: Individuals and species do not differ in their VO2max
false
33
Which mechanism of ATP is best for a sprint?
phosphagens
34
Which mechanism of ATP is best for a marathon?
aerobic/ anaerobic glycolysis aka cellular respiration
35
Relate a chemical equation to the production of phosphagens
creatine phosphate + ADP <- (creatine phosphase) -> creatine + ATP
36
Vertebrae muscle contains molecules that temporarily store __ __ __ donated from ATP
high energy phosphates
37
Discuss the energy stored at the rate at which ATP is generated for phosphagens
energy stored in phosphogen fuels can only sustain exercise for a few seconds, but it can generate ATP at very high rates (i.e. high power)
38
What do vertebrates use for phosphagen? Invertebrates?
verts - creatine phosphate
inverts - arginine phosphate
39
What are the four steps of aerobic metabolism?
glycolysis
intermediate step
the Krebs cycle
oxidative phosphorylation
40
What is generated during glycolysis?
2 net ATPs, 2 NADHs and 2 pyruvates
41
What is generated during the intermediate step?
2 NADHs
42
What is generated during the Krebs cycle?
Generates 2 GTPs -> 2 ATPs, 6 NADHs, and 2 FADHs
43
What is generated during oxidative phosphorylation
generates roughly 34 ATPs in theory
44
Anaerobic glycolysis; When O2 is unavailable, building NADH is __ __, as the __ __ __ is disabled
not useful
electron transport chain
45
Glycolysis can be used to generate __ amounts of __ without the use of __
small; ATP; mitochondria
46
Anaerobic glycolysis; because the ETC is not consuming ___, ___ becomes scares, compromising the ability to run ___
NADH
NAD+
glycolysis
47
Anaerobic glycolysis regenerates __ using ___ __ __
NAD+
lactate dehydrogenase (LDH)
48
Anaerobic glycolysis: using __, pyruvate is converted to __ in order to maintain redox balance
LDH
lactate
49
What requires metabolic processing?
lactate, unlike CO2 and H2O
50
Lactate is converted back to __ only after __ __ to tissues is resumed
pyruvate; O2 delivery
51
__ is required for the metabolism of __
O2; lactate
52
Describe the percentage of ATP made by glucose from glycogen stored in muscles over exercise
Roughly 50% at beginning, 25% after two hours, 0% around 3.5 hours
53
Describe the percentage of ATP made by glucose brought to muscles by blood over exercise.
starts at 10% then increases over time
54
Describe the percentage of ATP made by fatty acids brought to muscles by blood over exercise.
Starts at 40% and slowly increases over time
55
Where does energy come from during a 100 m sprint?
ATP from anaerobic glycolysis > ATP from phosphagen > ATP from aerobic catabolism using glycogen and glucose
56
Where does energy come from during a 1500 m run?
ATP from aerobic catabolism using glycogen and glucose > really small amount of ATP from anaerobic glycolysis
57
Where does energy come from during a marathon?
ATP from aerobic catabolism using glycogen and glucose >ATP from aerobic catabolism using lipids
58
What is the function of myoglobin?
vertebrate skeletal muscle also contains a type of hemoglobin that stores O2 internally by directly recruiting O2 molecules from blood hemoglobin
59
What enables many vertebrates to have the ability to run aerobic glycolysis for a few seconds without O2 delivery to tissues?
myoglobin
60
What are the two kinds of muscle fibers?
Fast glycolytic fibers (FG) and slow oxidative fibers (SO)
61
Fast glycolytic fibers contract __, can generate lots of __, primarily fueled by __ __ and thus have high levels of __ __ (LDH) and __ mitochondrial volume
quickly; power; anaerobic glycolysis; glycolytic enzymes; low
62
Slow oxidative fibers contract relatively __ are primarily fueled by __ __ so they have high levels of __ __ and lots of __ and __
slowly; oxidative metabolism; aerobic enzymes; mitochondria; myoglobin
63
High levels of __ and __ make SO fibers more resistant to fatigue
myoglobin; mitochondria
64
FG is shown as __ in the picture and SO is shown as __
light; dark
65
Describe aerobic and anaerobic cooperation of light submaximal exercise
Actual O2 much smaller than maximal, minimal oxygen deficit and excess post exercise oxygen consumption, takes short time
66
Describe aerobic and anaerobic cooperation of heavy submaximal exercise
actual O2 uptake just below theoretical O2 demand - relative oxygen deficit and excess postexercise oxygen consumption, takes medium amount of time
67
Describe aerobic and anaerobic cooperation of supramaximal exercise
actual O2 uptake meets theoretical O2 demand - oxygen deficit and excess post exercise is excessive, takes long time
68
Two species of __ (goldfish and carp) run the __ __ reaction in reverse - converting __ to __ and __
fish; alcohol dehydrogenase
lactic acid; ethanol and CO2
69
Goldfish can run __ __ indefinitely, as __ and __ can be eliminated much easier than __
anaerobic glycolysis
ethanol; CO2
lactate
70
Define heat
a form of energy; amount of energy a substance contains as a result of its random molecular motions
71
Define temperature
measure of the intensity of random molecular motions of a substance (heat)
72
T/F: A large object and a small object can have the same temperature, but different amounts of heat energy
True - the amount of matter matters
73
Heat (__) flows from areas of __ temperature to areas of __ temperature, regardless of the amount of heat in both areas
energy
high
low
74
What are the four kinds of thermoregulatory classifications?
endothermy, ectothermy, homeothermy, and poikilothermy
75
Define endothermy
body temperature is generated from within (metabolic processes)
76
Define ectothermy
body temperature is determined from the environment
77
Define homeothermy
body temperature is relatively constant
78
Define poikilothermy
body temperature is variable
79
There are more __ on earth than homeotherms
ectotherms
80
Some ectotherms exhibit __ regulations
behavioral
81
Define stenothermal
an animal that can function only over a relatively small range of temperatures
82
Define eurythermal
an animal that can function over a relatively broad range of temperatures
83
What are 5 ways animals exchange heat with their environment?
radiation (sun, animal, bush, sky)
Conduction
Convection
Cutaneous and respiratory evaporation
84
Describe the heat regulation of an antelope jackrabbit
may radiate heat from large ears to save on evaporative loss by panting
85
Metabolic rate increases approximately __ with increasing __ temperature
exponentially; body
86
Which thermoregulator demonstrates acclimation in a laboratory setting?
ectotherms
87
Species acclimated to colder temperatures have a higher average __ __ at any give body temperature
metabolic rate
88
Define compensation
kind of acclimation that moderates the acute response to temperature
89
If lizards are kept at the new temperature, they would show __, over the long term, to the value __ to being moved to a new environment
compensation, prior
90
Why does acclimation take so long?
physiological changes occur in relative amounts at the cellular level
91
Enzyme substrate affinity is similar over a constant __
temperature
92
Enzyme substrate affinity generally __ with __ temperature
decreases; increasing
93
How do ectotherms regulate freezing? (two ways)
they can tolerate it or prevent it
94
Describe tolerance of ectotherms to freezing
tolerance involves managing ice crystal formation; self-limiting process due to osmosis and colligative properties of water
95
Describe prevention of ectotherms freezing.
involves supercooling and antifreeze
96
What are the two types of antifreeze?
colligative and non-colligative
97
Define supercooling
managing ice-nucleating agents
98
Define colligative antifreeze
solutes depress freezing point
99
Define non-colligative antifreeze
interact with ice crystals to prevent spreading of their formation
100
Birds and mammals __ their body temperature by mainly __ means but can also use ___ means
regulate
physiological; behavioral
101
T/F: Birds and mammals are less independent from environmental temperatures than ectotherms
false
102
Birds and mammals: cellular functions occur at a relatively __, __ temperature
constant, reliable
103
What is the deep body temperature for placental mammals?
37°C
104
An endotherm's metabolic rate __ in __ and __ environments
rises
hot; cold
105
What is the thermoneutral zone?
determines rate of dry heat transfer and therefore the metabolic rate, from Tb to Ta
106
What is the linear heat equation? (for metabolic rate)
M = C(Tb-Ta)
where c = thermal conductance
107
Insulation and conductance are __ proportional
inversely
108
As temperature drops within the TNZ, insulation is?
increased
109
What is a way to acclimatize to winter?
increase insulation
110
How does peak metabolic rate and thermo neutral zone change during winter when more fur is added?
peak metabolic rate remains the same
TNZ is increased
111
__ ___ ___ (BAT) is __; __ short circutis the __/__ synthase
brown adipose tissue
thermogenic
UCP1; ETC/ATP
112
BAT is found in which kind of animals?
cold acclimated animals, hibernators, and newborns
113
Increasing peak metabolic rate, often with more ___, is a response to __, where __ remains the same
BAT, cold, insulation
114
Countercurrent heat exchange: outgoing, __ blood gives heat to __ venous blood by virtue of the __ of vessels
arterial, incoming, proximity
115
How is hibernation an adaptation to regulating body temperature?
allows body temp to drop close to ambient temp for several days in winter
116
Hibernation is common in __ and rare in__
mammals; birds
117
Define estivation
hibernation in summer for endotherms
118
What is a daily alternative of hybernation?
torpor
119
Daily torpor is used by many small ___, to escape high __ demands of each night
endotherms; energy
120
Controlled hypothermia is __ __
facultative ectothermy
121
What is a common strategy of cooling about the TNZ?
enhancing evaporative cooling which increases heat transfer to extremeties
122
What are mechanisms of enhancing evaporative cooling?
gular fluttering, panting, and sweating
123
What are some examples of behavioral thermoregulation?
moving to shade, changing orientation to the sun, burrowing
124
How do homeotherms survive in hot environments?
cycling body temperature and hyperthermia
125
Describe cycling of homeotherms
allowing body temperature to rise above set point during the hot day, and drop below set point at night
126
How does cycling of body temp help temperature regulation of homeotherms?
reduces water loss by evaporative cooling during the day, conducting stored heat to ground during the night
127
Hyperthermis is common in __ and rarer in __
birds; mammals
128
How does hyperthermia help homeotherms?
allows body temperature to increase to profoundly high temps (decreases Tb-Ta and therefore reduces heat gain and need to cool by evaporative means).
129
Permeability of ion channels determines?
membrane resistance and capacitance
130
Define capacitor
charge-separating device
131
Membrane potential (Vm) is due to __ of __ near the __, even though the bulk solution is electrically __
gathering, ions, membrane
neutral
132
Vm is approximately?
-65 mV, negative on the inside relative to the outside
133
Why is Vm not zero?
selective permeability of the membrane to ions of K+, drives Vm in cells
134
Where does the -65 mV resting membrane potential come from?
Nernst eq - concentration differences of only one ion
Goldman eq - accounts for actual permeability of all the ions on either side of the cell membrane
135
Define the nerst equation
electrochemical equilibrium for an ion species - assumes the ion would come to equilibrium (100% permeable)
136
Define the goldman equation
calculates the membrane potential when more than one ion is permeable
137
What are the three most permeable ions?
K+, Na+, and Cl-
138
In resting state, __ is the most permeable ion, and thus the resting membrane potential is close to __
K
Ex - electromotive forces (Vm of Ion)
139
The __ of K is so much __ than that of __ or __, that K __ dominates the membrane potential
permeability; higher
Na, Cl
flux/ current
140
Adjusting ion __ can change __
permeabilities; Vm
141
Changing __ can produce a?
Em (Vm)
action potential
142
Define depolarization
moving towards zero, less negative
143
Define hyperpolarization
moving away from zero, more negative
144
Describe the stages of an action potential
resting membrane potential -> rising phase -> falling phase -> recovery
145
Describe the membrane during the resting membrane potential
only K+ leak channel is open, voltage gated Na and K are shut
146
Describe the membrane during the rising phase
K leak channel is open, Voltage gated Na is. open and allowing Na inside the cell, voltage gated K is closed
147
Describe the membrane during the falling phase
K leak channel is open, voltage gated Na channel inactivates and voltage gated K opens, letting K out of the cell
148
Describe the membrane during the recovery period
K leak channel and voltage gated allows K in and out of the cell, voltage gated Na channel is closed
149
Propagation rate of action potentials is influenced by?
temperature, axon diameter, and myelination
150
How does temperature affect propagation rate?
higher temp causes faster conduction
151
How does axon diameter influence propagation rate?
larger axon diameter, faster conduction
152
How does myelination impact propagation rate?
myelin speeds conduction enormously
153
Spiking neurons have long __ and produce __ ___
neurons; action potentials
154
Spiking neuron: all or non action potentials are __ into __ __ of neurotransmitters at the __ terminals
translated; graded secretion; axon
155
What is found at the input of a spiking neuron?
graded potential
action-potential encoding
156
What happens are the output of a spiking neuron?
action-potential propagation
neurotransmitter secretion
157
Non-spiking neurons are _ and produce __ __
shorter;
no action potentials
158
What happens at the input of a nonspiking neuron?
graded potential
159
What happens are the output of a nonspiking neuron?
graded potential, neurotransmitter secretion
