Lab final

in a ______ of a skeletal muscel fiber we find myofilaments composed of thick filaments constructed of ______ and thin filaments made of _____.

in a ______ of a skeletal muscel fiber we find myofilaments composed of thick filaments constructed of ______ and thin filaments made of _____.

myofibril

myosin

actin

how do we electrically record muscle activity?

through an electromyogram

muscles of the human body contract following the….

sliding filament theory

when a skeletal muscle is initiated to contract, the width of the _____ gets smaller

I band

the contractile unit of a muscle is called a

sarcomere

the primary function of muscle is to convert _____ energy into _____ energy

chemical to mechanical

a skeletal muscle subjected to the glycerination process :

permits investigation of muscle contraction with the addition of ATP and ions to initiate the contraction process

also removes ions and ATP from the tissue, disrupting regulatory proteins so that binding sites on actin are no longer blocked

a somatic motor nueron and all the skeletal muscle fibers it innervates is called a

motor unit

organization of a skeletal muscle

myofilaments, myofibril, muscle fiber, fascicle, muscle

label the sarcomere

sliding filament theory

actin filaments are pulled centrally when the myosin crossbridges bind to the actin filaments

for a muscle fiber to contract, what must first happen

myosin heads must first be activated by ATP

Contraction process

signals received by NS

release of Ca ions from the sarcoplasmic reticulum

Ca interacts with troponin which moves the tropomyosin on actin to allow activated myosin heads to bind

myosin head with ADP and P binds to actin

Phosphate released- power stroke

ADP released and ATP binds, detaching myosin head

ATP hydrolyzes

electromyogram

the detection, amplification and recording of changes in skin voltage produced by underlying skeletal muscle contraction

used to dx neuropathies and myopathies

signal is consequence of propogation of motor nerve impulses and their transmission at the nueromuscular jxns and propagation of muscle impulses by the sarcolemma and t tuble resulting in excitation contraction coupling

glycerinated skeletal muscle

glycerin creates holes in sarcolemma → removes ions and ATP and disrupts regulatory proteins so that binding sites on actin are no longer blocked

no Ca or ATP found here

length tension relationship

too flexed- myofilaments are too close together and cannot generate enough force to contract well, start associating too close together

too relaxed- myofilaments are too far apart to form cross-bridges

a muscle generates the most force when it is at a medial length

muscle fatigue

reduction in ability of muscle to generate force as a result of previous contractile activity

glycerinated muscle contraction with salts and ATP

we can conclude that the addition of ATP and salts in a muscle needs to occur at the same time for optimal contraction

how is muscle movement related to an electrical signal

muscle fibers are innervated by a motor neuron which means that when the motor neuron is activated, the muscle fibers associated with it respond by generating their own electrical signals that lead to the contraction of the muscle fibers

relationship btwn strength of muscle contraction and amount of electrical activity generated

higher energy produced= higher strength of muscle contraction

more energy is produced by your muscles when they are extended

hand position and muscle activity

higher muscle activity is seen with extension and flexion

lower muscle activity is seen when the muscles are at rest

grip strength in dominant vs nondominant hands

dominant hand is usually stronger

gender and grip strength

males have stronger grip strength than females

grip strength in fingers

the grip strength decreased from the index to the pinky

least difference was from index to middle, most difference from middle to pinky

force and hand position

hand position determines how much the actin and myosin fibers overlap each other and couse the muscle to either shorten or lengthen

flexion and extension produced the least muscle force, no angle produced the most muscle force

weight and muscle fatigue

muscles fatigue quicker when weight is added

explain muscle loss and stroke

loss of blood flow→ lack of muscle function

stroke causes issues in communication btwn the muscle and the brain causing them to no longer work normally

how does a muscle know how much force is required to perform an action?

motor neurons can signal for how much force the muscle needs to in order to perform a task.

what causes difference btwn fingers and pinch strength

frequency of fingers used and dominant hand

functions of blood

carry O2 and nutrients to the cells in organs

remove wastes

contribute to hormonal and temperature regulation

protection via clotting and defense mechanisms (immunity)

cellular portion of blood

formed elements

formed elements include

erythrocytes, leukocytes and thrombocytes

hematocrit

the proportion of blood that consists of RBCs

expressed as percentage

higher the HCT, the more RBC available to transport O2

normal: 41-53% in males, 36-46% in females

low HCT term

anemia

high HCT term, high altitudes and chronic smokers

polycythemia

differences in human blood type due to

antigens on surface of RBC

granulocytes

neutrophils, eosinophils and basophils

agranulocytes

lymphocytes and monocytes

the _____ are reservoirs for venous blood and the _____ are the major pumping chambers for delivering blood to pulmonary and systemic circulation

atria, ventricles

path of electricla conduction in the heart

SA node→ AV node→ atrioventricular bundle→ atrioventricular bundle fibers → purkinje fibers

ECG

measures the electrical activity of the heart through electrodes on the skin

changes in ECG due to interruptions of electrical signal generated or its transmission

computes the difference btwn positive and negative electrodes and displays changes in voltage differences with time

negative to the positive

the direction of activity during the cardiac cycle

mean electrical axis (MEA)

bipolar lead

lead composed of 2 discrete electrodes of opposite polarity

lead axis

hypothetical line joining poles of a lead

einthovens law

lead 1 + lead 3= lead 2

einthovens triangle can be collapsed to create an axial reference system

ECG vectors

length- magnitude of current

orientation- direction of current flow

tip of arrow- positive pole

base of arrow- negative pole

plot lead 1 and lead 3 to find MEA(direction) and mean potential of the heart (length)

left axis deviation

btwn -30 and -90

results from conditions that cause the left ventricle to take longer than normal to depolarize

right axis deviation

btwn 90 and 180 deg

can be normal in people with long narrow chests but in many adults is associated with damage to conduction system in right ventricle

total RBC count

normal: 4.5 to 5.9 million/mm³

layers of heart wall

fibrous layer, parietal layer, pericardial cavity, visceral layer, myocardium, endocardium

P wave

atrial depolarization

QRS complex

ventricular depolarization and atrial repolarization

t wave

ventricular repolarization

PR interval

delay in electrical activates of ventricles after SA node fires

ST interval

entire cardiac muscle is depolarized

QT interval

ventricular systole

avg HCT for males

41-55%

avg HCT for females

36-46%

what factors can influences the R wave

height and limb length

low WBC count

low immune respons

high WBC count

autoimmune disease

airflows through the conducting zone of the respiratory system and into the respiratory zone due to

a pressure gradient

residual volume

the volume of air left in the lung after the max exhalation

categories of pulmonary disorders

restrictive and obstructive

where does the respiratory zone begin

the external nares and ends at alveoli

what is spirometry

medical test that measure the volume of air an individual inhales or exhales as a fxn of time

asses normal lung fxn and capacity

dx of disease

help monitor progression of disease and effectiveness of treatment

tidal volume

volume of air inhaled or exhaled with each breath during normal breathing

inspiratory reserve volume

max vol of air inhaled from the end inspiratory tidal position

expiratory reserve volume

max volume of air that can be exhaled from resting end-expiratory tidal position

total lung capacity

sum of all volume compartments or vol of air in lungs after maximum inspiration

inspiratory reserve vol + tidal volume + expiratory reserve vol + reserve volume

vital capacity

total lung capacity minus reserve volume

or

inspiratory reserve vol + expiratory reserve vol + tidal vol

inspiratory capacity

sum of inspiratory reserve vol and tidal volume

spirometry normal values depend on

height, age, gender, and ethnicity

when does the diaphragm contract?

inspiration, contracts down

functional residual capacity

volume of air remaining in the lungs after a normal exhalation

expiratory reserve vol + residual volume

what is 1

tidal volume

what is 2

inspiratory reserve volume

what is 3

expiratory reserve volume

what is 4

residual volume

what is 5

vital capacity

what is 6

inspiratory capacity

what is 7

functional residual capacity

what is 8

total lung capacity

difference btwn lung volumes in males and females

women have proportionally smaller airway size and lungs than men so they typically have a lower vital capacity than men

total minute volume calculation

tidal volume * breaths/min

represents that amount of air inhaled or exhaled from a subject in 1 minute

how does breath holding affect tidal volume, respiratory rate and total minute volume?

inc in tidal volume and total minute volume

dec in resp rate

how does rapid breathing affect tidal volume, respiratory rate and total minute volume?

dec in tidal volume, resp rate and total minute volume

how does excercise affect tidal volume, respiratory rate and total minute volume?

inc in tidal volume and total minute volume

dec in resp rate

what would happen to the expiratory reserve volume when you are treading water?

dec in expiratory resrve volume

what happens to the lungs during emphysema?

In severe emphysema, due to the destruction of lung tissue and reduced recoil, the

total lung capacity will either be the same or slightly increase because the lungs can lose their elasticity and can maybe hyperinflate or not which can cause some issues with exhalation and trapped air.

The tidal volume would decrease due to the decreased recoil and contraction issues which will cause agony in breathing or dyspnea as the lung and individual finds difficulty to accommodate air and breathe properly.

During ________ blood pressure drives the movement of water and dissolved substances through the fenestrations ad filtration slits of the filtration membrane . This basic component of renal function occurs in the ________. In _______ we observe about 99% of useful solutes being reclaimed from the glomerular filtrate and returned to the blood. This basic component component of renal function primarily occurs in the _______. Unwanted substances like urea and creatine, are transported from the blood back into the renal tubule, this process is called ______ and occurs mainly in the _______.

glomerular filtration, renal corpuscle, tubular reabsorption, proximal convoluted tubule, tubular secretion, distal tubular secretion

nephron

functional unit of kidney

responsible for urine formation

comprised of renal corpuscle and renal tubules

filter blood to form filtrate

reabsorption

from lumen of nephron to blood

occurs in proximal convoluted tubule, loop of henle and distal convoluted tubule and collecting duct

glucose, amino acids and bicarbonate

secretion

from blood to lumen of nephron

occurs in PCT, DCT, and collecting duct

removes wastes such as urea, uric acid, and creatinine; drugs such as penicillin, aspirin, and morphine; and excess ions such as H+, K+ and

HCO3-.

filtration

occurs in renal corpuscle

resulting from hydrostatic pressure of blood pushing fluid out of the capillary wall of the glomerulus producing filtrate

contains same molecules as plasma minus proteins

passive process

urinalysis

checking appearance, conc and content of urine

used to detect and manage a wide range of disorders such as UTI, kidney disease and diabetes

central role of kidneys

regulate volume and chemical composition of body fluids

influences blood plasma, IF and lymph

glomerulus

tightly woven, highly permeable capillary bed at end of afferent arteriole

inner visceral layer of the glomerular capsule covers the glomerulus, epithelium is composed of podocytes with foot-like processes called pedicels that interdigitate to form filtration slits.

the outer parietal layer is separated from the inner visceral layer by the capsular space

Both layers of the glomerular capsule are composed of simple squamous epithelium.

renal tubule

a convoluted tubule lined by epithelial cells

countercurrent multiplier

the nephron loop/loop of Henle, and it establishes the osmotic gradient