UCI E112L

Expected result: muscle length vs. delta P

Delta P increases with length, then levels off at maximum force, then decreases again - When length of muscle is either too short or too long to begin with, the muscle doesn't get enough strength to create any force

Expected result: stimulus amplitude vs. delta P

Delta P rises exponentially with stimulus amplitude, but then levels off at the maximum delta P (maximum tension)

Expected result: frequency vs. delta P

Delta P starts out stable with frequency, but then rises with stimulus frequency exponentially until stabilizing again at maximum delta P

Trace the pathway of oxygenated and deoxygenated blood in the heart.

Deoxygenated blood: in though superior and inferior vena cavas, right atrium, tricuspid AV valve to right ventricle, pulmonary semilunar valve to pulmonary trunk/arteries to lungs (pumonary) Oxygenated blood: in through pulmonary veins, left atrium, mitral/bicuspid AV valve to left ventricle, aortic semilunar valve to aorta to body (systemic)

What is the EMG amplitude directly proportional to?

Directly proportional to the number of active muscle fibers!! *It's also proportional to motor unit number and force being generated, but not linearly.

What is the EMG amplitude directly proportional to?

Directly proportional to the number of active muscle fibers!! (also non-linearly proportional to motor unit number and generated force)

Human gastrocnemius function

Dorsoflection

Type 3 Lever

Force in/effort is in the middle. - Have mechanical disadvantage = b/c the effort is closer to the fulcrum than the load, the effort must always be greater than the load - Closer the effort is to the fulcrum, the farther the load moves. Farther the effort, the higher the load lifts. - Exp: tweezers or crane, biceps lifting something in hand *FRE123*

Type 1 Lever

Fulcrum is in the middle. - The further Fi is from the fulcrum, the less effort is needed. - Exp: scissors or pliers, head moving up and down *FRE123*

Type 1 Lever

Fulcrum is in the middle. - The further Fi is from the fulcrum, the less effort is needed. -seesaw -head moving up and down

Where does gas exchange occur?

In the respiratory zones (alveoli is like sponge = lots of surface area for gas diffusion)

What factors affect VO2 max?

Increasing sympathetic activity increases both factors affecting VO2 max 1. Cardiac output --> stroke volume --> preload or afterload - Increase preload or decrease afterload increases stroke volume, CO, and VO2 max 2. a-vO2 difference --> capillaries and mitochondria and muscle blood flow - Higher flow and more capillaries/mito increases a-vO2 difference and ergo VO2 max

MAP (mean arterial pressure) vs. pulse pressure

MAP = P(diastolic) + 1/3 P(pulse) = Q * TPR - Because diastole lasts longer than systole, the mean isn't simply an average Pulse pressure = P(systolic) - P(diastolic)

Conduction

Molecules collide = heat transfer when two objects touch. - Rate depends on: area (more area more transfer), temp diff (more diff more transfer, thermal conductivity (high k faster temp change) - Before conduction, objects vibrate at different levels. After, they vibrate at same level. - Exp: standing on a rug vs. standing on tile

Eccentric muscle contraction

Muscle lengthens when contracting Force of Muscle < Load - Muscle contracts to some extent, but the load is to heavy so muscle stretches instead of contracts

Eccentric muscle contraction

Muscle lengthens when contracting (Force of Muscle < Load). Muscle contracts to some extent until load too heavy that muscle stretches instead

Isometric contraction

Muscle maintains length when contracting (i.e. there's no net movement of bones/muscles) Force of Muscle = Force of Load;

Isometric contraction

Muscle maintains length when contracting (i.e. there's no net movement of bones/muscles) - Force of Muscle = Force of Load

What is the FEV1.0/FEV ratio? How do obstructive/restrictive lung diseases affect this ratio?

Ratio = how fast the patient *exhales* - Obstructive = ratio is reduced - Restrictive = ratio is normal

Isotonic contraction aka concentric

Shortens length when contracting Force of Muscle > Force of Load - Muscle contracts/shortens as it lifts

Single twitch vs. complete tetanus: latent period, rise time, duration, t5, delta P

Tetanus has a higher rise time, duration, relaxation time, and delta P. The only thing unaffected by tetanus is latent period.

Korotkoff sounds

The blood spurt sound you heart when the cuff is puffed up enough that the arterial pressure is equal to or less than systolic pressure so blood squirts past the cuff = partial blockage - Heard as long as P(sys) > P(artery) > P(dia)

Why might feathers/fur prevent heat loss?

They trap a layer of still (non-convecting) air against the skin = insulating air barrier between skin and environment so organism doesn't lose heat directly off the skin due to conduction/convection.

What does the ratio of neurons to muscle fibers indicates about the muscle?

The smaller the neuron to fiber ratio, the more precise control of the muscle's actions are needed - Exp: eye muscles are 1:1, finger muscles are 1:10, back muscles are 1:100, and gastrocnemius is 1:2000.

What is the primary regulator of ventilation?

arterial partial pressure of carbon dioxide - oxygen levels only regulate when they are *very low*

a-vO2 difference

arterial-venule oxygen difference = amount of oxygen (mL) released from each mL of blood = difference in oxygen carried in veins to that in the arteries

EKG: PQRST

1. P wave = atrial depolarization (small bump in beginning) 2. QRS complex = ventricular depolarization (slight down, big spike up, stright down) 3. T wave = ventricular repolarization (small bump at end)

What 3 factors control the VELOCITY of an isotonic contraction? Which factor did we test in lab 4, expt 3?

1. Relative load - Larger load has slower velocity 2. Number of fibers contracting - More active fibers = lower overall load/fiber = higher velocity 3. Fiber Type - Slow vs. fast twitch muscles

What 3 factors control the VELOCITY of an isotonic contraction? Which factor did we test in lab 4, expt 3?

1. Relative load (large load = slower) 2. # of contracting fiber (more fibers = faster) 3. Fiber type (slow vs. fast twitch)

Exercise detraining

1. SV max lower so plasma volume down 2. a-vO2 max lower = less mitochondria so less oxidative capacity in muscle

TV, FVC, f, RV

1. TV = tidal volume = volume of air expired during normal breathing (normal peak to trough) 2. FVC = forced vital capacity = max volume that can be exhaled (max peak to min/max exhale) = ERV + IC = ERV + TV + IRV 3. f = respiratory rate = frequency of breathing 4. RV = residual volume = volume of air left after complete exhalation (can't find w/spirometer)

What are the functions of the circulatory system?

1. Transport: O2, CO2, absorbed nutrients 2. Endocrine: take hormones to target tissues 3. Excretory: take metabolic wastes to kidneys 4. Temp: vasodilation and vasoconstriction 5. Immune: leukocytes made/carried in blood

All ___ types of contraction generate ____, but if and how the muscle moves depends on how the ____ compares to the _____.

1. three 2. force 3. force it generates 4. force of the load

Heat

A type of *energy* measured in Joules (J) or calories - As ATP cycles during metabolism, heat is generated as a byproduct = higher metabolic rate leads to more heat produced

Temperature

Average *kinetic movements and vibrations* of molecules of an object measured in K, C, or F.

Ligament

Connects bone to bone

Tendon

Connects muscle to bone

Fascia

Connects muscle to muscle

If the load on a type 1 lever is moved closer to the fulcrum, would this increase or decrease the effort needed to hold the load up?

Decrease; if we shorten Lo while keeping Li and Fo the same, we would decrease Fi to keep the equation balanced

Role of actin in contraction

- The binding site of myosin heads - Myosin moves them along

Fast glycolytic fiber

- Contraction maintained only for a short time = calcium-ATPase pumps working hard to pump Ca back into the sarcoplasmic reticulum - Short burst of force - Chickens have it in their wings b/c they take flight only in danger. Sprinting muscles in fish. Gastrocnemius muscle in frog.

Slow oxidative fiber

- Sustained contraction possible = calcium pumps not working as hard as fast fibers so calcium concentration stays high for longer - Used for continuous sustained activity - Chickens have it in their legs b/c most of their time is spent walking. Fish have it in their cruising muscles, maintained constantly. Flight muscles in migratory birds.

Role of t-tubules in contraction

-Action potential moves into the t-tubules by the sequential opening of voltage-gated Na+ channels. -initiates calcium release from sarc. ret.

Role of ATP in contraction

-Binds to myosin head -allows for the power stroke in the contraction to occur

Motor unit

-Motor neuron + all the muscle cells it controls - 1 somatic motor neuron innervates multiple fibers, but each fiber is only innervated by 1 neuron - When somatic motor neuron fires, all muscle fibers in the motor unit contract

Complete tetanus

-Stimulus is closer together so muscle can't relax fully. -Ca++ can't be taken up quick enough between contractions - Increased frequency = more force b/c contractinon keeps on going.

Fast-twitch oxidative-glycolytic fiber

...

Type 2 Lever

-load is in the middle - The closer the muscle is from load/fulcrum, the more mechanical advantage -standing on tiptoe

Type 3 Lever

-muscle is in the middle - Mechanical disadvantage b/c effort is closer to fulcrum than load; effort must always > load - Closer the effort is to the fulcrum, farther the load moves. Farther effort = higher the load lifts. - Exp: tweezers or crane, biceps lifting something in hand

What muscles are used for forceful exhalation?

1. Abdominal muscles (push viscera in/up so diaphragm must go up) 2. Internal intercostal muscles (pull sternum and rib's sides down) - Lower volume = positive pressure outside lung

Antagonist vs. agonist pairs

1. Antagonist = muscles that move joints in opposite directions [i.e. flexor (bicep) + extensor (triceps)] - Flexor = brings connected bones closer together. Extensor = brings them farther away. 2. Agonist = muscles that work together to move a joint in the same direction

What happens in the cardiovascular feedback loop?

1. Arterial baroreceptors (in aortic/carotid bodies) send info about MAP vs. setpoint MAP to medullary cardiovascular center 2. Integrating center changes activity level of symp/parasymp neurons

Respiratory feedback loop

1. Chemoreceptors (in both the brain and aortic and carotid bodies) sense pH/CO2 level in arteries 2. Respiratory integrating center (pons/medulla) get input and compares w/setpoint value. Center neurons 3. Respiratory neurons lead somatic motor neurons that control skeletal muscles to ventilate the lungs = increased output/respiratory drive

What muscles are used in ventilation (inhalation and exhalation)?

1. Diaphragm = contraction makes it move down to increase thoracic cavity dimensions 2. External intercostal muscles = contraction makes muscles shorten which pulls the ribs to the sides to make bigger side dimensions - Exhalation = relax contracted inhalation muscle

How does cardiac feedforward regulation during exercise help your body?

1. Exercise detected so axons from motor cortex go to spinal motor neurons and medullary cardiovascular center 2. Sympathetic nerves activated = release NE to adrenergic receptors and cause adrenal gland to release epi to target organs 3. NE/epi = increased contractility = contract with more force = more blood ejected per beat = increased SV = increased systolic pressure 3. Sympathetic activity increases local resistance = lower organ blood flow = lower TPR 3. Slightly higher MAP (TPR down but Q greatly up) so feedforward increases the MAP setpoint

What are the functions of the circulatory system?

1. Gas exchange 2. Acid-base regulation 3. Vocalization

Exercise training

1. Higher preload (end-diastolic volume) = more blood fills heart during diastole so SV increases, more venous return and plasma volume 2. Higher contractibility 3. Lower afterload = less arterial constriction, more blood flow w/no change in MAP

IRV, ERV, IC, EC,

1. IRV = inspiratory reserve volume = volume inhaled after normal inspiration (normal peak to max peak) 2. ERV = expiratory reserve volume = volume exhaled after normal exhalation (normal trough to min/max exhale) 3. IC = inspiratory capacity = volume inhaled after normal exhalation (normal trough to max peak) = TV + IRV 4. EC = expiratory capacity = volume exhaled after normal inhalation (normal max to max exhale)

Respiratory feedforward during exercise

1. Motor cortex --> spinal cord --> medulla respiratory center --> increase ventilation before changes in CO2/pH occur (muscle makes more CO2 to metabolize fuel) 2. Higher intensity = more CO2 made = ventilation must increase so feedforward works after exercise begins to prevent too much or too little ventilation increase

What 3 factors control the amount of FORCE in an isometric contraction? Which factor did we test for lab 4, expt 2?

1. Muscle length - Force cannot reach max when myosin-actin overlap is above/below the "optimal range" 2. Frequency of stimulus - Affects [Ca2+] in the sarcoplasmic reticulum = more stimuli means continuous influx of calcium 3. Number of fibers contracting - More fibers active = more force

What 3 factors control the amount of FORCE in an isometric contraction? Which factor did we test for lab 4, expt 2?

1. Muscle length (no max force when starting overlap is above/below "optimal range") 2. Stimulus frequency (more stim = more Ca) 3. # of contracting fibers (more fiber = more F)

Relative VO2 max

= Mass-specific-VO2 max = VO2 max / weight - If 2 different-sized people have the same value for relative-VO2-max, then mass is the only factor causing the difference in their VO2-max's

White muscle

= fast glycolytic fiber - Gain ATP from anaerobic respiration (glycolysis) and produce lactate as result - Makes ATP fast but fatigues easily from lactate

LDH

= lactate dehydrogenase - Glycolysis enzyme found in cytosol - Found more in fast glycolytic than slow oxidative muscle

MDH

= malate dehydrogenase - Kreb's cycle enzyme found in mitochondria - Found more in slow oxidative (red) muscle than fast glycolytic muscle

OSV

= optimum stimulus voltage = lowest voltage that induces the largest amount of force - If stimulus voltage is too low, force will be too low - If stimulus voltage is too high, the muscle will be damaged

Red muscle

= slow oxidative fiber b/c of presence of myoglobin's reddish pigment - Gain lots of ATP from aerobic respiration (Kreb's cycle) - Low myosin-actin activity = sustained contraction

Summation

Action potentials are closer together so the muscle isn't allowed to relax fully and the muscle tension continues to add up (sum up).

Obstructive lung disease

Airflow resistance = can't exhale fully/quickly b/c exhale fast means bronchioles collapse and alveoli trapped (w/air inside) = inhalation normal - Exp: asthma, emphysema, pulmonary edema

Restrictive lung disease

Alveoli lose compliance = can't stretch/expand during inhalation = smaller FVC = normal exhale - Exp: TB, cystic fibrosis, pulmonary fibrosis, respiratory distress syndrome

Role of calcium-ATPase pump in contraction

Brings calcium back into the sarcoplasmic reticulum

Role of troponin in contraction

Ca++ binding site

Role of calcium in contraction

Calcium enters cytoplasm after release from sarc. ret. and binds to troponin, allowing actin-myosin binding and power stroke contraction

Conduction

Collision of molecules = heat transfer when two objects touch - Before conduction, objects vibrate at different levels. After, they vibrate at same level. - Exp: standing on a rug vs. standing on tile Rate depends on: 1. area = more area means higher energy and more heat transfer 2. temperature difference = greater difference is more energy transfer 3. thermal conductivity (k) = higher k means easier conuctivity so faster temperature change

Ankle antagonistic/agonistic pairs

Extend ankle: gastrocnemius vs tibialis anterior

Frog gastrocnemius function

Extends ankle

Lever equation

Fi x Li = Fo x Lo - Fi = force at insertion point - Li = length of lever arm in = length between Fi and fulcrum - Fo = force out (occurs at load, not at origin) - Lo = length of lever arm out = length between Fo and fulcrum

Lever equation

Fi x Li = Fo x Lo - Fi = force at insertion point (bone that moves) - Li = length of lever arm in = length between Fi and fulcrum - Fo = force out (occurs at load, not at origin) - Lo = length of lever arm out = length between Fo and fulcrum

Frog tibialis anterior longus function

Flexes ankle

Heat vs. temperature

Heat = *energy* in Joules (J) or calories Temp = average *kinetic movements and vibrations* of molecules of an object measured in K, C, or F.

Evaporation

Heat loss by conduction until water reaches skin temperature - Exp: sweating, breathing in/out of mouth Affected by: 1. surface area 2. temperature 3. relative humidity

Convection

Heat transferred between object and moving fluid (liquid/gas) - Exp: fan in computer or air heated/rises but then cools/descends and cycle repeats Rate depends on: 1. surface properties = bigger area means more energy transferred 2. temperature difference = larger difference allows more energy to be transferred 3. fluid properties (e.g. speed)

t5

Interval between max force and 50% of delta P

Latent period

Interval between stimulus application and start of the increase of force

Rise time

Interval between the start of the increase in force until it reaches a peak (max force)

Duration

Interval between the stimulus and t5

When do the "lub-dub" occur on an EKG graph, and what causes them?

Lub = when the AV (tricuspid and bicuspid) valves close = systole Dub = when the semilunar (aortic and pulmonary) valves close = diastole

Which side of the heart has thicker walls? Why?

Left side is thicker than right b/c systemic system is longer and must need more pressure to push the same amt of blood (as the pulmonary system)

Homeostasis

Maintaining internal conditions (e.g. temperature) relatively constant

MDH vs. LDH

Malate dehydrogenase = Kreb's cycle enzyme found in mitochondria, more more in slow oxidative (red) muscle than fast glycolytic muscle Lactate dehydrogenase = glycolysis enzyme found in cytosol, more in fast glycolytic

Delta P

Maximum force - resting force = force generated by the muscle due to cross-bridge cycling

M line

Middle accessory proteins that form attachment sites for thick filaments

T-test: paired vs. unpaired test

Paired = data from both sets came from the same person/object Unpaired = data from set 1 and 2 came from different people/things

Role of myosin in contraction

Myosin = motor protein that determines the speed of contraction - End of head has actin binding site + binding site for ATP - Converts ATP energy into crossbridge action mechanical energy - Head is elastic and pulls actin with it towards the M line, tail is stiff.

Radiation

Object absorbs/emits photons that each carry a certain amount of energy - Absorb = more vibration/energy - Emit = less vibration/energy Rate depends on: 1. Area = large area means more photons absorbed 2. Emissivity = higher emissivity means more photons absorbed/emitted per unit area 3. Wavelength/absolute temperature = higher temp means shorter wavelength means more vibrations/energy

Type 2 Lever

Resistance/load is in the middle. - The farther the effort is from load/fulcrum, the more mechanical disadvantage - Exp: wheelbarrow or nutcracker, standing on tiptoe *FRE123*

Stroke volume vs. cardiac output

SV = volume of blood ejected from 1 ventricle per heartbeat Q = volume of blood ejected from 1 ventricle per minute = SV * HR

How do we measure systolic/diastolic blood pressure? Order the blood vessels from highest to lowest pressure.

Sphygmomanometer measures large arterial pressure - Systolic = maximum when ventricles contract, diastolic = minimum non-zero when relaxed Aorta > arteries > arteriole > capillaries > venule > veins > vena cava

Lactate threshold

Sudden rise in lactate reached before VO2 max due to accumulation of lactate buildup as exercise intensity increases

When does systole and diastole occur during the EKG?

Systole = ventricular contraction, AV valves close = from Q to the end of the T wave (aka Q-T interval) Diastole = ventricles relax, makes semilunar close = end of T to start of P

Partial pressure of gas

Total pressure of a gas mixture * fraction of particular gas in mixture - Gases diffuse down their own partial-pressure gradients (go from higher to lower pressure), so diffusion is independent of other gases

Trace the branching of the lung from trachea to alveoli.

Trachea --> bronchi (primary -> 2ndary -> tertiary) --> bronchiole --> terminating bronchiole --> alveoli

Equilibrium

Transfer of heat energy from hot to cold until both objects are at the same temperature

VO2 equation

VO2 = 1.1 * VE * (FI O2 - FE O2) = rate of oxygen consumption (measure of metabolism)

VO2 max equation

VO2 max = HR max * SV max * (a-vO2) max = (220-age) * SV max * a-vO2 max = max capacity of the cardiopulmonary system to deliver oxygen to tissues - HR max * SV max = cardiac output - Maximum plateau in work rate vs. VO2 graph

Alveolar ventilation

Va = volume of air entering alveoli in one minute = (tidal volume - dead space) * respiratory rate

Independent variable

Variable that gets changed - In experiment, the indep. var. is the color of the frog models (white vs. black)

Minute volume

Ve = volume of air breathed in one minute = tidal volume (TV) * respiratory rate (f)

Dead space

Volume of air in lungs (conducting zones) that don't exchange gases - Bronchioles have thick walls = no gas diffusion

Dependent variable

What happens b/c the independent variable got changed - In experiment, the dep. var. is the heating rate.

Isotonic contraction

aka concentric = shortens length when contracting (Force of Muscle > Force of Load)

Role of sarcoplasmic reticulum in contraction

calcium channels on the sarcoplasmic reticulum release calcium after activated by action potential