DPT Physiology Exam 1
In norma mammalian nerve fibers, the potential difference for Na+ is about
+61 mV
So, if the membrane potential were only permeable to Na+, the membrane potential would be
+61 mV
What is the resting membrane potential of muscle?
-80- -90 mV
According to dr. stock, the two reasons resting membrane potential are
-90 mV is K+ leak channels and the Na+/K+ potassium pump
If the membrane were permeable to only K+, the membrane potential would then be
-94 mV
In normal mammalian nerve fibers, the potential difference for K+ is about
-94 mV
The velocity of action potential conduction in nerve fibers varies from as little as _____ m/s in small unmyelinated fibers to as great as ______ in large myelinated fibers
0.25 m/s (very slow) 100 m/s (very fast/ they hop)
For example, urine volume can be as low as ______ in a dehydrated person or a s high as _____ in a person drinking a tremendous amount of water
0.5 L/day 20 L/ day
Resting blood lactate :
0.5-2.2 mmol/L
The resting phase is step ____ out of four in excitation contraction coupling
1
Marbling scores in muscle range from
1-12
Transcellular fluid makes up about _____ and includes what?
1-2 L Synovial, peritoneal, pericardial, intraocular spaces, as well as cerebrospinal fluid
Propriospinal fibers travel up and down the cord for
1-2 segments
Every ____ along the axon there is a space, referred to as the ____
1-3 mm node of ranvier
What is the druation of action potentials in skeletal muscle fibers?
1-5 ms, which is five times as long as in large myelinated nerves
what is Na the most abundant?
1. Only Na and K ions are present in large concentration 2. Negative potential on the inside of the muscle membrane pulls the positive sodium ions to the inside and prevent the efflux of potassium when they try to leave
Establishing resting membrane potentials in nerve fibers is under three conditions
1. When the membrane potential is caused entirely by K+ diffusion alone 2. When the membrane potential is caused by diffusion of both Na+ and K+ ions 3. When the membrane is caused by diffusion of both Na+ and K+ ions plus pumpint of both these ions by the Na+ K+ pump
From these statistics what can we conclude?
1. larger muscles have lesser firing rates but greater max recruitment threshold 2. smaller muscles have greater firing rates and lesser max recruitment threshold
The ability to produce force is controlled by
1. the recruitment of motor units 2. The manipulation of firing rates
After entering the cord, they travel in two directions:
1. transmitted to higher centers 2. They synapse to elicit motor reflexes
Some of the different issues that cause ECF and ICF volumes to change markedly include: 1. Excess ingestion or renal retention of ____ 2. _____ 3. Intravenous ____ of different types of solutions 4. Loss of large amounts of fluids from the ____ 5. Abnormal amounts of fluid by ____ or through the ____
1. water 2. Dehydration 3. infusions 4. GI tract 5. sweating; kidneys
what are the two means by which acetylcholine is removed?
1.Most destroyed by acetylchoineesterase 2. Small amount diffuses out of the synaptic space and is no longer available to act on the muscle fiber membrane
The total duration of the calcium pulse in the usual skeletal muscle fiber lasts
1/20 of a second
About how much fluid is in the space outside cells and is called what?
1/3; extracellular fluid
How much of the muscle does the muscle fiber span?
1/4
The Na+K+ pump requires about ____ of typical cells energy and up to ___ of neuron's energy
1/5; 2/3
Full excitation of the T tubule and sarcoplasmic reticulum system causes enough release of Ca ions to increase the concentration in the myofibrilar fluid about ____ required to cause a muscle contraction
10 x
The rate of ATP usage can increase
10 x above the resting level during maximal exercise
How much percentage leeway is there in the chart of ranges?
10%
Max molecular weight of particles that can diffuse regularly is ___, glucose is ___
100 180
Liver contains ____ of glycogen storage
100 g
The total amount of water that diffuses in each direction through the red blood cell membrane during each second is about
100 x as great as the volume of red blood cell itself
Max exercise intensity:
100% carbs as anaerobic metabolism becomes predominant source of energy at high intensity
About 1 person per _____ in the US is thought to have this disease. The male to female ratio is ____
1000 2:1
When the pancreas secretes large amounts of insulin the rate of glucose transport into most cells increases to
10x or more
How many liters does the interstitial fluid account for?
11 L
Plasma sodium is less than or equal to ___, which leads to ____
115 mmol/L; seizures, coma, death
The FDI, a small muscle in the hand contains _____ motor units its firing rates are reported in the range of ____ with a max recruitment threshold of ____
119 motor units 47-92 pulses per second 55% max voluntary contraction
Rigor mortis peaks approximately ___ after death and disappears ____ after death due to breakdown of muscle
12 hours 48-60 hours
When a nerve impulse reaches the NMJ, how many vesicles of acetylcholine are released form the terminals into the synaptic space?
125
In the case of glucose, at least _____ of a family of membrane proteins called GLUT have been discovered
14 members
Glycolysis occurs in moderate intensity exercise lasting
15 s-2 minutes
In hypernatremia, plasma sodium is greater than or equal to
158 mmol/L
Simple diffusion occurs in a
1:1 ratio; greater concentration = greater speed
Excitation contraction coupling is step ____
2
In shuffling pyruvate into mitochondria, ___ pyruvates are produced and then proceeded through the ____ into the mitochondria
2 krebs cycle
One myosin molecule is comprised of ____ heavy chains and ___ light chains
2 ; 4
For example; a solution of 1 mol/L NaCl corresponds to an osmolarity of
2 osmol/L Osmolarity is the number of MOLE that contribute to osmotic pressure; NaCl is ionizable. Thus, NaCl has one mol of Na + one mol of Cl = 2 moles / 1 L of water
I converting pyruvate to lactate, ____ pyruvates are reduced to ____
2 pyruvates 2 lactates and 2 H+ ions
In 20 grams of protein, there are
2-3 grams of leucine
How long is your rapid phase?
2-3 minutes
Capillaries have ___ more pressure on the inside of the cell than the outside
20 x
What percent of total body mass is the extracellular fluid?
20%
Small muscle mass: Whole body routine:
20-25 g of protein 40 g of protein
What should a typical daily protein distribution look like:
25 g of protein at each meal and leucine dispersion
How many erythrocytes are in each human?
25 trillion
Exercise blood lactate:
25-30 mmol/L
Bioimpedance spectroscopy uses how many different frequencies?
256
In the study, muscle length was ____ on average, and the fiber length ended up being about ___ of that
27 cm 1/3
How many liters does the intracellular fluid account for?
28 L
____ inside the cell will go out _____ outside the cell will go in
3 Na+ 2 K+
The Na+ K+ pump has binding sites for ____ on the inside of the cell and ____ on the outside of the cell
3 Na+; 2 K+
Fore every one g of glycogen we store ___ of water
3-4 g
Post exercise phosphagen repletion can occur in a relatively short period of time; complete resynthesis of ATP appears to occur within _____ and complete creatine phosphate resynthesis can occur within 8 minutes
3-5 minutes
What is the velocity of conduction of the skeletal muscle fibers
3-5 ms, about 1/13 the velocity conduction in the large myelinated nerve fibers that excite skeletal muscle
Success or failure of most human movement is determined in less than
300 ms
How many of these vesicles collect in the nerve terminals of a single skeletal muscle end plate?
300,000
Interneurons are ___ more abundant than anterior motor neurons
30x
According to the ATP chart, during a 3 second spring,
32% is intramuscular ATP 55% is intramuscular PC 10% is Lactate source (anaerobic glycolysis) 3% is from aerobic metabolism
At rest, _____ of ATP is derived from carbs and ____ from fat
33% ; 66%
A lean adults has ____ adipocytes
35 billion .4-.6 micrograms of triglycerides each 130,000 kcal stored
100 g of glucose can increase protein synthesis by ____ but does not come close to ___ of EAA
35% 6g
In women, Hematocrit accounts for
36%
The vastus lateralis exhibits relatively low firing rates with a max value reported in the range of _____ and a max recruitment threshold of ____ of the max voluntary contraction force level
37-50 pulses per second 85%
How many liters does plasma account for?
3L
In Men, hematocrit accounts for
40%
What percent total body mass is the intracellular fluid?
40%
Muscles contain ___ of glycogen storage
400 g
The tibialis anteior a smaller lower limb muscle contains ____ motor units whose firing rates exhibit larger values reportedly in the range of _____ and max recruitment threshold of ____
445 motor units 40-58 pulses per second 70% maximum voluntary contraction
An extremely obese has as many as ____ that amount of adipocytes
4x .8-1.2 micrograms of triglycerides each 1,000,000 kcal stored
The average blood volume is about
5 L
Hydrogen variations are usually less than
5 nanometers
Single frequency BIA is performed at a frequency of
50 kHz
About ___ of blood is plasma; ___ Red blood cells
50%; 40%
there are ___ different protein containing compounds in the body and ____ of them are in skeletal muscle
50,000 65%
At rest, the conductance of K+ ions is ____ greater than the conductance for Na+
50-100
Motor neurons are locate din the anterior portion of the cord. Motor neurons are ______ bigger than other neurons
50-100%
In the phosphagen system, ATP concentrations may only slightly decrease or decreases by up to _____ of the pre exercise levels during experimentally induced muscle fatigue
50-60%
Creatine phosphate can decrease markedly ____ during the first state (5-30 seconds) of high intensity exercise and can be almost eliminated as a result of very intense exercise to exhaustion
50-70%
most muscles are a ____ mix of type one and type two muscle fibers
50/50
During early stages of action potential, Na+ channels become activated to allow a ____ increase in Na conductance
5000x
How much of the adult human body is fluid
60%
In a normal 70 kg adult male, the total body water is about how much of total mass?
60%
BMR accounts for ____ of total calories per day
60-75%
Endurance trained:
65-80% of max oxygen consumption (thus can exercise at high intensity before reaching the threshold )
____ of the lactate aerobically metabolized, while ____ synthesize glucose and ____ synthesize gluconeogenic amino acids
70% 20% 10%
How many other cells perform different functions?
75 trillion, total = 100 trillion
Phosphagen is created during very high intensity exercise, lasing
8-10 seconds
Of your total body fat, ___ is adipose and ____ is other lipids and fats
80% 20%
Thus, ____ of monosaccharides are glucose
95%
Glycogen = 1% of FFM which ends up being
<1% of muscle
What is botulinum toxin?
A bacterial poison that decrease the quantity of acetylchoine released by the nerve terminals
Blood sodium varies by
A few milimoles/liter with large changes in sodium intake
In impedimed SFBF testing, Electrodes are at
A fixed distance (5 cm)
Colloid osmotic pressure is
A form of osmotic pressure exerted by proteins, notably albumin, in a blood vessel's plasma (blood/liquid) that usually tends to pull water into the circulatory system
Disease is
A state of disrupted homesostasis
Ions, nutrients, etc are normally regulated within
A tight range of valus
Creating phosphate donates phosphate groups to form ATP from
ADP
The 2nd ATP replaces ____ and allows myosin head to detach from actin binding site
ADP
Intramuscular PC stores increased using ____ from aerobic metabolism, blood acidity is reduced
ATP
The more intense we exercise, the more rapidly we produce ____, the shorter the time is to produce it
ATP
What are the chemical reactions for the phosphagen systems ?
ATP --> (using myosin ATPase) --> ATP + Pi + energy ADP + creatine phosphate --> (with creatine kinase) --> ATP + creatine
Cross bridge flexion is caused by ____ breakdown to ____
ATP --> ADP via mATPase enzyme on the myosin head
Depletion of ____ and ____ does not appear to be the primary cause of decreased muscle force and fatigue
ATP and PC
Phosphagen (also called the ATP PC system) is formed when
ATP and creatine phosphate without oxygen
The pump uses activated ______, which uses ATP to break down to ____
ATPase ADP and Pi
Alpha motor neurons are large type _____ fibers
Aa
The channel is constricted, until two ___ attach to the two ____
Acetylcholine molecules Alpha sub unit proteins
What enzyme destorys eacetylcholine a few ms after it has been released from the synaptic vesicles?
Acetylcholinesterase
Lactate not cause acidity:
Acidity comes from ATP breakdown which increases H+ concentrations; thus acidity itself hurts performance
On the arms, the blue electrodes go on the
Acromial Process
What is steady state?
All energy needed is provided by aerobic metabolism
In hyponatremia, neurologic function is
Altered (confusion, seizures)
How does Myastenia gravis work?
Antibodies attack acetylchoine receptors at the post synaptic junction, muscle fiber depolarization does not occur
On the foot, the superior electrode is placed
At the level of the lateral malleoli
On the hand, the superior electrodes are placed
At the level of the ulnar styloid process
The vesicles are transported by ___ that streams through the core of the axon from the cell body in the spinal cord to the NMJ
Axoplasm
Gamma motor neurons are a smaller type of ____ fibers
Ay
How is arterial blood pressure regulated?
Baroreceptors
Despite different functions, all cells have the same
Basic composition
A practical tip: longer rest periods between sets and events =
Better recovery and performance
The ____ electrode must be placed 5 cm from the blue
Black
The electrode that bisects the malleoli is
Blue
Only the ____ electrodes are moved for the arm and leg measurements; all other electrodes stay in place and are constant
Blue and yellow
Total body water =
Body mass x .0.60
Plasma =
Body mass x 0.043
Interstitial fluid =
Body mass x 0.157
Extracellular fluid =
Body mass x 0.20
Intracellular fluid =
Body mass x 0.40
At high frequencies however the current passes through
Both the ICF and ECF
Define catabolism:
Breakdown of large proteins / fat/ carbohydrate molecules into smaller products yielding energy release
Visceral adipose tissue is realated to
CVD
Once the calcium ions have been released from the SR and diffused among myfirbris, mucle contraction continues as long as
Ca concention is high
The T tubule action potential causes release of ___ inside the muscle fiber
Ca ions
At rest, there is little ____ in the myofibril
Ca2+
In excitation contraction coupling, an action potential causes an increase in ____ in the myofibril
Ca2+
Rigor mortis has nothing to do with
Ca2+
When an action potential arrives in the nerve terminal, it opens ___ in the membrane of the nerve terminal beacuse of the abundance of ___
Calcium channels voltage gated calcium channels
What protein binds up to 40 x more calcium?
Calsequestrin
The respiratory system operating in association with the CNS regulates the concentration of
Carbon dioxide
What can cross the lipid bi layer on its own?
Carbon dioxide Oxygen Nitrogen
If a cell is placed in a HYPOtonic solution,
Cell concentration will be higher, water will rush into the cell, the cell will swell
Hyponatremia consequence is seen by
Cell swelling
What is an effector?
Changes values of controlled variable
Simple diffusion utilizes
Channel proteins
What is an example of positive feedback?
Childbirth
What does not pass thorough the channel?
Cl- ions; there is a strong negative charge in the mouth of the channel that repel the negative ions and attract the positive ones
What is protein digestibility corrected amino acid score?
Compares the AA profile of a specific dietary protein with the essential human AA requirements established by the food and agriculture organization corrected for digestibility
The Nernst equation provides balance between
Concentration and charge
Titn
Connects myosin to the z line
pyruvate may proceed in one of two directions:
Converted to lactate or shuttled into the mitochondria
The ____ is the shuttling of lactate to the liver whereby lactate is oxidized to form glucose
Cori cycle
Subjects were randomly assigned to either a
Cr or a Placebo group
Adding hypotonic solution to the ECF
Decrease the overall osmolarity of the solution (osmol/L, you are adding concentration lower than that of the starting concentration), increase the volume of the ECF, increase the volume of the ICF (water will rush into the cell due to a higher concentration on the inside than the outside)
Hyponatremia
Decreased sodium concentration relative to water
Concerns regarding _____ had been previously described in the mainstream press
Dehydration
Neurons consists of three basic components
Dendrites Cell bodies Axon
Explain how it is an example of positive feedback
Depolarizatoin starts, becomes more +, continues to become more positive
What is a sensor?
Detects controlled variable
What is an integrator?
Detects differences between set poitn and actual value of a variable
Total body water, ECT, and ICW volumes were assessed using
Deuterium oxide and sodium bromide dilution analyses
Electrolyte intake is governed by
Dietary habits
Dr stock said that the cross section of muscle was a key illustration.
Different colored muslce fibers, groups are innervated collectively by different neurons Grouped together biologically identical preferentially active different motor units without activating the other
The continual movement of molecules among one another in liquids or in gases is termed
Diffusion
Diffusion occurs
Down a concentration gradient
What is the relative refractory period?
During this period of time, a second action potential can be generated, but it takes greater stimuli than normal
In bioimpedance spectroscopy, impedance at zero frequency represents what?
ECF
What is the nernst equation?
EMF (mV) = +- 61 log (Ci / Co)
What is the K+ Nernst equation?
Ek = -61 x log Ki/Ko
If Ko = 4 mM and Ki = 140 mM, then
Ek = -61log (140/4) Ek = -61log (35) Ek = -94 mV
The method involves passing an extremely low strength _____ through the body and measuring the _____
Electrical current impedance to the flow of this current
The pump is said to be _______ because it creates an electrical potential across the cell membrane
Electrogenic
There is a time difference between the onset of electrical activity of the muscle and the onset of force/tension. This is known as
Electromechanical delay
These limited frequency devices employ _____ to estimate subject results
Empirical linear regression models
Using the Nernst equation, if Nao = 142 mM and Na i = 14 mM,
Ena = -61 log (14/142) Ena = -61log (0.1) Ena = +61 mV
Unlike diffusion, active transport reqruies
Energy (ATP)
There are three types of connective tissues in muscles:
Epimysium Perimysium Endomysium
Red blood cells are also called
Erythrocytes
Foods lack
Essential amino acids
Lactate threshold:
Exercise intensity at which blood lactic acid exceeds resting concentration
For each miliosmole of impermeant solute, about 19.3 mmHg of osmotic pressure is
Exerted across the cell membrane
Bicarbonate (anion) is more abundant in the
Extracellular fluid
Chlorine (anion) is more abundant in the
Extracellular fluid
Sodium (cation) is more abundant in the
Extracellular fluid
Body fluid is distributed mainly between two compartments
Extracellular fluid (made up of plasma and interstitial fluid) Intracellular fluid
What types of transport utilize carrier proteins?
Facilitated diffusion Active transport
The nonsignificant increase we observed accounted for 55.4% of the increase in TBW volume, which is
Fairly consistent with normal fluid distribution (approximately 2/3 of the TBW is intracellular)
Define bioenergetics?
Flow of energy in a biological system
Fluid and electrolyte balances are necessary in the long-term to maintain life. The balances are as follows:
Fluid loss = fluid intake Electrolyte loss = electrolyte intake
What is the purpose of synapsin anchoring the acetylcholine vesicles to the cytoskelton?
Free acetylcholine vesicles from the cytoskeleton, moves them into the active zone of the presynaptic neural membrane
Who introduced the term milieu interieur?
French physiologist Claude Bernard
Some devices will offer a choice of three on board algorithms: ____, therefore improving the accuracy of measurement at 50 kHz
General, child, obese
What is secreted when blood glucose is too low?
Glucagon
_____ typically cross the cell membranes via facilitated diffusion
Glucose and amino acids
How did Dr stock describe co transport?
Go on a trip and you have to bring a friend with you, you move in the same direction
In the formation of acetylcholine, small vesicles are formed by the
Golgi apparatus
____ moves across a cell membrane easily
H2O
How does K+ get through a potassium channel?
Have tetrametic structure Four identical protein sub units surrounding central ore and pore loops at the top that form a narrow selectivity filter Carbonyl oxygens line filter K+ interacts with carbonyl oxygens and shed water and K+ passes
These algorithms have been determined from ___; though one algorithm is not suitable for all subjects
Healthy subjects
Rapid swelling can cause ____. Because the skull is rigid, the brain cannot increase its volume by more than ____ without being forced down the neck (herniation)
Herniation 10%
This is related to interval training or many aerobic sports, where
High intensity bouts are accompanied by lower intensity recovery periods
____ is the most common electrolyte disorder an may occur in ____ of hospitalized patients
Hyponatremia 15-25%
In women, what are the Cross sectional area fiber type ratios?
I = IIA = IIB
In women, what are the fiber type percentages?
I > IIA> IIB
Aerobic enzyme content is greater in
I > IIa > IIx
Capillary density is greater in
I > IIa > IIx
Mitochondria content is greater in
I > IIa > IIx
Myoglobin is greater in
I > IIa > IIx
In the sliding filament theory, the ____ shortens, bu the ____ length does not change
I band A band
In men, what are the fiber type percentages?
IIA > I > IIB
In men, what are the Cross sectional area fiber type ratios?
IIA > IIB > I
Creatine kinase concentrations are the highest in
IIX muslce fibers
Acute force production is greater in
IIx > IIa > I
Endurance training increases
IM Glycogen
What is a set point?
Ideal value of controlled variable
Many solutes are relatively
Impermanent to cell membranes
Cell membranes are almost completely
Impermeable to many solutes
Hypernatremia
Increased sodium concentration relative to water
This process is known as
Indicator dilution principle
What is an efferent pathway?
Information from integrator to effector
What is an afferent pathway?
Information from sensory to integrator
Water is added to the body by
Ingested food or liquid (2100 ml/day) Synthesized in the body by oxidation of carbohydrates (200 ml/day)
Most of that fluid lies where and is known as what?
Inside cells; intracellular fluid
Water is found both
Inside the cells (ICF) Outside the cells (ECF)
What is secreted when blood glucose is high?
Insulin
Where is acetylchoine emptied to in the synaptic space?
Into Acetylchoine gated ion channels, which have acetylcholine receptors in the muscle fiber membrane. Located at the mouth of the subneural clefts lying immediately below the dense bar area
If the increase in body water presents inside the cells only, this could disrupt the balance between
Intracellular and extracellular fluids
Calcium (cation) and Magnesium (cation) summed up are more abundant in the
Intracellular fluid
Phosphate and organic anions are more abundant in the
Intracellular fluid
Potassium (cation) is more abundant in the
Intracellular fluid
Proteins (anion) are more abundant in the
Intracellular fluid
The key driver in the ATP source during 3 second spring is
Intramuscular Phosphocreatine
All different types of gases / ions have no help crossing the membrane. This includes
Ions, glucose, Water and urea.
H zone:
Just myosin
_____ have a selectivity filer that allow it to move in and out of cells
K Leak channels
This is especially true for
K and Na
Fractions of a ms after Na channels become inactive,
K channels become activated but their effect is much slower
Thus, Na entered is counteracted by
K leaving
Electrolyte output is regulated mainly by the
Kidneys
Fluid output is regulated mainly by the
Kidneys
What is the list of things that assist in "output" of body fluids?
Kidneys Lungs Feces Sweat Skin
Define simple diffusion
Kinetic movement of molecules or ions occurs through a membrane opening or through inter molecular spaces without any interaction with carrier proteins in the membrane
The acetyl CoA enters the
Krebs cycle
The formation of lactate is catalyzed by the enzyme
Lactate dehydrogenase
Unhydrated K+ are too
Large
Factors that affect IM glycogen in weight and sprint activities:
Length of training program Type of training
Define refractory period
Limit frequency of action potentials
The membrane consists of a
Lipid bilayer Protein molecules in the lipid that penetrate all the way through the membrane
In simple diffusion, lipid soluble molecules move readily across cell membranes. The rate of diffusion depends on
Lipid solubility
All the measurements were reassessed immediately after the
Loading and maintenance phases
The Cr group ingested 25 g/d of Cr for seven days, called the ____, and 5 g/d for the remaining 21 days, called the ____
Loading phase Maintenance phase
What is homeostasis?
Maintenance of nearly constant conditions in the internal environment
What is protein efficiency ratio?
Measures the ability of a protein to support the growth of a weaning rat; calculated as the ratio of the weight gained to the amount of protein consumed
Define threshold potential
Membrane potential at which the action potential is initiated
What are examples of compounds that have similar effects on the muscle fiber as acetylcholine?
Methacholine Carbachol Nicotine
In type I, there are more _____ that support long term ATP production
Mitochondria
Define primary active transport
Molecules are pumped against an electrochemical gradient at the expense of energy (ATP)
Stimulus
Muscle contraction (tension)
The hydrogen atoms are carried by
NADH and FADH2 to the electron transport chain
What is the most abundant ion that flows through the channel?
Na
What travels through the channel?
Na K Ca
What are pairs of antiporters/countertransporters given in class?
Na and Ca Na and H Na and HCO3- Cl and H+
What are examples of symporter pairs given in class?
Na and amino aicsd Na and glucose Na and 2HCO3- basically, Na bound to a hitch hiker
The absolute refractory period is the time it takes the
Na channel to go from the inactive state to the resting state
K channels open at roughly the same time that
Na channels close
In the Na+K+ pump,
Na is high on the outside
The pump is responsible for maintaining
Na+ and K+ on the outside and inside of cells, respectively, as well as establishing a negative electrical voltage inside the cells
if a 32 year old male use anabolic steroids and now his hypothalamus and pituitary inhibit natural production, what is this an example of?
Negative feedback
Sodium channels are lined with _____ that literally pull the Na+ ion away from its water shell
Negatively charged amino acids
What are examples of drugs that inactivate acetylcholinesterase?
Neostigmine Physostigmine Diispropylfluorophosphate
What drug is given to people with myastenia gravis?
Neostigmine, or some other anticholinestase drug, which allows larger than normal amounts of acetylchoine to accumulate in the synaptic space
According to Dr stock's notes, Nerve fibers = Skeletal muscle fibers = Smooth muscle fibers = Astrocytes = Neurons = Erythrocytes =
Nerve fibers = -90 mV Skeletal muscle fibers = -85to 95 mV Smooth msucle fiers = -50 to -60 mV Astrocytes = -80 to -90 mV Neurons = -60 to -70 mV Erythrocytes = 8 to -12 mV
An example of a chemical ligand channel
Nicotinic aceltlycholine receptor channels
If a cell is placed in a ISOtonic solution,
No change occurs, concentrations are equivalent
Plasma (3l) is the ____ of blood
Noncellular portion
Abnormalities of extracellualr fluid Sodium Concentration is
Normal plasma Na = 140 - 145mmol/L
No ___ is required in glycolysis
O2 (anaerobic)
What is negative feedback?
Occurs when some function of the output of a system process or mechanism is fed back in a manner that tends to reduce the fluctuations in the output, whether caused by changes in the input or by other disturbances
Visceral adipose tissue
Omental (near pancreas) Mesenteric (around intestines) Epicardial (around heart)
Define the all or none principle
Once an action potential is initiated, it goes to completion
The blue lined image he gave us in class showed the Diffusion of a fluid molecule during
One thousandth of a second
The osmolal concentration of a solution is called osmolality when the concentration is expressed
Osmoles per kg of water
What compounds have extremely high solubility and almost function as though cell membranes do not exist?
Oxygen, nitrogen, carbon dioxide, alcohol
What is hematocrit?
Packed RBC volume
What two things make up the extracellular fluid and how many liters total are they?
Plasma and interstitial fluid 14 L
Because the ____ and ___ are separated, only be highly permeable capillary membranes, their ionic composition is ____
Plasma and interstitial fluid; similar (~2%)
Facilitated diffusion occurs in a fashion that is not linear, exhibiting a
Plateau effect at its V max
What is this an example of? Severe hemorrhage --> decrease in venous return --> decrease in cardiac output --> decrease in blood pressure --> decrease in coronary blood flow --> decrease in cardiac contractlity --> decrease in cardiac output
Positive feedback
What is the major element to know in the Intracellular fluid?
Potassium
Single frequency BIA relies on the ____ to calculate results
Prediction equations
What does the removal do?
Prevents continued muscle re excitation after the muscle fiber has recovered from its initial action potential
Define cell body (soma)
Processes the information contains a nucleus, command module
The most important difference is the greater concentration of ____ in the plasma
Protein
Define carrier protein
Proteins that bind with molecules or ions that are able to be transported and conformational changes in the protein molecules then move the substances through the interstices of the protein to the other side of the membrane
Resting metabolic rate
RMR Metabolic rate four hours after light meal with 30-60 minutes of resting quietly. Factors: ge sex body temp stress body surface area
Water moves
Rapidly across the cell membranes
What is net protein utilization ?
Ratio of amino acids converted to proteins
Define dendrite
Receives information
The ____ electrode is placed 5 cm from the yellow
Red
The hematocrit is the fraction of blood composed of
Red blood cells
What is the flowchart for negative feedback?
Reference point --> integrator/sensor --> effector --> controlled variable --> sensor --> integrator/sensor
Bioimpedance spectroscopy uses mathematical modeling to calculate the
Resistance at zero and infinite frequencies
In the creatine study talked about in class, 16 men and 16 women were involved in ___ volunteered for the study
Resistance training
Dr stock really emphasized that the opening and closing of channels in the heart are
SLOW so more can come in
Ca2+ is actively pumped back into the
SR
_____ is the propagation of action potentials along myelinated axons from one node of ranvier to the next node, increasing the conduction velocity of action potentials without needing to increases the diameter of the axon
Saltatory conduction
what is the order of the muscle cell, from outside to inside?
Sarcolemma, myfibril, myofilaments (actin and myosin)
What insulates the motor end plate?
Schwann Cells
Channel proteins and carrier proteins are usually _____ that are allowed to cross the membrane
Selective for the types of molecules or ions
In other words, the cell membranes are
Selectively permeable
When pressure rises too high, how do baroreceptors decrease blood pressure?
Send nerve impulses to the medulla of the brain that inhibits the vasomotor center which diminishes sympathetic activity causing diminished pumping by the heart and dilation of the peripheral blood vessels
In impedimed SFBF testing, sites should be
Shaved if needed and cleansed with alcohol (allow time to dry)
Hydrostatic pressure difference have only a _____ on fluid movement across a cell membrane
Small effect
What is the major element to know in the extracellular fluid?
Sodium
What is the SAID principle?
Specific adaptations to imposed demands
______ decreases membrane capacitance and ion flow 5,000 fold
Sphingomyelin
What is the stretch reflex?
Strike the pateller tendon with a hammer Muscle spindle stretch Type Ia afferent stimulates alpha motorneuon in L4 without interneruons (monosynpatic reflex arc) Antagonistic flexor relaxes via inhibitory interneorn alpha motor neuron stimulates quads to contract leg kicks
There are several types of adipose tissue
Subcutaneous visceral intramuscualr
Of the three fat types, ____ is not correlated with insulin sensitivity, but ____ are
Subcutaneous fat Subfascial adipose tissue and intermuscualr adipose tissue
The P groups ingested a ____ using the same protocol
Sucrose P
In Impedimed SFBF testing, the subject must lay
Supine; hands not touching the sides and feet/legs not touching
Perimysium
Surrounding each fasciculus or group of fibers
What does Ca calmodulin dependent protein kinase become when phosphorylated?
Synapsin proteins that anchor the acetylcoholine vesicles to the cytoskeleton
Where the T tubules originate from the cell membrane,
THey are open to the exterior of the muscle fiber, therefore they communicate with the extracellular fluid
What is energy?
The capacity to do work
As Na increases,
The cell depolarizes
As K increases
The cell repolarizes
If a cell is placed in a HYPERtonic solution,
The concentration of the solution will be higher, water will rush out of the cell, the cell will shrink
What is the difference?
The drugs are not destroyed by cholinesterase ; the action persits for many minutes to hours
The greater the motion
The higher the temperature
The indicator dilution principle is only valid if
The indicator disperses only in compartment measured The indictor disperses evenly in the compartment The indicator is not metabolized or excreted or correction must be made for excretion/metabolism
The most imporant means by which te body maintains a balance between water intake and output is by controlling the rates at which
The kidneys excrete urine
Impedimed SFBF testing must be conducted on
The left side of the body
The potential difference for K+ and Na+ are -94 mV and +61 mV, respectively. Wheat then causes the resting membrane potential to be -90 mV?
The membrane is far more permeable to K+
The osmole (Osm or osmol) is a non-SI unit of measurement that defines
The number of moles of solute that contribute to the osmotic pressure of a solution
What is end plate potential?
The opening of the acetylcholine gated channels to allow large numbers of sodium ions to pour inside the fiber, carries a large positive charge to create a local positive potential change
Epimysium
The outer layer
Between the components Plasma, Interstitial fluid (both make up the ECF) , and intracellular fluid,
The total osmolarity of each component is similar
Leucine threshold
Theoretical minimum dose of leucine required to stimulate an increase in muscle protein synthesis
Fluid intake is regulated by
Thirst mechanism, habits
Ordinarily, each impulse that arrives at the NMJ causes about ________ end plate potential as that required to stimulate the muscle fiber
Three times as much
The interstitial fluid (11L) bathes and surrounds the
Tissue cells
BIA was first used over 30 years ago to measure
Total body water
How does current flow deep in the muscle fibers to stimulate a contraction?
Transmission of action potentials along Transverse Tubules (T tubules) that penetrate all the way thorugh the muscle fiber one side to the other
Define secondary active transport
Transport is driven by the energy stored in the electrochemical gradient of another molecule (usually Na)
What do RBCs do?
Transport oxygen from the lungs to the tissues
Non lipid soluble molecules such as Na are able to make their way through the different cell membranes via
Transport proteins
Define antiporter
Transport substance in opposite direction of a driver ion like Na
Define symporters
Transport substance in the same direction as a driver ion like Na
Lactate concentrations are highest for
Type II muscle fibers
Afferent fibers
Type Ia and II
This stimulates sensory
Type Ia and II afferents
Afferent fibers
Type Ib
After an overnight fast, what was measured?
Urinary Cr Creatine concentrations Muscle Cr Concentrations body mass TBW ECW ICW
What are the causes of these prolonged contractions of the heart?
Usual voltage gated Na channels, which cause the spike Slower opening voltage gated Ca channels, which is largely responsible for the plateau Slower opening of K channels
While simple diffusion depends on the amount of substance present, facilitated diffusion reaches a max rate of diffusion called the
V max
Muscle Cr concentration was determined from the
Vastus lateralis muscle using a precutaneous needle biopsy technique
An example of a voltage gated channel
Voltage gated na+ channel
How would you set up an equation for: Volume of A = 1 mL Concentration of A = 10 mg/mL Concentration of fluid after dispersion = 0.01 mg/mL Volume of B?
Volume B = (1 mL x 10 mg/mL)/(0.01 mg/mL) Volume of B = 1000 mL
What is the general equation for measuring different fluid volumes?
Volume B = (Volume A x Concentration A)/(Concentration B)
You want to measure total body water in a patient. You inject 10 mL of a solution of antipyrine with a concentration of 150 mg/ml i.v. After equilibrium, the concentration of antipyrine in the blood is 0.03 mg/ml. what is the total body water of this patient, assuming no excretion?
Volume B = (Volume A x Concentration A)/(Concentration B) Volume B = (10 mL x 150 mg/ml)/(0.03 mg/mL) Volume B = 50 L
The maintenance of relatively constant ____ and stable composition of the ____ is essential for homeostasis
Volume; body fluids
Who coined the term homeostasis?
Walter cannon in 1929
Cell membranes are relatively impermeable to most solutes but are highly permeable to
Water
The lipid bilayer is a barrier to
Water and water soluble substances
When a current is passed through the body, the ___ primarily conduct the electrical current
Water containing fluids
The most reported side effect associated with creatine monohydrate supplementation has been
Weight gain due to increases in total body water
What is a controlled variable?
What is regualted
What causes the voltage gated calcium channels to open?
When an action potential spreads over the terminal, the channels open and allow calcium ions to diffuse from the synaptic space to the interior of the nerve terminal
Positive feedback
When there is a deviation of the controlled variable fro m the set point of the integrator may send a signal to move the controlled variable further away from a set point
Adding a hypertonic solution to the ECF
Would increase the osmolarity of the solution ( you are adding a solution with a larger concentration than the original starting point). the water will rush out of the cell due to a higher concentration on the outside than the inside, decreasing the ICF an increasing the ECF
The electrode bisecting the Ulnar Head is
Yellow
Electrodes must be hooked dup in order:
Yellow red, blue, black
How did Dr stock describe countertranpsort?
You have to go to Orlando but your friend has to go to tampa
Actin slides inward on myosin filaments pulling the
Z lines toward the center of the sarcomere
While channel proteins allow free movement, carrier proteins require
a binding of molecules or ions and result in a conformation change in the protein's structure
At no time during either exercise or rest does any single energy system provide
a complete supply
To counteract this,
a continually active Ca pump located in the walls of the SR pumps Ca ions away from myofibrils and back into the Sarcoplasmic Tubules
What is curare?
a drug that blocks the gating action of acetylchoine channels by competing for acetylchoine receptor sites
While neostigmine and physostigmine inactive acetylcholinesterase for a few ____ diisopropyl fluorophosphate inactivates it for ____
a few hours a few weeks
Secondary active transport was termed by dr stock as
a free ride
Every time the muscle fiber recovers , the depolarized area initiate a new action potential, aka
a muscle spasm
Diffusion occurs through the lipid bilayer or involves
a protein channel or carrier; simple diffusion by a channel, facilitated diffusion by a carrier
autogenic inhibition reflex
a sudden relaxation of muscle at very high muscle tensions to protect against muscle tear
These protein molecules penetrate all the way through the membrane, lying side by side in a circle to form
a tubular channel
In carbohydrate metabolism, what percentage is glucose?
about 80%
What is Westphal's sign?
absence or decrease in patellar reflex. could be caused by many things, including receptor damage peripheral nerve disease, lesion in motor cortex or pyramidal tracts, interruption of sensory and or motor impulse, transmission in femoral nerve
What happens to the choline?
absorbed actively into neural terminal to be reused for new acetylchoine
with these drugs, with each successive nerve impulse, additional acetylchooine
accumulates and simulates muscle fibers ; aka muscle spasm
Free fatty acids enter the mitochondria, are broken down, and form
acetyl-coA and hydrogen protons
Calcium concentration incraes, which increases the rate of fusion of
acetylcholine vesicles to the terminal membrane
After a few seconds, acetylcholine is split by ___ into acetate ion and choline
acetylcholinesterase
When there is a higher concentration of solute on one side of the cell membrane, water diffuses a
across the cell membrane toward the region of the higher solute concentration
Myosin head recocks and reattaches to
actin
Myosin head attaches to ____. This is known as ____
actin cross binding
I bands:
actin alone area between thick filaments in two adjacent sarcomeres bisected by a Z line
Intrafusal fibers do not contain
actin or myosin
Thin filaments are
actin, troponin, tropomyosin
What do the Ca ions do once releaed?
activate Ca calmodulin dependent protein kinase
When the membrane potential is changed from normal resting negative value to a positive value, there is an
activation of Na channels and a delayed activation of K channels
When a cell membrane moves molecules or ions uphill against a concentration gradient, the process is called
active transport
Almost all cells have the ability to reproduce
additional cells of their own kind
The movement to move against an energy gradient requires
additional sources of energy
In type one, there are more ____ enzymes for long term ATP production
aerobic
In shuffling pyruvate to the mitochondria, the rate of glycolsis is equal to the
aerobic metabolism of pyruvate produced from glycolysis
Pyruvate being shuttled into the mitochondria is known as
aerobic or slow glycolysis
When breakdown and subsequent depletion of PC does occur, an_____ is necessary to provide the energy to reform PC
aerobic recovery period
The oxidative system is an
aerobic system
Active transport occurs
against a concentration gradient and involves a protein carrier
In some muscles, two ____ of motor endplates may be found
aggregations (distal and proximal )
Cell membranes exhibit an
all or nothing principle that they are either open or closed at all times
The bioenergy currency in the cells of
all tissues
A motor unit is composed of either
all type one or all type 2 muscle fibers
innervation ratio can be determined by dividing the number of fibers in a muscle by the number of
alpha motor axons in the nerve supplying it
Extrafusal fibers are stimulated by
alpha motor neurons
Type Ia fibers stimulate ____ in spinal cord, causing contraction and shortening of entire muscle
alpha motor neurons
Afferent impulses to the spinal cord excite
alpha motor neurons, which results in contraction of muscle
A motor unit is defined as an
alpha motorneuron and all the muscle fibers that it innervates
According to dr stock, the rate occurs in response to the
amount of myelin encased
How long these gated channels stay open depends on the
amount of time necessary for process to take place
Secondary active transport uses
an indirect use of energy
Resistance exercise is very ____ but also is ____ which results in a net negative balance
anabolic Catabolic
EPOC is higher with anaerobic and intense exercise due to
anaerobic metabolism Temperature hormones
the conversion to lactate is known as
anerobic or fast glycolysis
Calorimeter:
artight chamber surrounded by water jacket; heat from person increases temp of water jacket, allowing calculation of energy temp
How much protein needed to boost the anabolic effect of exercise?
as little as 3 grams of EAAs (.5 leucine) or 4.2 grams of whey is enough to significantly increase protein synthesis
The cori cycle produces glucose from lactate even
at rest
In myelinated axons, action potentials physically occur
at the nodes
Motor axons conduct electrical impulses _____ from the neuron's cell body
away
Motor axons raise from conical protrusion -
axon hillock
BMR
basal metabolic rate; metabolic rate in supine position 12-18 hours after meal immediately after waking up in thermoneutral environment
The slowed inactivation of K channels results in voltages
below the resting membrane potential at the end of the action potential. This is known as afterhyperpolarization.
What are some methods of measuring protein quality?
biological value Net protein utilization Protein efficiency ratio Protein digestibility corrected amino acid score
The muscle fibers with one motor unit have identical
biomechanical and functional properties
Glucose is then used to maintain
blood sugar or for liver glycogen
In the absence of insulin the amount of glucose required cant get into the cells except for the
brain and liver
The proteins contract and cause the pits to
break away to the interior of the membrane, forming new vesicles
Extrafusal fibers make up
bulk of muscle
What is a fascicle?
bundle of muscle fibers surrounded by perimysium
Once activated, these dihydropyridine receptor channels trigger the opening of
calcium release channels in the cisternae and their attahced lontigudinal tubules
The absolute refractory period is a period of time after an action potential in which an additional action potential
cannot be generated no matter how larger the stimulus
There is an inverse relationship between the rate of ATP production and its
capacity
In Type one, there are more _____ for increased O2 delivery
capillary density
What are the factors that result in the switch from carbs and fat to all carbs?
carbohydrate metabolism produces more energy per liter of oxygen more fast twitch fibers are recruited, which are glycolytic hormonal changes: increase in epinephrine stimulates glycolytic enzymes Increased lactate from glycolysis inhibit triglyceride metabolism by reducing triglyceride availability
The oxidative system uses primarily
carbohydrates and fats as substances
Facilitated diffusion is also called____ because a substance transported in the manner relies ion a carrier to make it through the membrane
carrier mediated diffusion
It is important to note that simple diffusion does notrequire ____, while facilitated diffusion does
carrier proteins
How do the drugs work?
cause localized areas of depolarization of the muscle fiber membrane at the motor end plate where the acetylchoine receptors are located
What is myastenia gravis?
causes muscle weakness because of the inability of the NMJ to transmit enough signals from the nerve fibers to the muscle fibers
The basic unit of the body is the
cell
Calcium ATPase Primary active transport is resent on the ___ and the ____
cell membrane and Sacroplasmic reticulum in muscle fibers
Hypernatremia consequence is seen in
cell shrinkage
ATP energizes the synthesis of
cellular components
Mutiple oscilliations of leg is a sign of
cerebellar disease
Bioenergetics is the conversion of ____ into ______
chemical energy (food) to mechanical energy (muscle contraction)
This releases free fatty acids from fat cells into blood where they can
circulate and enter muscle fibers
What is an example of a contracile protein?
clathrin
The activation of muscles that work in concert with the agonist is known as
co activation / cocontraction
Within a few seconds, ____ appear in the terminal nerve membrnae caused by contractile proteins in the nerve ending
coated pits
The slight difference between the plasma and interstitial fluid mosm/L is due to
colloid osmotic pressure
ATP energizes glandular secretions against
concentration gradients
Therefore, the net rate of diffusion into the cell is proportional to the
concentration on the outside minus the concentration on the inside
Isotonic can be subdivided into
concentric and eccentric
The attachment of the Acetylcholine to the alpha subunit causes a
conformational change that opens the channel
Adipose fat tissue is a type of ___ that stores energy as fat
connective
Adipose tissue, being the morphological dimension, can be defined anatomically as the panniculus adiposus including
connective tissue and microscopic blood supply and nerves
What is a z line?
connects thin filaments from adjacent z lines, defines the end of the sarcomere
The peripheral control system involves
contracting the agonist and relaxing the antagonist muscles
Response:
contraction of agonist, relaxation of antagonist
The fact that we are alive is the result of complex
control systems
What catalyzes this reaction?
creatine kinase
As K leaves, it brings postivitity with it, thereby
creating electropositivity outside the cell and electronegativity inside the cell
A group of drugs known as _____ prevent the passage of impulses from the nerve ending into the muscle
curariform drugs
What are myofibrils?
cylindrical bundles of thick and thin filaments within the muscle fiber
Calcium ATPsae primary active transport maintains a low
cytocolic calcium concentration
Acetylcholine is synthesized in the
cytosol of the nerve fiber terminal and the transported through the membrane of the vesicle to the interior , where it is highly concentrated
What is an example of this? how does it work?
d tubocurarine Block action of acetylcholineon the muscle fiber acetylchoine receptors, prevent increase in permeability of the membrane channels to initiate action potential
Muscle spindles are important for preventing jerkiness of the body movements. This is known as
dampening
It has been observed that during glow/ moderate force contractions, even when muscle FORCE REMAINS CONSTANT, a slight ____ in firing rate may occur without recruitment of additional motor units
decrease
You run as fast as you can for 30 minutes and run consistently, without walking. You take your velocity at 15 - 20 s segments. Your velocity will
decrease over time
Aerobic processes
depend on oxygen
Patients with MS have a difficult time
describing symptoms
What is oxygen deficit?
difference between the amount of oxygen actually consumed during exercise and what would be consumed if energy demands met solely through aerobic metabolism (indirect measure of anaerobic energy)
Why are some protein sources better than others?
difference sources can vary widely in their amino acid profile, digestibility, nutritional value
Glucose does not easily ____ across cell membranes
diffuse
If you assume a membrane is only permable to K, and there is a high K concentration on the inside of the nerve fiber, the tendency will be for the K to
diffuse outside
The smaller unhydrated Na+ ion can then
diffuse through the ion channel
As the action potential reaches the T tubule the voltage change is sensed by ______ that are linked to _____ also called ____ in the adjacent sarcoplasmic reticular cisternae
dihydropyridine receptors Calcium release channels / ryanodine receptor channels
Primary active transport uses a
direct use of energy
What type of reflex arc are golgi tendon organs?
disynaptic
Anaerobic processes
do not require the presence of oxygen
The vesicles then ____ at the release sites, ____ with the neural membrane, and empty their acetycholine into the synaptic space by ___
dock fuse Exocytosis
At low frequency, current passes through the ECF spaces and ____ penetrate the cell membrane
does not
The entire glycogen content of some muslce cells can become depleted
during exercise
Which type of contraction can cause significant muscle soreness damage and edema?
eccentric
As Na+ enters, it brings positivity with it, thereby creating
electopositivity inside the cell and electonegativity outside the cell
Electromechanial delay is primarily due to the time it takes for the
electrical signal to continue into the muscle and mechanically activate the muscle machinery which in turn must transfer force externally
Secondary active transport co-transport involves the use of an
electrochemcial gradient usually for Na
ATP energizes active transport of
electrolytes and various nutrients across membranes
Increased metabolic rate is due to
elevated hormones, body temp, heart rate, and breathing rate
Eccentric movement involves
elongating
Acetylcholine from the vesicles is then
emptied through the neural membrane adjacent to the dense bars
Type I fibers are mainly for ____ while type II fibers are mainly for ____
endurance Strength and power
This is because the motor control scheme is optimized for
endurance capacity
The hydrolysis of ATP ____ the cross bridge cycle
energizes
Adenosine Triphosphate is the only compound that the body can use for
energy driven processes
The phosphagen system through creatine phosphate and the creatine kinase reaction, serves an an
energy reserve for rapidly replenishing ATP
At relative intensities of exercise above 60%, of max oxygen uptake, muscle glycogen becomes an increasingly important
energy substrate
What is the effective stimulus for causing acetylcholine release from the vesicles?
entry of calcium ions
In other words, the osm of the ECF is ____the osm of the ICF
equal to
Function is to ____ force among muscle fibers
equalize
The nernst equation is also called the
equilibrium potential
Food sources of protein: food protein is only considered complete if it contains all
essential amino acids
The relative constancy of the body fluids is remarkable because there is continuous
exchange of fluids and solutes with external environment as well as within different body compartments
These calcium ions then cause contraction. This is called
excitation contraction coupling
In all, stretch on muscle ___ muscle spindles; provides excitation muscle impulse and signal that results in ____ and ___
excites Contraction of muscle and inhibition of antagonist
What does Acetylcholine do?
excites the muscle fiber membrane;
What factors influence metabolic rate
exercise activity lean body mass age thyroid hormone growth hormone testerone sympathetic system fever cold climate
The onset of blood lactate accumulation :
exercise intensity at which blood lactic lactic concentration is greater than 4 mM
Changes in coactivation are thought to be an important adaptation associated with
exercise training or learning a new skill
The rupturing of these vesicles allowing acetylene into the synaptic space is called
exocytosis
In turn, a shift occurs in tropomyosin, causing
exposure of the binding site on actin to be exposed to myosin
All cells live in essentially the same environment- ______- for this reason it is called the internal environment or ____
extracellular fluid milieu interieur
The lipid bilayer is not miscible with the
extracellular fluid or intracellular fluid
Simulation can excite 3 to >100 _____ muscle fibers
extrafusal
Glucsoe is able to pass into the interior of cells via
facilitated diffusion and glucose carrier proteins
The ability to produce force rapidly may also be related to
fall prevention in older adults
Type IIa muscles (fast oxidative glycolytic) and type IIx (fast glycoltyic) are
fast twitch fibers
Where is fat?
fat is everywhere
Fat tissue is not just
fat/lipids
Lactate is highly correlated with ____, but not the cause of it
fatigue
Stimulation of the nerve fiber at rates greater than 100 times per second for several minutes often diminishes the number of actylcholine vesicles, so much that impulses fail to pass into the NMJ. This is referred to as
fatigue of the NMJ
Type one muscle fibers are more
fatigue resistant
Oxidative (also called the areobic system): formation of ATP from the breakdown of
fatty acids using oxygen in mitochondria
A control system that responds in anticipation of a change
feed forward
Muscle spindle density varies according to function: larger muscles with course movements have ____, smaller muscles with fine movements have ____
fewer Many
Smaller muscles (first dorsal interosseous) rely more on
firing rate
Motor units can also vary their force output by changing their
firing rates
At any specified force level, there is an inverse relationship between
firing rates and recruitment threshold of motor units
Low threshold motor units are recruited ___ and have lower force capabilities than higher threshold motor units
first
The fetal acetycholine receptor complex is composed of ____ subunit proteins:
five Two alpha one beta one delta one gamma
In the diagram he showed in class, the channel protein had a _____ to get the ion across while the carrier protein _____
flap that moved Flipped over
The generation of action potential within one motor unti results in a
force twitch
Define anabolism:
formation of large molecule from small protein/ fat/ carbohydrate substrates requiring energy
Channel proteins allow ____ of water or ions along their concentration gradient
free movement
Anytime muscular effort (force torque power) is measured, it is important to remember that what is being observed is the net sum
from all of them muscle that surrounds a joint
At a certain point, the membrane's diffusion potential is reached, stopping further Na
from entering the cell. Note that a concentration gradient may still remain
Each cell is specifically adapted to perform a limited number of
functions
At a certain point the membrane diffusion potential is reached stopping
further K from leaving the cell. Note: concentration gradient may still remain
What are cross bridges ?
globulular region of myosin that projects toward thin filament
Immediately upon entering cells, glucose combines with _____ (liver) or hexokinase (other cells) to form _____
glucokinase glucose 6 phosphate
In Carbohydrate metabolism, the final products of carbohydrate digestion in the alimentary tract are almost all entirely
glucose Fructose Galactose
Fructose and galactose are converted to
glucose in liver
When you run a marathon what limits you?
glycogen
Muscles and liver contain
glycogen storage granules in the cytoplasm
Increases in IM glycogen affects ____ production of ATP
glycolytic and aerobic production
Each segment of the spinal cord has several million neurons in its
gray matter
The disparity is largely caused by
greater leakage of K+ through the channels
The rate at which molecules can be transported by facilitated diffusion can never be
greater than the rate at which the carrier protein molecule can undergo change back and forth between the two states
On the legs, the yellow electrode is placed 5 cm below the
greater trochanter (anterior portion of the thigh)
What are the points of the subnerual cleft?
greatly increase the surface area at which the synaptic transmitter can act
This can create a trade off of
health related issues
This is common is ___, where the plateau lasts for as long as ___ and cause prolonged contraction of the ____
heart muscle fibers 0.2-0.3 seconds Heart
The motion of particles is called
heat
Calories
heat required to raise the temp of one gram of water by one degree C
Disease that affects the kidney's ability to excrete waste may lead to
high blood pressure
All else being equal, substances will diffuse from an area of
high concentration to low concentration
Low threshold motor units have
high firing rates
Blood lactate accumulation is greatest following
high intensity intermittent exercise (e.g. resistance training)
However, golgi tendon organs signal muscle force thoruh the entire physiological range, not only at
high levels of tension
The motor units you turn on first tend to have
higher firing rates than the later recruited high threshold motor units
Interneurons are small and
highly excitable
Control systems are implemented to maintain
homeostasis
Triglycerides stored in fat cells can be broken down by
hormone sensitive lipase
The amount of PFK you have determines
how well your system works; high exercise will increase pfk and glycolytic activity will occur more readily
Hypernatremia may occur in patients with
hypothalamic leions or infants
Multiple sclerosis is an
immune mediated inflammatory demyelinating disease of the CNS
Some changes in enzymes will have more ___ than others will
impact
Excess postoxygen consumption:
improved description of oxygen dept as representing the energy borrowed from anaerobic metabolism to perform exercise
Where is actylcholine synthesize?
in the cytoplasm
Where are synaptic vesicles located?
in the terminals of a single endplate
Light activity postexercsie clears lactate more so than
inactivity
Food protein that lack one or more of the essential amount acid are termed _____ and not capable of causing growth, but instead can lead to protein malnutrition if eaten in isolation
incomplete
Eventually the resolution of the neurological deficits is ___ or their occurrence is ___ and the diagnostic dilemma begins
incomplete Too frequent
Overall, there is an ____ in the amount and availability of glycogen to be stored in response to exercise
increase
Thus, an increase in motor unit recruitment is not always necessary to
increase force
After exercise, recovery of muscle protein synthesis requires dietary protein of BCAAs to
increase tissue levels of leucine in order
ATP and PC are more likely to be ______ from hydrolysis of ATP and subsequent production of H+ as well as accumulation of _____ (also formed by hydrolysis of ATP)
increased acidity Pi
Higher pressure results in
increased energy available to cause net movement from high pressure to low pressure
As exercise intensity increases, the percent of atp from carbs
increases
Conversely, as muscle velocity decreases during slower movements, more cross bridges have time to attach and generate force, thus force
increases
Weight and sprint activities: studies have shown
increases and no change in glycogen
Muscle spindle reflexes oppose (correct for)
increases in muscle length (stretch)
In order to produce high forces ,the central nervous system
increases the recruitment of motor units and their firing rates
Changes in glycolytic enzymes may improve performance by
increasing ATP availability from glycolysis
The volume of a fluid in the body can be measured by placing an ______ in the compartment, allowing it to ____ evenly throughout the compartments fluid, and then ____ the extent to which the substance becomes diluted
indicator disperse analyzing
Define constant amplitude
info is coded by frequency, not amplitude
At the same time, synergistic muscles are activated, while antagonistic muscles are
inhibited
The normal resting state concentration of C ions is too little to elicit contraction. Therefore, troponin tropomyosin complex keeps the actin filaments ___ and maintains a relaxed state
inhibited
what does end plate potential do ?
initiates an action potential that spreads along the muscle membrane and causes a muscle contraction
Assuming that a membrane is only permeable to Na+, because of the high Na+ concentration outside the nerve fiber, there is a tendency for it to diffuse
inside
The rate of glucose transport is increased via
insulin
Together, ______ allow skeletal muscle to coordinate protein synthesis with physiological state and dietary intake
insulin and leucine
During exercise, the rate of glycogen depletion is related to
intensity
The leucine content of protein and how fast it can be digested will determine the
intensity of muscle protein synthesis
The extent to which each of the three energy systems contributes to ATP production depends on the
intensity of muscular activity and secondarily on the duration
Most of the signals from the brain terminate on
interneurons
Interstitial fluid is found in the ____ - the spaces between the cells also known as ____
interstices Tissue spaces
Plasma constantly exchanges substances with the
interstitial fluid
Function of gamma motoneruons: innervate
intrafusal fibers
Muscle spidles consist of _____ muscle fibers in parallel with ____
intrafusal muscle fiber extrafusal muscle fibers
Some free fatty acids come from
intramuscualr sources
During the slow phase, there is aerobic metabolism of
intramuscular and blood lactate
In the idea of muscle quality, studies show that when referencing the size of a muscle, you have to account for
intramuscular fat
Glycogen phosphorylase is an enzyme that contributes to the breakdown of
intramuscular glycogen to glucose
The signals from these two receptors are almost entirely for the purpose of
intrinsic muscle control.
In general there is an _____ relationship between a given energy system's max rate of ATP production and the total amount of ATP it is capable of producing over a long period of time
inverse
At any specified force level, there is an _____ between the firing rates and recruitment threshold of motor unit
inverse relationship (negative)
Muscle contraction under active tension can either be
isometric or isotonic
The action potential spreads along the entire membrane until until
it has been completely stimulated
The amount of force or tension that a muscle can produce at any given movement is intimately related to
its length
The amount of force that can be generated during a muscle contraction is closely related to
its velocity
Muscle spindle are removed, there is
jerkiness of muscle contraction
Significant amounts of tension in isometric contraction may be developed in muscle to maintain
joint angle in relatively static or stable position
Measured in _____ also known as calories
kilocalories
With increased exercise, pyruvate is converted to
lactate
Lactate shuttle hypothesis:
lactate may also be used by tissues including skeletal muscle to synthesize glycogen or pyruveate (which would enter aerobic metabolism)
blood lactate concentrations reflect both
lactate production and clearance
The sarcoplasmic reticlum is composed of two major parts
large chambers called terminal cisternae that abut the T tubules Long longitudinal tubules that surround all surfaces of the actual contracting myofibrils
Alpha motor neurons innervate
larger skeletal muscle fibers
These drugs can cause death if the spasm occurs in the
laryngeal area
Subcutaneous adipose tissue:
layer under the skin
Muscle spindles sense muscle
length and rate of change in length
Alpha motor neurons and gamma motor neurons are co activated so that muscle spindles can be sensitive to change in
length during contraction
Eccentric contractions involve the muscle _____under active tension
lengthening
Out of the three BCAAS, ____ is probably the most imperative
leucine
Untrained people need more for ____ than trained people
leucine threshold
Research suggests that out of the EAAs the branched chain amino acids are the most important. These include:
leucine, isoleucine, and valine
The sudden insurgence of sodium ions into the muscle fiber when the aceylcholine gated channels open causes the electrical potential inside the fiber at the ____ to increase in the positive direction
local area of the endplate
The opening of Na channels generates ____ that depolarizes adjacent portions of the membrane, thus opening ____ Na channels
local current more
This creates a
local potential called the end plate potential
In high intensity training, you need
longer rest periods, as shorter rest periods lead to worse performance
Since it takes time for cross bridge attachment, when filaments slide past one another during rapid movements, force is ____ due to the lower number of cross bridge that have become attached
low
At time, there is a need to keep a high concentration one side of the cell membrane despite a
low concentration the other side
We have ____ of lactate in our system constantly
low levels
Motor units are recruited in an orderly fashion
low threshold / type I muscle fibers before high threshold Type II muscle fibers
Larger motor units produce
lower firing rates
To get to the high threshold motor units, the body must first recruit
lower threshold motor units
Thus, the original stretch is opposed and muscle length is
maintained
A skewed daily protein distribution fails to max potential for muscle growth or
maintenance
In disease, compensatory mechanisms may allow
maintenance of homeostasis
In order to combat this we have systems to
make ATP
Larger, gross movements require
many muscle fibers per motor unit. Example: gastrocnemius - 1934 fibers / motor unit
For many small muscles, motor units are fully recruited far before
max force has been reached
In many movements the rate of force development is more important than the
max force that can be produced
What is biological value?
measures the amount of nitrogen retained in comparison to the amount of nitrogen consumed
What is direct calorimetry
measuring heat production to determine metabolic rate
In summary, an ion concentration difference across a permeable membrane can create a
membrane potential
A very small number of ions must be transferred inside or outside of the cell for a
membrane potential to exist
Muscle fibers differ in respect to
metabolic and contractile capabilities
Intramuscular fat is involved with
metabolic disease
In many muscles, most of the NMJ are located near the
middle of the muscle
Examples of complete food proteins
milk eggs meat poultry fish
Lowintensity activies that can be sustined for
minutes, hours, days
What supplies the ATP used for synthesis of Acetylchoine?
mitochondria
with decreased exercise, pyruvate is stored in the ____ via the krebs cycle and converted to ATP later
mitochondria
Number of synapses:
monosynaptic reflex arc (1 synapse)
As Americans, we need to eat
more for breakfast and less for dinner
Mechanism may be related to actin - myosin becoming
more sensitive to calcium released form the sarcoplamic reticulum during subsequent muscle contractions
In different cell types, AP will be different due to
morphology
Isometric prevents
motion
The properties of a muscle fiber are dictated by the
motorneuron that is innervated by
Isometric contraction may be used to prevent body segment from being
moved by external forces
IN other words, the AP propagates before
movement occurs
Define active transport
movement of ions or other substances across the membrane in combination with a carrier protein in such a way that the carrier protein causes the substance to move against an energy gradient
All molecules and ions in the body are in constant motion, with each particle
moving in a separate way
When the A band takes over, coloration gets
much darker
Intrafusal fibers run in parallel with extrafusal fibers, but they are
much shorter
Propriospinal fibers provide pathways for
multi segmented reflexes
ATP energizes
muscle contraction
Extrafusal fibers provide force for
muscle contraction
This production of H+ ions adds to
muscle fatigue
Repeated max stimulation of protein synthesis will increase / maintain
muscle mass
Gamma motor neurons constitute the middle of the
muscle spindle
Simulation at 8 Hz causes smooth contraction, illustrating smoothing effect of
muscle spindle system
A sudden stretch of the muscle excites
muscle spindles
Intrafusal fibers are encapsulated in sheaths to form
muscle spindles
Simulation of gamma motor neurons stimulates ____ in muscle spindles, a special type of sensory receptor
muscle spindles
Stimulus:
muscle stretch
Sudden relaxation of muscle may protect against
muscle tears
This is explained by the fact that at a sarcomere's resting length the max number of cross bridges are able to bind with the thin filaments, thereby producing
muscle tension
This perpetuates
muscular contraction
Axons may be covered with white substance high in lipid (fat) content called the
myelin sheath
In type one, there is more ____ (oxygen binding protein)
myoglobin
What are thick filaments?
myosin
Titin is important because it anchors
myosin, the myosin is in the middle, attached to actin
Positive feedback is often associated with
negative events or a viscous cycle, but it CAN be positive
Most control systems operate via
negative feedback
Recovery due to ____ can happen when 1 L of blood is lost. Death is caused by ____ when 2 liters of blood are removed
negative feedback positive feedback
ATP energizes
nerve conduction
It could be argued that the notion of muscle fiber type is really a
nervous system derived phenomenon, hence the term neuromuscular
High intensity exercise in absence of nutrition will result in
net breakdown
Interneurons comprise ____ for most reflexes
neural circuitry
Individual muscle fibers never behave independently. They are controlled by the
neuron which innervates them
In order for the continued function of this process
new vesicles need to be reformed rapidly
In diffusion...
no additional energy is required
Sheath is interrupted every 1-3 mm by a
node of ranvier
The plateau phase limits the
number of heart beats we can have
Visceral adipose tissue (VAT) is incrased in
obesity
Untrained lactic acid threshold:
occurs at 50-60% of max oxygen consumption
This process takes even longer in
older adults
How many seats are on the bus during facilitated diffusion?
one
Normal blood lactate levels return within
one hour postexercsie
Hydrogen ATPase primary active transport concentrates H ions up to
one million fold
Under normal circumstances, it is not possible to activate
one muscle
It is called osmolarity when it is expressed as
osmoles per liter of solution
The Na+K+ pump plays a critical role in regulating
osmotic balance
A bands:
overlapping of myosin and actin
The slow phase restores muscle and blood
oxygen stores
What is oxygen debt?
oxygen taken in above resting values after exercise
Patients with MS may present with ____ of a hand that resolves, followed in a couple months with ____ in a leg or ____
paresthesia Weakness visual disturbances
Hydrogen ATpase primary active transport is found in
parietal cells of gastric gland (HCl secretion) and intercalated cells o renal tubules (controls blood pH)
Active recovery promotes glycogen levels more than
passive recovery
Thick and Thin filaments slide
past each other
Lipid soluble substances can
penetrate the lipid bilayer
T tubules branch among themselves and form entire ___ of T tubules interlacing among all separate myofibrils
planes
Examples of incomplete proteins inlude
plant proteins corn lentils beans nuts soy is one of the few examples of a plant protein that is considered complete
Water soluble molecules cross cell membranes via channels or other transport proteins. Water is transported via
pores called aquaporins
Not all forms of feedback are negative; sometimes they are
positive
Action potentials are a classic example of
positive feedback
These sensory roots are also known as
posterior or dorsal roots
Intracellular fluid is made of
potassium magnesium phosphate
This is thought to be due to a condition known as ____, in which greater force becomes available from each twitch
potentiation
These examples are summed up in one comparison:
power vs precision. Power being gross movements, precision being fine motor control
VAT is more ____ and higher in ____
pro inflammatory higher in men
The major difference in plasma vs interstitial fluid is
protein
In rehab without nutrition, there is a shift toward
protein breakdown
In rehab with nutrition, there is a shit of
protein synthesis
Swinging of cross bridges, thin filaments and Z lies are
pulled toward the center of the sarcomere
The muscle fiber is a ____ to the neuron
puppet
Without the special neuronal circuits of the spinal cord, even the most complex motor control systems in the brain could not cause any
purposeful human movement
The end result of glycollysis is
pyruvate
Lactate dehydrogense (LHD) is an enzyme that converts
pyruvate to lactate
what does diffusion mean?
random molecular movement of substances molecule by molecule either through inter molecular spaces in the membrane or in combination with a carrier protein
Measurable fatigue occurs
rarely
Phosphofructokinase (PFK) is the
rate limiting step of glycolysis
When measuring membrane potential, it is important to note that we are
recording the difference in voltage between the extracellualr and intracellualr membrane
After exercise, heart rate and breathing are still elevated to enable
recovery
They are all ____ at the same time
recruited or derecruited
Larger muscles of mixed fiber types relay more on ___ and may have lower firing rates
recruitment
Leucine is important becuase it helps with
regeneration of muscle tissue
Response
relaxation of agonist , contraction of antagonist
Within the vesicular tubules in the SR is an excess of calcium ions, high in concentration, many of which are
released from each vesicle when an action potential occurs in an adjacent t tubule
In an isometric contraction, active tension is developed within muscle but joint angles
remain constant
During this period of time, K channels
remain open
From cell to cell, the concentrations of various intracellular constituents are
remarkably simliar
In some instances, the excited membrane does not
repolairze immediately after depolarization
When wanting to improve body mass
resistance exercise is better than aerobic activity
What may the patient die of in this disease?
respiratory failure
Gamma motor neurons adjust sensitivity of muscle spindle, so it will
respond appropriately during muscle contraction
The oxidative system is the primary source of ATP at
rest and during low intensity activities
Na channels go from
resting --> open --> inactive --> resting
The optimal length at which a sarcomere can produce force is near its
resting length
During the rapid phase, the majority of intramuscualr PC is
resynthesized
The binding of ATP breaks the linkage so lack of ATP produces
rigor mortis
This high volume is referred to as a
safety factor
Actin filaments attached to each end of the
sarcomere
The sliding filament theory is the shortening of
sarcomeres
Glycolysis occurs in the
sarcoplasm
Ca2+ is stored in the
sarcoplasmic reticulum
Muscle fibers from one motor unit are ___ throughout the muscle and are consequentially in proximity with other muscle fibers from other motor units
scattered
_____ surround the nerve axon forming a myelin sheath
schwann cells
Energy is stored in the chemical bond between the
second and third phosphate groups
What is an example of feed forward?
secretion of digestive enzymes by the pancreas during chewing Eating too much --> gain weight --> sad --> eat more --> gain more weight
When we are hungry we when we are cold we When we are afraid we
seek food seek warmth fight or flight
The use of appropriate exercise intensities and rest intervals allow for the
selection of specific energy systems during training and results in more efficient and productive regimens for specific athletic events with various metabolic demands
For example, there is no neuronal circuit anywhere in the brain that causes specific two and fro movements of the legs during walking. Instead the brain simply
sends commands to the spinal cord and reflex circuits control the details of the movement
Define axon
sends information out to other neurons or target cells (muscle fibers)
Sensory fibers enter the spinal cord almost entirely through the
sensory roots
Multiple Frequency BIA involves taking impedance measurement at less than
seven frequencies
How long is the slow phase?
several hours
Thick and then filaments DO NOT
shorten
Concentric movement involves
shortening
Concentric contractions involve muscle developing active tension as it
shortens
Moore Et al demonstrated that 40 g v 20 g of egg protein post exercise resulted in
similar muscle protein synthesis
Diffusion through the cell membrane can occur by
simple diffusion and facilitated diffusion
Each muscle has a different average motor unit ____. referred to as the innervation ratio
size
Motor units that contain type I slow twitch and type II fast twitch fibers are organized based on
size factor
This recruitment order of muscle fibers is according to the
size principle
Lactate is produced by
skeletal muscles and other tissues
Type I (sow oxidative) muscles are
slow twitch
Whole body exercise may require more protein EAAs to simulate muscle protein synthesis as opposed to
small muscle mass exercise
Intrafusal fibers are ____ than extrafusal fibers
smaller
Both Na+ and K+ are ____ when dehydrated
smaller (Na+ 3.58 A ---> .95 A; K+ 3.31 A --> 1.33 A)
As lactate threshold increases
so does endurance performance
This absolute refractory period is due to the inactivation of
sodium channels
Recalling information from previous lectures, a sudden increase in the membrane potential is sufficient to initiate more and more
sodium channels to open, leading to an action potential
Extracellular fluid is made of predominantly
sodium, chloride, bicarbonate, oxygen, glucose, carbon dioxide
Protein is not a significant
source of energy
Stretching muscle (increasing length) also stretches the
spindle
lysis means
split or break down
Relaxation occurs when the stimulation of the motor nerve
stops
glycolysis is the breakdown of carbohydrates, either
stored in the muscle or glucose delivered in the blood to resynthesize ATP
Your goals determine your
strategy
Athletes with higher creatine phosphate levels are well suited for
strength / power sports
This reflex opposes further
stretch of the muscle
They operate almost completely at a
subconsious level
What are the smaller folds of the membrane at the bottom of the gutter called?
subneural clefs
Glyco means
sugar
In converting pyruvate to lactate, The rate of glycolysis _____ aerobic metabolism of pyruvate produced from glycolysis
supersedes
Endomysium
surrounding individual fibers
ATP storeage is not
sustainable
The functional significance of this is that the neuromuscular system is better suited for
sustaining force than producing large amounts of max force
What type of sporting event would glycolsis take place?
swimming, longer springs,
Secondary active transport co transport uses protein cotransporters, classified as
symporters or antiporters
This fatigue of the NMJ is the same effect that causes fatigue of the
synapses in the CNS when the synapses are over excited
What is the invaginated membrane of the muscle fiber called?
synaptic gutter/ trough
What is the space between the muscle fiber and the terminal called?
synaptic space / synaptic cleft
What is acetylcholine absorbed into?
synaptic vesicles
Insulin and leucine are considered
synergists
Lactate is then transported to the liver and used to
synthesize glucose
myosin filaments are oriented with their
tails toward the center of the sarcomere
Golgi tendon organs are lcoated in the
tendon
Golgi tendon organs sense
tendon tension and rate of change in the tension
Low threshold mechanoreceptors are located in ____ that detect tension development in the muscle
tendons
During the activated state, Na ions can pour inward through the channel, increasing
the Na permeability of the membrane as much as 500-500 fold
The rate of diffusion is determined by
the amount of substance available, the velocity of kinetic motion, the number and sizes of openings in the membrane through which the molecules or ions can move
The cell body of each neuron is located within
the anterior (ventral) horn of the spinal cord
Glyclosis (also called the lactic acid system) is the ______ either stored in the muscle or glucose delivered in the blood to ____
the breakdown of carbohydrates resynthesize atp
The t tubules are actually internal extensions of
the cell membrane
Important observation: muscle fibers do not span
the entire length of the muscle
In the adult, what substitutes for the gamma protein?
the epsilon protein
What is a sarcomere?
the functional unit of a muscle fiber; contains all protein and biomachinery needed for a muscle to conract
Nerve signals are transmitted by action potentials which are rapid changes in the membrane potential that spread along
the nerve fiber membrane
Each action potential begins with a sudden change from
the normal resting potential to a positive potential and ends with an almost equally rapid change to the negative potential
This phenomenon was terms ____
the onion skin
The human body has thousands of control systems that exist within ___ and also ____
the organs; to control the interrelations among organs
If a cell starts to swell for any reason
the pump becomes activated
The rate of diffusion of water is called
the rate of osmosis
Dr stock used the image of a pool of muscle fibers.
the small circle in the picture represented the number of motor units needed for walking, while the larger circle represented the number of motor units needed to do a squat
The science of human physiology attempts to explain
the specific characteristics and mechanisms of the human being that make it a living being
Therefore, when the action potential spreads over a muscle fier membrane, a potential change also spreads along
the t tubules to the deep interior of the muscle fiber, eliciting a contraction
Electromechanical delay is the idea that if you measure electrical activity of a muscle and force output, max / submax delay is
the time to start vs when the force starts
Adaptations will depend on
the type of exercise and influenced by factors like muscle hypertrophy
The nernst potential (equilibrium potential) is the
theoretical intracellular electrical potential that would be equal in magnitude but opposite in direction to the concentration force
Leucine saturation
theoretical minimal single oral dose of leucine required to maximally statute muscle protein synthesis
How many seats are on the bus in simple diffusion ?
there are unlimited seats on the bus
Protein channels are distinguished by two important characteristics:
they are often selectively permeable to certain substances many of the channels can be opened or closed by gates that are regulated by electrical signals (voltage gated channels) or chemicals that bind to the channel proteins (ligand gated channels)
Patients frequently do not bring these complaints do their dr because
they resolve
Contraction phase is step ___ out of four in sliding filament theory
three
Muscle spindles are distributed
throughout muscles
The physiological basis for his relationship is that the force generated by a muscle is directly related to the
total number of cross bridges attached
T tubules run
transverse to myofibrils
Myelin helps to insulate the nerve impulse conduction as it
travels down the axon
Ca2+ binds to ____
troponin, a protein on actin filament
when you are sedentary, you cannot
turn on all muscle fibers. This can be alleviated by strength training
this also results in motor units ____ at higher force level than that at which they were recruited
turning off (derecruitment)
Formed by branches of
type IIb afferents
The deeper you get into the muscle, the more
type one fibers you see (slow)
What was the difference between the Type II fiber type in a 48 vs 88 yr old?
type two muscle fiber diameter decreased in the 88 year old
Actin and myosin return to their
unbound state
The action potential moves along the nerve fiber
until it reaches the end
What is a channel protein?
uses watery spaces all the way through the molecule and allow free movement of water, as well as selected ions and molecules.
Indirect calorimetry
using oxygen utilized Co2 produced and their ratio at calculate metabolic rate ; also provides insight into amount of carbs vs fat being burned
Explain how childbirth is an example of positive feedback
uterine contractions strong enough for baby head to push through cervix --> stretching the cervix sends signals to uterus muscle --> Stronger contraction
Myelination increases
velocity and conserves energy
EAA + exercise =
very anabolic
Type IIa and IIx fibers are
very fatigable
Smaller, more precise movements require
very low muscle fibers per motor unit Example: rectus lateralis (eye) = 5 fibers / motor unit
These channels typically open and close
very rapidly; fractions of a ms
Gated channels exist as
voltage and chemical
Action potentials are largely a function of the behavior of
voltage gated Na and K channels
What is located at each side of the dense bars?
voltage gated calcium channels
Additional transport molecules have to
wait until everything returns to normal
BIA is based on the fact that body contains
water and conducting electrolytes
What is the relationship between glycogen and water?
water follows glycogen at a 1-3/4 gram ratio
Thus, lactate is viewed not as a waste product but as a
way to shuttle glucose around the body
Enzymes increase due to
weight, spring, endurance training
In simpler terms, potentiaion is
when the individual produces more force voluntarily than showed to be produced by motor units at any point in time
However, the muscle fibers within a single motor unit are not located
within a single cluster
Where are baroreceptors located?
within bifurcation region of the carotid arteries in the neck as well as the arch of the aorta in the thorax
Adding isotonic solution to the ECF
would increase the ECF, but not the ICF
IF you dont recruit it
you cant adapt it
