exam 2 review a&p 1

prolapsed/herniated disk:

"pooching" out of the nucleus pulpous (prolapsed=knocked out of place)

What does Pr - stand for, and what is its relationship to potassium ion movement?

- Pr- means proteins which are negatively charged molecules that cannot cross the membrane and are trapped inside the cell -reason potassium gets moved back into the cell after it leaves through the leak channel

how-without a direct blood supply- are chondrocytes of the hyaline cartilage (that articulate between bones) allowed to conduct, gas, waste and nutrient exchange without a direct blood supply

- general rule is that 6-8 cell lengths have to be close to a capillary -hyaline cartilage is not vascularized, has no capillaries but do have living chondrocytes -chondrocytes facilitate diffusion of nutrients, oxygen etc -the articular (hyaline) cartilage is bathed in synovial fluid and has a sponge like composition and can gather nutrients through weeping lubrication

in a resting muscle cell, what does each of these terminal cisterns contain an abundant concentration of?

- terminal cisterns is "like a pitcher" -contains substance (calcium) that can pour fourth from them when it receives an action potential near them -calcium pours fourth

what is the term "potential" synonymous with as used by muscle physiologists and neurophysiologists?

-"potential" is synonymous with voltage -action potential=rolling wave of voltage -sudden, fast, transitory and propagating change of the testing membrane potential

what are the thin filaments made up of

-G actin molecules are an active protein condensed into spheres with active sites (myosin head binding sites) -tropomyosin is a dimeric protein that blocks the myosin head binding sites in the relaxed sarcomere -troponin complex is a trimer that regularly occurs ~90 nm to bolt the tropomyosin to actin -troponin is made of attachment proteins: calcium is the middle protein that pulls the other ends closer together -calcium moves tropomyosin to expose myosin head binding sites to bind thin filaments; myofilaments then slide past eachother when myosin binds

which myofilaments are directly connected to Z disks and which myofilaments is indirectly connected on either side by an enormous "spring like" polypeptide

-I hands (1/2 of them) are directly connected to Z disks therefore actin myofilaments are directly connected to the Z disks -The A band (thick filaments) is indirectly connected to the Z disk on either side by an enormous "spring like" polypeptide called Titin

what is the M line, where is it located, and what is its ultra structural significance

-M line is located within the H zone -M line is the attachment site for the thick filaments

what organism and cell type was initially used to measure a resting membrane potential and why

-a squid axón was initially used to measure a resting membrane potential because their axons are so fat (called giant axons) that they can be seen with the naked eye and a dissection microscope

under normal physiological circumstances, what factor(s) controls muscle cell contraction? is this true for smooth muscle? if not, can you think of a previously discussed example in which smooth muscle is not controlled by a neuron?

-action potential is the only way to have a contraction 1. must experience action potential moving down axon membrane 2. excitation occurs first which is coupled to contraction (excitation contraction coupling) -this differs for smooth muscle -previous example: oxytocin stimulates the contraction of uterine smooth muscle

what does the fibrocartilage in the knee do

-acts as a molding bridge of both ends of the epiphysis of articulating bones -acts as a shock absorber -improves fit between bones -limits degree of lateral excursion in the knee

methotrexate

-anti cancer drug -bad side effects at the dose of cancer patients -involves killing off fast growing cells such as cancer cells but also red blood cells and hair cells -at lower dose it can be used as an immuno-suppressant in replace of prednisone 1. first responders send message to radio in second responders 2. first responders produce cytokines, release them into the blood stream and this sends a "radio signal" to second responders 3. methotrexate acts as a "radio jammer" so the second wave never occurs

basic global function of skeletal muscle: posture

-baseline tension exerted at all times -majority of the muscles are actively engaged and consciously mediated (if you are standing and pass out you fall to the floor because you are no longer actively engaging)

fibrous: syndesmosis

-bones connected by a short ligament of dense CT that allows minimal movement to no movement -whether it is classified as amphiarthrotic or synarthrotic is a gray area (relates to the length of the ligament) -the longer the ligament the more flexibility, which brings the argument of it being amphiarthrotic -the shorter the ligament the more people classify it as synarthrotic Ex: radioulnar with the oblique cord being the rope like ligament and the interosseous membrane being the sheet like membrane

cartilaginous: symphysis

-bones covered with intervening fibrocartilage pad -amphiarthrotic -shock absorber Ex: intervertebral disks and pubic symphysis

how do elevated calcium levels in the sarcoplasm affect the myofilaments? more specifically, what does the elevated calcium interact with and what does this interaction change about the way the thick filament interacts with the thin filament?

-calcium levels stay high and myosin heads keep attaching and pulling the thin filaments, which in turn pulls the Z disks to shorten the sarcomere until it's completely shortened (maximum) -the calcium moves tropomyosin to expose the myosin head binding sites to bind thin filaments

basic global function of skeletal muscle: joint stability

-constant tension exerted at all times 1. snugness of fit 2. joint capsule and ligaments 3. muscle and muscle tendons that surround bc the joint (when you're awake your muscles help stabilize the joint) ex: rotator cuff muscles (4) help keep the humerus stable in glenoid cavity via baseline tension

bursae (plural)

-contain synovial fluid and provide cushion between structures that would otherwise rub against eachother and cause friction induced damage

is one of the drugs used to rheumatoid arthritis an anti-inflammatory steroid with almost identical physiology to one naturally produced by the adrenal glands?

-cortisone (ketone form) from prednisone and cortisol (alcohol form) have the same physiology -cortisone is a stress hormone like adrenaline (acute acting) it's just slower/ low grade chronic stress (cortisol) and lasts longer - might suppress the immune system which can make the individual more susceptible to infection/illness

rheumatoid arthritis:

-decides to attack synovial membrane -many diarthrotic joints of the appendicular skeleton can have this occur -rarest form of arthritis -no cure

know relative size of skeletal muscle cells and how they are formed from myoblasts

-each fascicle is a bundle of muscle fibers (cells) -each muscle fiber is long (> 1 cm) and wide (up to 0.1 mm) -formed by the fusion of myoblasts in embryo that donated their nuclei and cytoplasm -multiple myoblast nuclei maintained in each fiber sarcoplasm specializations -being multinucleated means they are incapable of doing mitosis, which is why skeletal muscle is poor at healing * myoblast=embryonic stem cell, "satellite cells"

what are the baseline characteristics of muscle fibers

-excitable -contractile -extensible -elastic

what is the significance of testing membrane potential in excitable cells

-excitable cells need voltage to create impulse -skeletal muscle and neurons use resting membrane potential to launch action potentials

gout or gouty arthritis

-happens more in males 1. ammonia is made (toxic) which quickly gets converted to urea (much less toxic, the kidney dispenses this in urine WNL) 2. DNA and RNA make nitrogenous waste (not very water soluble); purines= adenine and guanine, uric acid (hydrophobic) 3. when uric acid gets highly concentrated it crystallizes and can make uric acid "needles" (very painful) -in order to control uric acid build up you have to forego food heavy in uric acid

basic global function of skeletal muscle: thermogenesis

-heater -energy is not created or destroyed but it is transferable -when you transfer chemical energy stored in ATP into mechanical energy you lose some as heat -repeatedly contracting muscles can help warm the body

joints can be "ruined" as a result of ankylosis. however in 1963 a british orthopedic surgeon performed the first ______ replacement surgery. has this "joint replacement" technique been transferred to other synovial joints? how has it changed lives for patients?

-hip replacement surgery -yes it has been transferred to other synovial joints -a former crippling disease was now able to be replaced and resolve the patient of problems

if skeletal muscle is exposed to enough trauma to engender cell death, is it likely to heal at all, partially or entirely.

-if muscle cells are severely damaged and muscle cells have died you can still have some healing without pre-existing cells dividing -since you still have some myoblasts (satellite cells) scattered in the muscles, these can be stimulated to gather together and create new multinucleated skeletal muscle cells

what is the role of sodium potassium pump in establishing and maintaining the rating membrane potential

-important for constructing the resting membrane potential -the pump is churning out sodium outside the cell and bringing potassium in (going against their concentration gradient), creating a sodium gradient -energy required for the pump is ATP -pump has the ability to tap into ATP via hydrolysis so that energy is released -enzymes accelerate this process called ATP hydrolysis (ATPase=hydrolysis ATP as a pump) -pump cycle= 1 hydrolysis of ATP provides enough energy to go through one pump cycle

how is resting membrane potential measured? explain how it is standardized to a negative number

-it is measured using a voltmeter -the voltmeter is set to a "reference" voltage which would be 0 -the reference electrode is placed on the outside and the measurement electrode is placed inside of the cell -the resulting voltage was -70 mV

what else happens to the hyaline cartilage in osteoarthritis that can "gum up the works"

-it loses the "slick" surface that it typically provides potentially leaving bone-on-bone -can have the formation of bone spurs

what does cortisone normally do and how is it "anti-inflammatory"

-it normally suppresses the immune system to manage the flare ups but can also cause the person to become more susceptible to infection -cortisol can also get you sick because the immune system weakens when the body adapts to long term chronic stress

what is dentin

-made of collagen -soft tissue -has odontoblasts and gelatinous component -appears to have striations -as close as you can get to being bone without being bone

How do the terms extensible and elastic apply to ligaments vs. muscles ?

-muscle cells/fibers are extensible and elastic -ligaments are not really extensible or elastic, but they have some extensibility to allow for flexibility -if ligaments are stretched beyond 1-2% of its resting length the integrity of the joint can be compromised -ligaments are less elastic than a muscle cell

of the 4 tissue types, which ones are "excitable" and what does that mean?

-muscle tissue is excitable, this means it responds to stimulation and contracts to provide movement -muscle tissue occurs as 3 different types: skeletal, smooth, cardiac -nervous tissue is also excitable, meaning it allows nerve impulses to communicate with different regions of the body * only neurons and muscle cells are capable of generating an action potential

where does gout often "announce its presence"? does sex predispose one to gout? does diet play a role? if so, what dietary restrictions should perhaps be followed to ease the progression/occurrence of this condition?

-often found in the metatarsophalangeal joints (presents as warm to the touch/red) -males are more likely to get gouty arthritis -eating foods heavy in uric acid can contribute to the build up -try to avoid foods high in uric acid to ease the progression

fibrous: suture

-only found in the skull (exception is the temporomandibular joint) -dense fibrous CT between flat bones of skull (starts off with a lot of space proportionally but as the skull grows the space thins) -skull has fontanelles that become synostosis in 4th decade of life -at birth and right after birth the skull becomes amphiarthrotic (slightly moveable)

what do neurons connect to

-other neurons -glandular cells -muscle cells

what is a pannus and what is it's role in the progression of osteoarthritis?

-pannus is a type of overgrowth in your joints that can cause pain, swelling and damage to your bones -progresses osteoarthritis to the point it can be irreversible (ankylosis)

fibrous: gomphosis

-peg in socket fibrous joint -always a joint between a tooth and the mandible or maxilla connected to bone by periodontal ligaments

basic global function of skeletal muscle: movement

-produces tension to move things by squeezing, pulling etc -tension and pulling is allowed because the muscle is attached at 2 joints -more mobile point: insertion -less mobile point: origin

osteoarthritis

-progressive thinning of hyaline cartilage and the formation of osteophytes (bone spurs) -not an autoimmune disease because it has to do with hyaline cartilage -most common, tends to run in families -called "wear and tear" arthritis but can also be catalyzed by injury -synovial membrane is in tact

how does the term excitable apply to muscle cells

-respond to chemical and mechanical stimuli by generating organized movement of electrical charge across membranes: muscle potential or action potentials -tissues that are electrically excited and organize a rolling wave of change in voltage to create an action potential -neurons can initiate an action potential or controlled rolling wave of charge dispersal all the way to the axon , this then stimulates the release of the chemical called a neurotransmitter that diffuses through the muscle plasma membrane to bind to the proteins

Know the names of bands, discs and zones of a sarcomeres and how they are positioned with respect to each other in a relaxed sarcomere otherwise known as a sarcomere in 100% position.

-sarcomeres in tandem share Z disks -one 100% relaxed sarcomere is made of (from left to right): Z disk, 1/2 I band, A band, H zone (containing M line), A band, 1/2 I band, Z disk -the 1/2 I band is the region from Z disk to A band -the H zone is lighter than the rest of the A band

how does the term contractile apply to muscle cells

-shortening -can produce a lot of force

how does the term elastic apply to muscle cells

-snap back into position after being stretched -muscle cells/fibers are elastic

what two very important ion gradients does the sodium potassium pump create and maintain

-sodium ion gradient -potassium ion gradient

What 3 transmembrane proteins establish a resting membrane potential?

-sodium leakage channel -potassium leakage channel -sodium/potassium pump/ATPase

synovial:

-synovial joints are diarthrotic joints and diarthrotic joints are synovial joints -all synovial joints have a joint capsule made up of synovial fluid -all synovial fluid is made by synoviocytes Ex: knee

what are the common parts of all the synovial joints

-synovial membrane= made of synoviocytes that make synovial fluid -joint cavity= filled with synovial fluid that helps dissipate friction between the cartilage on the ends of long bones -joint capsule= has synovial fluid (raw egg like), wall of soft tissue that encapsulates the ends of the bones; the joint capsule is made of the synovial membrane and fibrous capsule -fibrous layer of joint capsule= rough dense irregular CT, provides tensile strength, welds to periosteum of bone, contributed to structural integrity of the joint *blood vessel and pain nerves create scaffolding through bone

why is dentin "bone like" but still is not identical to bone

-teeth are bone like and are often associated with the skeleton but they are actually part of the digestive tract -teeth are the hardest organs in the body -like bone without the fortification against brittleness from collagen

if a sarcomere fully contracts, how far in its contraction can it go, and why can it go no further

-the A band will stay the same length as when relaxed but the I band shortens and the H band completely disappears in contraction -when you maximally contract the sarcomere the two Z disks have been pulled maximally close together and the "spring" has been maximally compressed -the average muscle can only contract about 2/3 of their resting length

one of the ligaments is especially commonly injured and has a long name. because of this people often say or write its initial idk instead of its full name. what is it's full name and initialism that's shorthand for its long name?

-the ACL or anterior cruciate ligament is very vulnerable to injury -the MCL or medial collateral ligament is also easily injured -knee buckling puts immense stress on ACL which connects to the meniscus which connects to the MCL (unholy triad); this can lead to ligaments being torn by both compact and pivoting forces

how does an action potential, to the extent discussed in class up to this point, travel down and through a muscle cell. for the "through" part what structure conducts the action potential into the cell

-the action potential travels through the sarcolemma until it reaches a transverse tubule (T tubule) -T tubule is a tube with a pore that goes from one side of the muscle cell to the other; this is important because the sarcolemma is only a fraction of the width of the whole cell, so the action potential is brought into the muscle cell via the T tubule -action potential splits—> some continue through sarcolemma and some goes down T tubule

in general, what is a "chemical synapse" and why is it called that? from what structure is the "chemical released" and what is a general term for this type of chemical?

-the chemical synapse portion is where the action potential diffuses across to bind to the proteins on the target cell membrane -it is called the chemical synapse because the chemicals diffuse through it -the chemical is released from the axonal end -chemical generally is called a neurotransmitter

What two gradients can affect ion flow of an ion across a membrane?

-the electrical gradient (voltage) and concentration gradient counterbalance each other (for every few potassium that move out there are a few coming back in, if you waited there would be an equilibrium between the out and in until sodium would fix it) -concentration gradient= chemical gradient (synonyms)

how does rheumatoid arthritis start and potentially progress within the joints?

-the immune system (B and T cells) decides to attack the synovial membrane by secreting cytokine hormones, which causes the membrane to overproduce synoviocytes and that causes a build up -in advanced stages, the synovial membrane becomes pannus (overgrows) and invades the hyaline cartilage which causes the joint to fuse together and be incapable of movement. this is called ankylosis (need surgery)

what are the knees strengths and weaknesses as a joint

-the knee has move pivot ability (good) but that also creates a lack of stability (bad) -the knee is good/strong at being a joint (ex: you can carry and walk with someone elses weight on you) -the knee is a modified hinge joint because it has some lateral excursion, contains the patella (classified as a sesamoid bone) *sesamoid bones develop within tendons

understand the role of potassium leak channels and sodium leak channels play in establishing the resting membrane potential

-the large amount of potassium leaving through the potassium leakage channels establishes a chemical gradient due to them abandoning the Pr- cells and creating a more negative charge on the inside of the cell membrane (as soon as potassium leaks out, there is a disturbance in the electrical balance- the negative charge inside the cell triggers the need to suck it back in which establishes the electronegative gradient) -the electrical gradient is going to have a greater pull for potassium ions to come back in after they leak out

how does the development of skeletal muscle lead to formation of up to dozens of nuclei per cell?

-the myoblasts fuse and donate their nuclei to the skeletal muscle cell *skeletal muscle cells are pressed up against the plasma membrane

explain how a rectangle drawing of a sarcomere is a "stick figure" diagram at best

-the sarcomere is 3D in real life and the rectangle drawings don't allow us to see the hexagonal patterns that the myofilaments make in each band of the sarcomere

in a relaxed sarcomere, how is tropomyosin positioned with respect to the myosin head binding sites on actin and what holds it in this position

-the tropomyosin is blocking the myosin head binding sites -troponin holds the tropomyosin in this place until the calcium moves the tropomyosin by pulling the other ends closer together

know the basic structure of myosin and how it assembled to make up the thick filament

-thick filaments=myosin myofilaments -the A band contains both actin and myosin myofilaments but the H zone only contains myosin thick filaments -the thick filaments is made of two polypeptide chains (dimeric protein: "dimer") -single myosin polypeptide has a shape similar to a golf club (tertiary structure) -myosin needs 2 polypeptide stems to wind around one another to function (2 myosin chains, 2 globular heads to be thick filaments) -globular heads can swivel

cartilaginous: synchondrosis

-thin, synarthrotic plate of hyaline cartilage that unites bones Ex: epiphyseal plate and first costal cartilage of rib -epiphyseal union of diaphysis with epiphysis can be thought of as an "intra bone" joint (joint within a bone) -epiphyseal line formation marks the formation of a synostosis

how does the term extensible apply to muscle cells

-tolerate stretching -muscle cells/fibers are extensible

why/how tooth decay occurs and why it can never "heal" on its own

-tooth decay can come from getting older and not going to the dentist which allows bacteria pockets to form and ruin ligaments therefore loosening the teeth -scurvy (drop in vitamin C) affects the ligaments and makes teeth loosen in their socket -teeth are susceptible to acid when bacteria builds up and secretes acid in a microenvironment to erode the tooth enamel (dental cavity) * fluoride stabilizes hydroxyapatite to help prevent tooth decay -it cant heal on its own because the enamel cells died

Where does uric acid come from and how can its overpresence play into joint disease?

-uric acid is created when the body breaks down purines -uric acid is dissolved into the blood and excreted from the body as urine via the kidneys (WNL) -if a person produces too much uric acid or does not excrete enough it can crystallize and build up causing pain and inflammation in the joints surrounding the tissue leading to gouty arthritis

what is an autoimmune disease

-very unpredictable, widely variable in terms of severity, there is no cure but there are drugs you can take to manage it -people with autoimmune diseases have their own immune system turn against them and attack healthy tissues -normal healthy immune systems are supposed to attack foreign/domestic invaders but an unhealthy immune system can't fight those and can lead to serious outcomes (death) ex: type 1 diabetes, lupus, chrons disease, multiple sclerosis, vitiligo, eczema

what are the structural joint classifications?

1. Fibrous 2. Cartilaginous 3. Synovial

synchondrosis examples

1. acetabulum- hyaline cartilage between ilium, is john and pubic bones in child-teenage heats that will layer fuse to make one bone 2. epiphysis- hyaline cartilage bridging between the epiphysis and diaphysis making a joint 3. manubrium to first rib (costal cartilage)- makes synchondrosis

skeletal muscles will only react to:

1. must have action potential going to axon 2. must have axon release neurotransmitter and travel across synaptic cleft 3. must have transmitter bind to muscle cells to activate them 4. these then activate the muscle cell synapse to create its own action potential that moves both directions down the muscle cell called the MUSCLE POTENTIAL

examples of symphysis

1. symphysis pubis- fibrocartilage surrounded by hyaline cartilage with a symphysis on each side (females have a more flexible pubic symphysis bc of childbirth) 2. intervertebral disks- L1 has fibrocartilage in the middle then L2 (nucleus pulpous and anuins fibrosis )

what are the functional (degree of movement) joint classifications?

1. synarthroses= immovable joints 2. amphiarthroses= slightly moveable joints 3. diarthroses= freely moveable joints

what are the ligaments in the knee called?

ACL or anterior cruciate ligament PCL or posterior cruciate ligament medial meniscus MCL or medial collateral ligament LCL or lateral collateral ligament

what are some examples of NSAIDs

Aspirin, ibuprofen, naproxen sodium (Advil, Motrin, aleve)

what is the perimysium

CT that separates fascicles from one another (surrounds fascicles)

For each ion, what is the direction of the gradient and how does this relate to the difference of concentrations on either side of the membrane?

EXAM: pumps 3 Na- out and 2 K+ in -potassium concentration gradient flows to the outside of the cell -sodium concentration gradient flows into the cell -there are more potassium channels per square area of membrane than sodium leak channels -sodium leaks down from high to low concentration -potassium leaks from inside high concentration to low concentration

be able to describe the NMJ (what does this stand for) in very basic terms

NMJ= neuromuscular junction it is the space where the end of the axon comes into close contact with the sarcolemma

what is another name for the sodium/potassium pump

Na+/K+ ATPase

what are NSAIDs and how may they be used in treating arthritis?

Non steroid anti inflammatory drugs, to treat pain and swelling in the affected joint

what is a triad

T-tubule plus 2 terminal cisternae. (specifically the terminal cisterna and cistema)

what is a sarcomere

a collection of organized myofilaments

what is an anabolic hormone

a hormone that promotes growth

what is an "articulation" in anatomy

a joint(s)

what is the building block of the thin filament

actin

what is the origin of troponin

actin end (won't move)

what are the thin filaments

actin myofilaments

what filaments are found in the A band (not including the H zone)

actin thin and myosin thick filaments

what filaments are found in each 1/2 I band

actin thin filaments only

the thin filaments is made of two strands of

actin wound around one another; this creates scaffolding for other things (tropomyosin) to attach to it

what is another more technical term for "nerve impulse"

action potential

what does the nernst equation allow you to do if you know the outside and inside concentrations for an ion

allows you to determine the exact electrical gradient that will balance the concentration gradient of what is outside vs inside the cell

what is a muscle fascicle

always a collection of muscle fibers/cells which is a cylinder within a cylinder

what is the plural for amphiarthrosis

amphiarthroses

intervertebral disks are

amphiarthrotic

pubic symphysis is

amphiarthrotic

when a synapse is activated from the release of a neurotransmitter, what does this induce on the sarcolemma of the muscle?

an action potential is induced in the motor end plate

Define ankylosis and when and under what condition(s) does it occur?

ankylosis is a severe case where the joints get fused together, immediately destroying the joint -high risk in rheumatoid arthritis -can also occur in osteoarthritis

what are intracapsular ligaments

are inside the capsule to make connections (anterior crucial ligament and posterior cruciate ligament)

what does "arthro" indicate

arthro refers to joints (ie arthritis= inflammation of the joints)

the only multiaxial joint type is

ball and socket

why is the "atomic unit" designation appropriate (for sarcomere)

because it is the smallest unit of muscle contraction

synovial structural classification

bone ends covered with articular cartilage and enclosed within a capsule lined with a synovial membrane

define syndesmosis

bones connected by a ligament (fibrous)

define symphysis

bones covered with intervening fibrocartilage pad (cartilaginous)

cartilaginous structural classification

bones joined by cartilage (bridging tissue) with the absence of a joint cavity

what forms tendon sheaths

bursae that extend along tendons for some distance

what do these terminal cisterns "pour fourth"

calcium

the sodium/potassium pump directly makes a relatively small contribution to the resting membrane potential due to its "electrogenicity", but it makes a huge indirect contribution by providing the ________ gradient that leaks back and forth through the ________ leakage channels

concentration; potassium *sodium/potassium pump is indirectly responsible for everything (always there and on even if not illustrated) -it builds and establishes concentration gradients making inside more negative and outside more positive

what are periodontal ligaments

connect tooth to alveolar bone

for skeletal muscle, what is contraction predicated on?

contraction is predicated on action potential

define sarcoplasm

cytoplasm of a muscle cell

synovial joints are classified as ______.

diarthroses

what is the plural for diarthrosis

diarthroses

what is meant by a "flare up" of an autoimmune disease

during a "flare up" your autoimmune disease is active and your antibodies are in the process of attacking your own body; effector T cells are viewing parts of the body as invaders and attacking them

what are myofibrils

each cylinder within a muscle cell -myofibril is the "train" and the sarcomere are the cars on the train

fibrous structural classification

either dense regular or dense irregular connective tissue

why is enamel more brittle than bone

enamel is more brittle than bone because it is made of pure hydroxyapatite while bone is made of both pure hydroxyapatite and soft tissue

what wraps around and forms the "outer skin" of a fiber

endomysium

what wraps around and forms the "outer skin" of the muscle

epimysium

what is the term used to specify the membrane potential that exactly counterbalances the chemical gradient so that the two gradients are in "equilibrium" with one another

equilibrium potential

what is an "electrogenic pump", name a relevant example and explain why it's called electrogenic

ex: sodium potassium pump (must have this otherwise nothing works) -called electrogenic because it hydrolyzes ATP and uses that energy released to "pump" or transport ions across the membrane -establishes an electrochemical gradient from movement of ions inside and outside of the cell

which happens first "excitation" or "contraction"?

excitation (prerequisite for muscle contraction)

regarding teeth what is their structural joint classification, sub classification and degree of movement

fibrous structural classification gomphoses is subclassification synarthrotic (no movement) *can be amphiarthrotic if the tooth is loose

what different types of joints allow the possibility of synostosis to eventually occur

fibrous sutures and cartilaginous synchondrosis (epiphyseal plate and first costal cartilage)

what are the layers of the tooth

from superficial to deep: enamel, crown, neck, root, pulp

define synostosis

fusion of bones together due to growth

what is ankylosis

fusion of joints, cause stiffness and rigidity

what are extracapsular ligaments

goes around the capsule to make connections (medial collateral ligament)

in a real cell, there are other ions that can also simultaneously contribute to the overall resting membrane potential besides potassium of any other single ion. is there another equation that accounts for the other contributing ions (though it's contribution is significantly less than potassium)

goldman equation

this equation that is essentially an expansion of the nernst equation and weights other ions proportionally to their permeability and individual equilibrium potential and is called the

goldman equation *goldman equation has permeability coefficients that give a weighted average (favors potassium so measured potential is closer to potassium)

define synarthrosis

immovable joint

what is bursitis

inflammation of a bursa and may cause pain around the joint and restrict movement

what is the most famous hernia

inguinal hernia located: lateral and superior to the genitalia much more common in men because they have a weak inguinal

what is the meaning of the nernst equation if you know the outside potassium concentration and the inside potassium concentration

it is the equilibrium potential for potassium -you can plug in the concentration and you can calculate the electrical gradient that is going to oppose that concentration gradient of what is outside the cell vs inside the cell

what drug used to treat rheumatoid arthritis is also an anti cancer drug? how is it effective in treating an autoimmune disease? how does this drug work?

methotrexate is an anti cancer drug and is effective in treating autoimmune diseases by suppressing the immune system at low doses; methotrexate acts as a roadblock when the cytokines try to signal for a second wave

what is the relationship between a muscle fiber and a muscle cell

muscle cell=muscle fiber (synonyms)

prefixes sarco- and myo- mean the term is specific to

muscle cells or proteins originally found in muscle

a muscle cell is also called a

muscle fiber (synonymous)

know the "cylinders within cylinders" nesting of contractile elements from large to small and from small to large within a muscle

muscle going from relaxed to contracted: -whole muscle contracts because the muscle fascicles are shortening -the muscle fascicles are shortening because the muscle fibers are shortening -the muscle fibers are shortening because myofibrils are shortening -myofibrils contract because the sarcomere contracts -the sarcomere contracts because the myofilaments actin & myosin are sliding past eachother

when the myofibers slide past eachother the ________ shortens

myofibril

name the equation: EK+= (RT/zF)ln[K+]i/[K+]f

nernst equation (computes the equilibrium potential)

can you see muscle cells/fibers

no

is there a difference between the term "concentration gradient" and "chemical gradient"

no

are all muscle cells/fibers contractile?

no -some are stretch receptors that when stretched create an action potential to communicate the degree of stretch with the nervous system (proprioception from joint capsules and muscle cells/fibers)

is ankylosis exclusive to rheumatoid arthritis? if not explain

no, if severe enough it can also happen in osteoarthritis (just less common)

are autoimmune diseases curable

no, there is no cure

do ions like to move through membranes

no, they are hydrophilic, they can however be moved through membranes if there are leak channels (for both potassium and sodium)

why do muscles have strong vascularization

on demand the have to take chemical energy and make mechanical energy, it needs blood supply for mass amounts of oxygen to perform this

what filaments are found in the H zone (located within the A band)

only myosin thick filaments

For what joint disease is continued thinning of hyaline cartilage a central cause?

osteoarthritis

what type of arthritis is widely experienced by the aging population? is there a genetic component?

osteoarthritis; genetic component—> tends to run in families

what are osteophytes and what disease are these commonly associated with?

osteophytes are bone spurs and are commonly associated with osteoarthritis

what is the epimysium

outer CT that enshrouds entire muscle (surrounds muscles)

what wraps around and forms the "outer skin" of a fascicle

perimysium

define sarcolemma

plasma membrane of a muscle cell "plasmalemma"

what drugs can be prescribed to help manage rheumatoid arthritis

prednisone (cortisol) or a low dose of methotrexate

what does the term proprioception mean and how does it relate to joint anatomy/physiology?

proprioception= holistic sense that allows us to know how our body is moving and positioned in space being communicated via stretch receptors in the joint -prime example of anatomy and physiology being interconnected (inner ear gives special important information about the head moving in space)

define myofilaments

protein filaments only made in muscle cells (actin and myosin)

what is enamel made of

pure hydroxyapatite (waterless calcium phosphate salt)

in general, can autoimmune diseases be very predictable in their progression or can they be quite unpredictable

quite unpredictable

What joint disease falls into the autoimmune category?

rheumatoid arthritis

is there one condition in particular where the risk of ankylosis is particularly high?

rheumatoid arthritis

of the 3 types of arthritis, which has the reputation of being the most crippling if left untreated

rheumatoid arthritis

what are the joint diseases discussed in class

rheumatoid arthritis, osteoarthritis, gout or gouty arthritis

what is the "atomic unit of contraction"

sarcomeres

what organelle are terminal cisterns or a terminal cistern a part of

sarcoplasmic reticulum (smooth ER of muscle cell) -very close to T tubule with a thick portion welded to the T tubule

what is another name of a skeletal muscle cell?

skeletal muscle fiber

what is the generalized way hernias occur

something soft is contained within a tough outer wall, if there is a weakness in that wall it can rupture and the "soft stuff" (such as the nucleus pulpous) inside will "pooch" out

what is "weeping lubrication"? what are 2 functions

squishing the hyaline cartilage sponge, releases synovial fluid, when compression stops the fluid gets sucked back in—> this allows chondrocytes enough time to get what they need before going back into the hyaline cartilage "sponge" 1. allows chondrocytes to conduct gas, waste and nutrient exchange without direct blood supply 2. dissipates the friction between the distal and proximal end of 2 long bones by releasing synovial fluid into the joint cavity

what is the endomysium

surrounds each skeletal muscle cell/fiber in a fascicle (surrounds muscle fibers)

define a synostosis?

sutural synostosis= fusion of soft tissue called fontanlles to form sutures synostosis= when you have bones and it grows together to make one bone (ossification)

what is the plural for symphysis

symphyses

what is the plural for synarthrosis

synarthroses

Fibrous joints are classified as ________.

synarthroses (amphiarthrotic exceptions)

cartilaginous joints are classified as _______.

synarthroses and amphiarthroses

sutures are

synarthrotic

synchondroses are

synarthrotic

gomphoses is

synarthrotic (amphiarthrotic if teeth are loose)

radioulnar syndesmosis is

synarthrotic or amphiarthrotic depending on ligament length

define synchondrosis

synarthrotic plate of hyaline cartilage that unites bones (cartilaginous)

what is the plural for synchondrosis

synchondroses

what is the plural for syndesmosis

syndesmoses

regarding structural classification, is there any structural sub classification that can be ambiguous in terms of its movement classification? if so, which one and what parameter tends to make it more likely to be classified as amphiarthrotic compared to synarthrotic

syndesmosis (fibrous) can be ambiguous in terms because it can be either synarthrotic or amphiarthrotic depending on ligament length -longer ligament makes it more likely to be classified as amphiarthrotic by allowing some movement due to flexibility

what is the plural for synostosis

synostoses

what is the relationship between synovial joints and diarthrotic joints? what about vice versa? for such joints, what is the relationship between joint stability and joint mobility?

synovial joints are diarthrotic joints and vice versa (freely moving) ex: interphalangeal joint THE GREATER THE MOBILITY THE LESSER THE STABILITY

are the maximally compressed spring like proteins maximally compressed or maximally extended in tetanus?

tetanus is the maximum amount Titin can be compressed and the maximum amount the sarcomere can shorten (tetanic contraction)

what is a synaptic cleft

the gap from the axon and the binding sites of a muscle (motor end plate)

titin is

the largest polypeptide and is 30000 amino acids long yet still functions as a single polypeptide

the equilibrium potential for potassium is -90 mv and for sodium is +65 mv, but the actual measurable resting membrane potential is ~-85 mv. what is the explanation for why the overall resting membrane potential is not a equally weighted average between Ek and ENa?

the nernst equation only accounts for the specific ion concentrations of either potassium or sodium, and does not account for the many other electrically charges molecules within and outside a cell that affect a resting membrane potential (such as sugars, ATP etc)

Is a continued attempt to use the joint ipso facto bad for this type of "wear and tear" arthritis? why is "wear and tear" kind of a misleading description of osteoarthritis?

the phrase "wear and tear" makes people assume that they need to "baby" the joint and that it only occurs over time, when it can actually be catalyzed by an injury and the joint needs to be kept active

Define sarcoplasmic reticulum

the smooth endoplasmic reticulum of a muscle cell

what is excitation contraction coupling time?

the time it takes from action potential to contraction force

what factors do all 3 joint diseases have in common?

they all involve inflammation of joint (arthritis); progressive in a sense can cause pain and swelling

What do odontoblasts do?

thicken dentin as you age

when you're born you have all the skeletal muscle cells you're ever going to have, how is this possible

this is allowed by the hypertrophy of cells; getting bigger and longer aided by growth hormone

why is there no regeneration process for erosion/cavities

tooth enamel cells are completely gone (have died)

why is it that if you break or chip a tooth in which there is dentin exposed, that this can cause so much discomfort even though the pulp of the tooth is not directly exposed

trigeminal nerve 3 is in this area, chipping a tooth exposed naked dentin with fluid and when pressure is applied on the columns in the dentin the pain nerve is triggered

what is the insertion of troponin

tropomyosin ends (will move)

true or false: the pulp of the tooth is soft

true

true or false: in teenage years you have anabolic steroids

true -gold standard= testosterone -during puberty men produce 20% more testosterone which aids growth

what is a resting membrane potential

voltage platform/floor from which you can launch an action potential

how do the terminal cisterns react to having an action potential moving down an adjacent T tubule

when the action potential passes through the T tubule the terminal cisterns sense it and release calcium

what state is this maximally compressed polypeptide said to be in?

when the titin polypeptide is maximally compressed it is in tetanus

are fascicles visible with the naked eye

yes

can autoimmune diseases be managed to some degree

yes, by drugs (such as prednisone or methotrexate)

is one of the rheumatoid arthritis drugs essentially a high dose of a human hormone ? if so, what is the rationale for using it to control a disease like rheumatoid arthritis?

yes, prednisone is a high dose of the human hormone cortisol; it is used to help control diseases like this by suppressing the immune system by preventing flare ups

can the nernst equation be used for other ions besides potassium

yes, sodium

does diffusion of the neurotransmitter occur across a synaptic cleft? if so what does it diffuse toward?

yes, the neurotransmitter diffuses towards the protein within the muscle membranes (on sarcolemma) of the target cell

do all cells have a resting membrane potential

yes. all cells (whether muscular or neuron) have a resting membrane potential (voltage)

considering only one ion at a time: is there an equation that equates the chemical gradient with the electrical gradient that will be established to exactly counterbalance the electrical gradient? what is the name of this equation?

you can plug in concentrations into the Nernst equation to calculate the electrical gradient that opposes the concentration gradient