Review Questions Exam 1
Name the four types of cells which make up bone.
fibroblasts chondroblasts osteoblasts hematopoietic stem cell
Where are the adult stem cells found in bone? And what color?
Adult stem cells are found in bone marrow. Red?
What is composition of the epiphyseal growth site?
An outer shell of compact bone forms the epiphysis exterior, the interior contains spongy bone, a thin layer of articular (hyaline) cartilage covers the joint surface of each epiphysis
Do osteoclasts do work aerobically or anaerobically?
Anaerobically
What is the connective tissue of the heart?
The Cardiac Skeleton; it's thickened fibrous connective tissue to support the valves
What type of cartilage covers the ends of bones and why is this type of cartilage significant for covering the ends of bones?
hyaline cartilage (articular cartilage) because it provides support with flexibility and resilience
Why is episodic stress beneficial to bone?
increase in bone mass
What is a disadvantage to 2nd class levers?
less range of motion and speed
Synovial joint stability can be determined by a combination of five factors. Name 3 of them.
shapes of articular surfaces number and positioning of ligaments muscle tone
How do you describe a shortening of muscle cells?
shortening occurs if and when the cross bridges generate enough tension on the thin filaments to exceed the forces that oppose shortening (when the myosin heads lose ADP + phosphate) sarcomere shortens
What are the 4 phases of contraction and heartbeat and relate them to pressure changes at the valves mentioned in class?
----Ventricular filling (mid-late diastole) & Atrial Contraction: Pressure in heart is low, blood returning from circulation is flowing passively through atria and open AV valves into ventricles (80% of ventricular filling happens now, other 20% is delivered to ventricles when atria contract). Aortic and Pulmonary valves are closed. Following depolarization, atria contract, compressing blood in their chambers; ventricles are in last part of their diastole and have maximum blood volume (end diastolic volume- EDV). Atria relax and ventricles depolarize. ----Ventricular ejection: ventricular pressure continues to rise; when it finally exceeds that of the pressure in the large arteries, the isovolumetric stage ends as the semilunar valves are forced open and blood rushes from the ventricles into the aorta and pulmonary trunk. During this phase, the pressure in the aorta normally reaches about 120 mm Hg. ----Isovolumetric relaxation (early diastole): Brief phase where the ventricles relax; because the blood remaining in their chambers (end systolic volume- ESV) is no longer compressed, ventricular pressure drops rapidly and blood in the aorta and pulmonary trunk flows back toward the heart, closing the semilunar vavles; this raises aortic pressure. This is where the dub sound is heard as the turbulent of blood hitting the valves.
What is the body's capacity to hold blood? Why do we only have 5-6 L?
---12-15 L ---If body was filled with blood, 12-15 liters: --Increased body weight,15-22 lbs more --Increased heart size, pump against > pressure & volume --Increased energy to maintain heart
Describe the differences between the vena cava and the aorta.
---Aorta-carries oxygenated blood away from the heart to the whole body ---Vena cava-carries deoxygenated blood from the body to the heart
Describe the control for blood flow to the brain after sudden increases or decreases in pressure and what is responsible for sensing these changes?
---Baroreceptors: in your aorta, and other areas such as the carotid artery ---Sympathetic Nervous System --Signal goes to your brain and sends out the appropriate response ---increase in pressure, arteries dilate to allow the blood to escape. low pressure, the arteries constrict to increase your blood pressure.
How are cardiac muscle cells connected and in what kind of network? Why is this important?
---Cardiac muscle is striated and contracts by sliding filament mechanism, but have short, fat branched and interconnected cells; intercellular spaces are filled with a loose connective tissue matrix (endomysium) containing numerous capillaries that's connected to the fibrous cardiac skeleton. ---The plasma membranes of adjacent cardiac cells interlock like the ribs of two sheets of corrugated cardboard at the junctions called intercalated discs. ---Intercalated discs contain anchoring desmosomes and gap junctions. ---Desmosomes prevent adjacent cells from separating during contraction ---Gap junctions (more specifically called connexons) allow ions to pass from cell to cell, transmitting current across the entire heart to allow electrical coupling of cardiac cells so they can behave as a single unit or functional syncytium.
What are the problems associated with this kind of hypertrophy (pressure overload)?
---Inadequate perfusion of LV ---Conductance problems ---Ischemia
How does pressure overload affect the left ventricular?
---Increase in Left Ventricular mass due to increase afterload (blood pressure) ---Increase in Left Ventricular mass and wall thickness without increase in Left Ventricular volume
What is pericarditis and how does this affect the heart?
---Inflammation of the pericardium of the heart ---Inflammation of the pericardium that roughens the serous membrane surfaces. As the beating heart rubs against its pericardial sac, it creates a creaking sound (pericardial friction rub). ---Characterized by pain deep to the sternum ---May lead to adhesions in which the visceral and parietal pericardia stick together and impede heart activity over time. ---In severe cases, large amounts of inflammatory fluid seep into the pericardial cavity that compresses the heart and limits its ability to pump blood (called cardiac tamponade).
What is the Valsalva maneuver?
---Performed by moderately forceful attempted exhalation against a closed airway, usually done by closing one's mouth, pinching one's nose shut while pressing out as if blowing up a balloon ----Four phases: --Initial blood pressure rise --Reduced venous return and compensation --Pressure release --Return of cardiac output
What are the differences between the three components of the cardiac output at rest vs. exercise?
---Q = SV * HR (amount of blood pumped per minute) ---At Rest ---Q = 70 ---SV = 70-80 ---HR = 5,000-6,000 mL/min ---Exercise (maximal work) ---Q = 220-age ---SV = 110-120 ---HR = 22-24 L/min
Describe the difference between vasodilation and vasoconstriction.
---Vasodilation means the smooth muscles in your blood vessel walls relax causing them to widen. This widening results in less vascular resistance, thus the blood flowing through the dilated vessel increases. Vasodilation may occur locally or system wide. ---Vasoconstriction means the smooth muscles in your blood vessel walls contract causing them to narrow. This action results in blood flow through your vessels to be restricted.
What releases the Ca++ once the sarcoplasmic reticulum is depolarized and what does that Ca++ bind to?
---action potential travels down T-tubules causing tubule proteins to change shape, opening the Ca release channels in the terminal cisterns. Ca then travels into cytosol where it attaches to troponin. ---TERMINAL CISTERNAE OF SR RELEASE CA2+, THEN BIND TO TROPONIN
Describe the difference between fine and gross motor movements at the motor unit.
---fine → small amount of fibers/unit (ex: muscles controlling eye movement ~ 5 fibers/neuron) ---gross → example: large thigh muscles ~ 100-1000+ depending on fiber type
Explain burn severity using the rule of nines?
---rule of nines- divides the body into 11 areas each accounting for 9% of total body area, area surrounding genitals accounting for 1% ---Burn are considered critical following these guidelines --over 25% of body has second degree burns --over 10% of body has third degree burns --there are third degree burns of the face, hands, or feet
Define Subluxation.
--A slight misalignment of the vertebrae, regarded in chiropractic theory as the cause of many health problems. --A partial dislocation of the joint
During crossbridge formation, what occurs during the power stroke?
--ADP and Pi are released and the myosin head pivots and bends, changing to its bent low-energy state --Resulting in a pull of the actin filament toward the M line
In order for a muscle to relax, two primary things need to occur within the muscle cell. What are they?
--ATP binds to myosin head and causes its release from actin --Ca++ is pumped back into the SR
At the neuromuscular junction, how is acetylcholine stimulated for release and what does it bind to?
--Action Potential and voltage gated Ca2+ channels. --It binds to sarcolemma ACh receptors.
Describe the differences in diameter down the arterial tree and back up the venous side.
--Arteries have more SM & elastic tissue --Arterioles mainly have SM --Capillaries, venules, veins --High elasticity at the start, and it decreases as you go down -Getting further and further away from the heart --Arteries will expand in order to maintain blood pressure
What are common causes of vasodilation?
--Exercising --Gets blood back to your heart
Explain the four stages of healing after a fracture.
--Hematoma formation (mass of clotted blood) at fracture site. Tissue in fracture site swells, very painful, obvious inflammation, and bone cells are dying. --Fibrocartilaginous callus develops over a 3 to 4 week period. This process involves:capillary growth in the hematoma->phagocytic cells invading and cleaning-up debris in injury site->fibroblasts and osteoblasts migrating into site and beginning reconstruction of bone --Bony callus begins forming after 3 to 4 weeks after injury and is prominent 2 to 3 months following the injury. Continued migration and multiplying of osteoblasts and osteocytes results in the fibrocartilaginous callus turning into a bony callus. --Remodeling. Any excess material of the bony callus is removed and compact bone is laid down in order to reconstruct the shaft. Remodeling is the final stage
What is meant by low affinity and high affinity? What causes this?
--Low Affinity: When there is low affinity for something, it means that there is no attraction between the two. For example, there is low affinity for myosin head attachment to actin if there is no calcium present. --High Affinity: High affinity means there is much attraction. For example, when calcium saturates the troponin, it moves it allowing for myosin attachment and consequently there is high affinity for myosin head attachment.
Tendinitis and Bursitis are both types of inflammation. Which one is typically caused by overuse and which one is usually caused by a blow or friction?
--Tendinitis is caused by overuse --Bursitis (inflammation of the bursa) is caused by a blow or friction
What is the general structure of a synovial joint?
--articular cartilage- absorb compression placed on joint --joint cavity- potential space that contains a small amount of synovial fluid --articular capsule- encloses the joint cavity --synovial fluid- occupies all free spaces within the joint capsule, slippery, weightbearing film that reduces friction between cartilage --reinforcing ligaments- reinforce and strengthen synovial joints --nerves and blood vessels- synovial joints are supplied with sensory nerve fibers that innervate the capsule, some detect pain but most monitor joint position and stretch
Explain the steps of long bone growth.
--chondrocytes undergo mitotic division on epiphyseal side --chondrocytes become calcified and are replaced by bone on diaphyseal side --long bone growth continues until epiphyseal growth plate ceases and is replaced by bone (injury or puberty)
What do cartilaginous discs do and where can they be found?
--found in some, not all, synovial joints --function: increase surface area, decrease force per unit of cartilage, and take up compressive forces
What is the composition of compact bone?
--haversian canal- central unit of blood and nerves; runs longitudinal --volkmann canal- lateral to central unit, contains blood and nerves --canaliculi- hair like cells on central unit that allow for diffusion of nutrients, waste, hormones, etc. --lacunae- "little lakes" between lamellae that contain osteocytes --lamallae- concentric rings of bony matrix --osteocyte- mature bone cell
Name the five types of bone and give an example of each.
--long bones- all limb bones except the patella and the wrist and ankle bones --short bones- bones in the hands and foot --flat bones- sternum (breastbone), scapulae (shoulder blades), ribs, and most skull bones --irregular bones- vertebrae and hip bones --sesamoid bones - patellae (kneecap), some in hand/wrist/foot - bones that develop in tendons where there is high stress/friction
Explain the importance of good bone vs. osteoporotic bone in the femoral neck in terms of withstanding biomechanical stresses.
--osteoporotic bone--the composition of the matrix remains normal but bone mass decreases and bones become porous and light,bone resorption is faster than bone deposit --In good bone normal density is achieved by restraining osteoclasts and promoting deposit of new bone
What is pCa?
--pCa is the negative log of Ca++ concentration --pCa is similar to pH --Lower number = higher Ca++ concentration; Higher calcium concentration = more tension/force
What is the functional unit of a muscle fiber?
--sarcomeres compose myofibrils which compose the muscle fiber. --sarcomere
What is a purpose of the integumentary system?
--to protect the body --helps regulate body temperature --detects sensation --retain body fluids
Explain the hormonal control of calcium with the parathyroid hormone and calcitonin.
--when blood levels of calcium decline, PTH is released, increased PTH level stimulates osteoclasts to break down bone, which releases calcium into the blood --When blood levels of calcium are high, the thyroid gland releases calcitonin, which stimulates the deposit of calcium salt onto bones. when calcitonin is given at pharmacological doses it does lower blood calcium levels temporarily
What are the 3 main steps regarding muscular relaxation.
-ATP binds to myosin head and causes its release from actin -Ca2+ is actively pumped into the sarcoplasmic reticulum -Troponin allows tropomyosin to interfere with actin-myosin interaction
Name 4 important functions of epithelial tissue & provide at least one example of a tissue that exemplifies each function.
-Absorption - Simple Columnar (lines digestive tract to absorb nutrients from food) -Diffusion - Simple Squamous (lines air sacs of lungs to diffuse O2 and CO2) -Physical protection - Stratified Squamous (lines mouth to protect against abrasions) -Expansion and recoil - Transitional Epithelial (lines bladder to stretch for urine storage)
Name and describe the function of connective tissue.
-All tissues arise from a common embryonic tissue, mesenchyme -Function: Transportation, protection, insulation, storage -Type -Connective tissue proper (cells- fibroblasts, fibrocytes, defense cells, adipocytes) -Loose connective-dense connective (regular and irregular) -Cartilage (chondroblast and chondrocytes, avascular) -Bone -Blood
What is the function of the sweat glands and what is excreted?
-Also known as Sudoriferous glands: True sweat: 99% water, salts, vitamin C, antibodies, dermcidin (attacks bacteria on skin), metabolic wastes -Eccrine → more numerous and abundant, prevents body from overheating -Apocrine → secretes basic components of true sweat plus fatty substances and proteins, viscous milky/yellowish color, BO
Define a synarthrotic joint and where these are located?
-An immovable joint -Sutures (bones of skull) -Gomphosis- tooth in jaw, Sternum, Rib 1, epiphyseal plate
Describe the correlation between Myosin ATPase and the velocity of shortening.
-As the concentration of Myosin ATPase increases, the velocity of shortening increases -POSITIVE correlation
Explain bicuspid vs. tricuspid and where these valves are located.
-Bicuspid: Located between the left atrium and ventricle (it's the left AV valve). Has two cusps (flaps of endocardium reinforced by connective tissue cores) -Tricuspid: Located between the right atrium and ventricle (right AV valve). Has three cusps.
Provide examples from the body that illustrate four of the major functions of connective tissue.
-Binding and Support - proper, dense regular; attaches muscles to bones or bones to muscles -Transportation - elastic dense connective; maintains pulsatile flow of blood through arteries -Protection - hyaline cartilage; serves as a resilient cushion; resists compressive stress (covers ends of long bones in joint capsules) -Insulation - connective adipose; insulates against heat loss; under skin in subcutaneous tissue; around kidneys and eyeballs
Describe the circulatory system of the heart and what issues present when circulation to portions of the heart are occluded.
-Blood Flow: 1) Blood enters RA from superior and inferior vena cava & coronary sinus 2) Through TRIcuspid valve & into RV 3) Expelled through pulmonary SL & into pulmonary trunk (R & L pulmonary arteries) 4) Gas exchange occurs in lungs, returns through R & L pulmonary veins & into LA 5) Through bicuspid/mitral valve & into LV 6) Expelled through aorta through aortic SL valves and out to the body 7) O2 rich blood delivered to tissues, CO2 picked up 8) Blood enters RA again -Coronary arteries come off the aorta and feed the heart tissue -When circulation to portions of the heart are occluded: The heart needs high blood flow in order to get high amounts of oxygen; irregular coronary blood flow (clogged artery) can lead to fibrillation, heart attacks, or anginas as the cells are deprived of the needed amount of oxygen. A bypass can be done that runs a stint/vessel to go around the clogged area.
Explain the differences between bursitis and tendonitis.
-Bursitis= trauma, blow or friction, inflammation of bursa -Tendonitis= overuse, inflammation of tendon sheath
Explain the differences and effects of PTH and calcitonin on bone
-Calcitonin is produced by the thyroid and serves to build up or strengthen bones, it activates the osteoblasts, producing a decrease in calcium concentration. -PTH or the Parathyroid Hormone is produced by the parathyroid gland and serves to increase calcium concentration by activating the osteoclast, which break down bone.
What is osteonecrosis of the femoral head and how does this affect the decision of a hip replacement?
-Death of bone cells due to lack of blood supply in the femoral head. -Increases need for replacement due to the arthritis and pain from collapse of articular cartilage -If advanced to femoral head collapse this is the most successful treatment
What is the difference between dense regular connective tissue and dense irregular connective tissue?
-Dense regular- allows movement in one direction, found in tendons -Dense Irregular- allows movement in multiple directions, found in joints and dermis
How does the recruitment of motor units differ during walking down the stairs compared to walking up the stairs?
-Down--just enough so we don't fall down, but not enough to keep us from stepping down, going with gravity -Up--enough to propel our mass up against gravity
Briefly summarize the mechanisms of excitation -contraction coupling
-Electrical discharge at muscle initiates chemical events at cell surface; Cell releases Ca2+ -Muscle action results
Does the number of melanocytes differ between people? Does the amount of melanin secreted differ between people?
-Everyone has a similar amount of melanocytes. -Yes. Depends on prolonged sun exposure and the amount of melanin created by it. Melanocytes of dark people produce many more and darker melanosomes and keratinocytes retain it longer.
How do type II fibers relate to myosin ATPase activity and aerobic capacity?
-Fast Twitch Fibers -high capacity to transmit ATP -high myosin ATPase activity -rapid calcium release and uptake by sarcoplasmic reticulum -high rate of cross bridge turnover -capable of high force generation -rely on anaerobic metabolism
What is fiber type based on?
-How fast myosin ATPase binds to myosin and hydrolyzes ATP. -Contractile and Metabolic characteristics -Type 1: Slow Twitch, Oxidative -Type 2a: Fast Twitch, Oxidative -Type 2b: Fast Twitch, Glycolytic
What is the problem with malformation of valves or disease states that cause dysfunction of valves?
-It could lead to not enough blood being pumped out and thus decreased amount of work load that a person can do. -Could also lead to a heart murmur. -Leaky valves in the lower extremities can also lead to varicose veins (Incompetent veins, distension of veins - distension and valve has been stretched and blood can pool) -When blood stops moving, it clots -Clots can then break free and cause damage in heart, lungs and brain -Can strip the veins (take them out) to remove danger
Why is there an intricate connective tissue network in skeletal muscle?
-It's a chain reaction -As one muscle cell contracts it pulls on the connective tissue of another cell and this results in contraction signal reaching the tendon
List the various types of bone found in the body.
-Long- femur -Short- metacarpals -Flat- sternum -Irregular- vertebrae -Sesamoid- knee cap
The sensations of touch & pressure are picked up by receptors located in the ____________________.
-Meissner's corpuscles and tactile discs in dermal papillae (touch) -Pacinian corpuscles in hypodermis (pressure)
Are muscles adaptable to altered function?
-Yes -Example: endurance trained athletes- their stroke volume is significantly higher than regular people because of their training
What are the differences between a hematopoietic stem cell and a mesenchymal stem cell? - In function and in lab use.
-Mesenchymal stem cells, or MSCs, are multipotent stromal cells that can differentiate into a variety of cell types,[1] including: osteoblasts (bone cells),[2] chondrocytes (cartilage cells),[3] and adipocytes (fat cells). -Hematopoietic stem cells (HSCs) are the blood cells that give rise to all the other blood cells and are derived from mesoderm. They are located in the red bone marrow, which is contained in the core of most bones.
Name the two types of arthritis. Which one does Lupus fall under?
-Osteoarthritis -Rheumatoid Arthritis (Lupus, autoimmune)
What are the different types of joints? Review them on the physical flashcards
-Plane-nonaxial-gliding -Hinge-uniaxial-flexion/extension -Pivot-uniaxial-rotation -Condylar-biaxial-flexion/extension, abduction/adduction -Saddle-biaxial-flexion/extension, abduction/adduction -Ball and socket-multiaxial-flexion/extension, abduction/adduction, rotation
Define angina
-Refers to a situation where a person feels pain or uncomfortable sensation in his chest. -It takes place when part of the heart does not receive enough oxygen because of either blocked arteries or some disease in coronary arteries. -This lack of blood means heart muscles get deficient in oxygen and other nutrients.
What is the age limitation of hip replacements? What is the reasoning behind this? When would you see hip replacement done in younger people?
-Reserved primarily for patients over 60 years of age since they only last for 10-15 years. -Younger patients: Severe Injury
What is the function of the SR?
-SR = Sarcoplasmic Reticulum -It regulates the amount of Ca+ in the cell. It stores calcium and releases it to initiate muscle contraction.
What determines the stability of a synovial joint?
-Shape of articular surfaces (determines what movements are possible) -number of ligaments (prevents excessive and undesirable movement) -muscle tone -joint capsule -accessory structures (meniscus, labrum)
How do type I fibers relate to myosin ATPase activity and aerobic capacity?
-Slow Twitch Fibers -low myosin ATPase activity -slower calcium release and uptake by sarcoplasmic reticulum -low glycolytic capacity -large and numerous of mitochondria
Why is the size principle important in regards to neurotransmitter saturation?
-Small recruited first-lower intensity of stimulus-less Ach -Greater intensity-Greater Ach-larger cell body -Small cell bodies (slow twitch) get recruited first because they are saturated with signal quicker (depolarize faster)
Explain the differences between sprains, dislocations, subluxations and injuries to cartilage.
-Sprains: ligaments reinforcing a joint are stretched or torn; HEALS SLOWLY -Dislocations: when bones are forced out of alignment; often accompanied by sprains and inflammation -Subluxations: partial dislocation of a joint -Injuries to cartilage: when meniscus is subject to compression and shear (parallel to surface) stress at the same time, DOES NOT HEAL
Define tetanus
-Stimulation frequency continues to increase as well as muscle tension until it reaches maximal tension -All evidence of muscle relaxation disappears and contractions fuse into a smooth, sustained contraction plateau. Happens infrequently -Can't continue indefinitely because leads to muscle fatigue
What regulates formation of goosebumps? What muscles are responsible for them? How does heat stress relate to formation of goosebumps?
-Sympathetic nervous system- Exposure to cold, dehydration w/ elevation of core temperature, emotional stress -Arrector pili -Prevents heat loss
Which joints have a capsule around the joint are and which ones do not?
-Synovial joints have capsules -fibrous (sutures) and cartilaginous joints (between symphesis pubis vertebrae) DO NOT
What happens with hyaline cartilage as you age? How does this relate to arthritis? How are compressive forces affected?
-Tends to calcify and heal very slowly, dehydrates. Arthritis is pain from the lack of proper cartilage protection/absorption of the bone -Compressive forces inflict more damage
What determines heart rate? Which part of the heart does this happen in?
-The SA node -Right atrium
Explain the depolarization through the heart starting at the atria and ending through the ventricles
-The SA node or pacemaker sets the beat of the heart in the right atrium -Depolarization travels through atrial cells (cell to cell connections) through the Bundle of Bachman to the left atrium where both contract at the same time -Depolarizes to the AV node (it has a slower velocity to allow for complete filling of the ventricles) -Signal to Bundle of His -Down to Purkinje Fibers where they innervate the ventricles and papillary muscles
Define myocardial infarction
-The condition when blood supply to the heart is stopped because of blood vessels carrying blood to the heart. -When heart does not get enough oxygen, heart muscles die or get permanently damaged. -Also called heart attack in common parlance and normally occurs when coronary artery is blocked as plaque surrounding arteries gets ruptured.
Name and describe the function of epithelial tissue.
-The only avascular tissue (endothelial covers organs) -Functions: Forms boundaries between different environments, protection, absorption, filtration, excretion (passive) & secretion (active), sensory reception -Types--simple, stratified, pseudo stratified: columnar, cuboidal, squamous
Describe the differences and explain the reasoning behind the differences in wall thickness of the right and left ventricle.
-The right ventricle has significantly less myocardium than the left ventricle -Because the left ventricle must be able to push the blood to travel to the entire body -The right ventricle only needs so much pressure to make it to the lungs for the pulmonary system.
What does the size of the motor neuron have to do with generating force? What is this idea called?
-The smaller the motor neuron, the less stimulus needed to activate it -The larger the motor neuron, the more fibers it will innervate and greater amount of Ach it'll send, and therefore the more force it will generate. -Size principle
When does the ventricle relax?
-The ventricle relaxes during the isovolumetric relaxation phase or diastole -Following the T wave
Describe Rigor Mortis
-There is a low amount of ATP -High affinity of Myosin for Actin -Ca2+ can't be taken up by sarcoplasmic reticulum because Ca2+ uptake is an ATP dependent process
What are the three subunits of Troponin and what do they do?
-TnI: the inhibitory subunit that binds to actin -TnT: binds to tropomyosin and helps position it to actin -TNC: binds to calcium ions
Define incomplete tetanus
-When a stimulus strength is held constant and muscle is stimulated at an increasingly faster rate: -The relaxation time between twitches becomes shorter and shorter -The concentration of calcium rises higher and higher -The degree of wave summation becomes greater and greater producing a sustained but quivering contraction
What is fibrillation? How does one fix it?
-When the heart looks like a bowl of jello jiggling.. small vibrations from the heart caused by stress. -Paramedics fix this with a defibrillator.
Can the heart beat outside of the body? Why and in what conditions?
-Yes, because it has pacemaker cells (like the SA node) that can initiate their own as well as other cells' depolarization, allowing the heart to beat. -
What is hydroxylapatite?
-calcium and phosphate complexed together -give bone hardness -inorganic portion of bone
What is the function of calcium phosphate in the bone?
-complexed as hydroxyapatite -provides hardness to bone (inorganic material)
What type of epithelial tissue lines most of: digestive tract, esophagus, respiratory tract, alveoli, urinary tract organs, endothelium
-digestive tract-simple columnar -esophagus-stratified squamous -respiratory tract-pseudostratified columnar -alveoli-simple squamous -urinary tract organs-transitional -endothelium-simple squamous
Explain the difference between eccentric, isometric and concentric contractions.
-eccentric: lengthening -isometric: no shortening of muscle -concentric: shortening
What is the importance of cartilaginous discs in some synovial joints? What does it do in regards to surface area? Why is surface area important?
-increase surface area = less pressure per unit cartilage -takes up compressive forces
At what angle is the lamellae collagen fibers laid down in the lacuna and why is this beneficial?
-oblique angles- helps to reduce impact from all angles -torsion strength (resists fracture when there is twisting of bone)
What is the range of angles of pennation typically found in humans?
0 to 30 degrees
What happens to bone when there is a low level of calcium is detected?
1) PTH is released 2) which stimulates osteoclasts to degrade bone with hydrolytic enzymes and release CA+2 until homeostasis is reached. *How to get it back up* ------Because osteoclasts have an anaerobic metabolism, they create lactic acid that will lower the pH in its surroundings → stimulates more osteoclasts to break down bone. the bones release calcium to bring it back to a good blood level.
name and explain the stages cells go through to become mature osteocytes
1) osteoprogenitor cells - stem cells that are differentiated to become bone 2) osteoblast - mitotic division, lay down extracellular material 3) osteocyte- mature bone cell in lacuna
How long do hip replacements typically last?
15-20 year
If you stretched actin and myosin within a sarcomere, at what length would you have no overlap?
3.7 um (180% of optimal length)
The organic portion of bone comprises _____% of bone mass, whereas the inorganic portion of bone encompasses ________%?
35% 65%
Define Twitch
A motor unit's response to a single action potential of its motor neuron -muscle fibers contract quickly and then relax Latent period-->period of contraction->period of relaxation
What is a triad regarding skeletal muscle?
A triad is formed when a T-Tubule is flanked on either side by the calcium containing Terminal Cisternae of the Sarcoplasmic Reticulum.
What is a cisterna? ( looks like the golgi apparatus)
A vessel where Ca2+ is sequestered or released
What is actin made up of and what does it form?
Actin is made up of two strands of actin subunits twisted into a helix plus two types of regulatory proteins: troponin and tropomyosin
What two things are Rigor Mortis dependent on?
ATP and Ca2+
Energy for the sliding-filament model of muscular contraction is provided by ____________.
ATP hydrolysis
What neurotransmitter is most responsible for initiating muscular contraction?
Acetylcholine
When do epiphyseal growth plates fuse?
At 18 for females, 21 for males (after puberty)
What is the AV node and why is it important?
Atrioventricular Node: Here the impulse is delayed for about .1s to allow atria to respond and complete their contraction and let ventricles fill up.
Which joint will have the most. amount of degradation to the hyaline cartilage?
Ball and socket
Which type of joints permit the most freely moving synovial joints
Ball and socket joint - the Multiaxial joints
Explain increasing muscle mass and speed of shortening using the example of Barry Bonds given in class.
Before, Barry Bonds was scrawny and didn't have that much muscle, which meant that his velocity against the resistance (bat) was slower than when he was shooting it up and he gained muscle. When he gained muscle, the velocity against the bat was higher meaning he can generate more force faster, which helped him hit so many home runs.
What is meant by the term "autoimmune"?
Body attacks itself, mistakes self as foreign and harmful
Is bone a dead tissue? If so, why? If not, why?
Bone is living hard connective tissue made up from a ground substance, or matrix and bone cells. These canals carry nerves and blood capillaries so that bone is a living tissue.
Describe the difference between bradycardia and tachycardia. What are pathological situations seen with each?
Bradycardia → slow heartbeat Tachycardia → fast heartbeat
How does a physical therapist or orthopedist determine between Bursitis and tendonitis?
Bursitis hurts in passive motion and tendonitis hurts in muscle activity
Can you make a muscle faster? Why or why not? What is involved to do this?
Can not increase muscle's max velocity of shortening, but can increase speed of shortening against same resistance (increase muscle mass)
_____________ expedites the removal of heat and metabolic byproducts
Capillarization
What happens with excessive sun exposure in regards to skin damage?
Causes elastic fibers to clump (leathery skin) and can alter DNA of skin cells leading to skin cancer
What effect does Ca++ have upon troponin?
Causes troponin to change shape, in turn removing the tropomyosin blockade on the myosin binding sites
What are the functions of the cilia? How do they differ from flagella?
Cilia- mobility, short sweep and recoil, many Flagella- long and few, wave like motion
Which joint is considered unique, but similar to a hinge joint?
Condyloid joint His joint hinges, but also can move left and right slightly
What type of tissue is bone?
Connective
What is an intercalated disc?
Dark staining junctions where adjacent cardiac cells interlock to anchor them together as well as act as a passageway for ions to travel with the desmosomes and gap junctions it provides.
Since epithelia are avascular, what layer would be expected to have the best-nourished cells?
Dermis (reticular layer)- has rich supply of blood vessels and nerve fibers
Each sarcomere has how many triads?
Each has 2 triads (near zlines)
What type of joint is your wrist?
Ellipsoid/condyloid joint
_____________ wraps each muscle fiber, while _____________ surrounds several fibers and forms bundles of fasciculi.
Endomysium Perimysium
What is the effect of regular exercise on joint health and structure?
Exercise that coaxes joints through their full ROM is the key to postponing the immobilizing effects of aging on ligaments and tendons, to keeping cartilages well nourished, and to strengthening the muscles that stabilize joints; postpones osteoarthritis
T/F) Osteocytes are usually metabolically active.
False
T/F. ATP bound to myosin gives myosin a high affinity for actin.
False
T/F. For each individual myosin head, four actin filaments surround it.
False
T/F: Cartilaginous disks are found in all synovial joints
False
What are three types of fibers found in connective tissues?
Fibrous collagen elastic (like in large blood vessels) Reticular (interconnecting network)
Explain a second class lever
Fulcrum--load--effort Advantage-force Disadvantage-speed and range of motion i.e. raising onto your toes
During contraction, which fibers and zones shorten and which fibers and zones stay the same?
H zone- shortens I band- shortens A band- stays the same
Which type of cartilage is most plentiful in the body?
Hyaline
Describe the relationship between load and velocity regarding muscle contraction
Inverse relationship Greater load = slower velocity; Less load = Greater velocity
What is important about the epiphyseal plate?
It's where the bone's growth occurs
What portion of the osteon is limited due to diffusion distance from the blood vessels?
Lamellae
What causes an ACL injury? How does this affect the stability of the knee?
Lateral blows to the extended knee; forces tear the tibial collateral ligament, medial meniscus, and ACL
What type of injury is most dangerous to the extended knee?
Lateral blows, ACL Tear
Explain a third class lever
Load--effort--fulcrum Advantage--range of motion and speed Disadvantage--force i.e. bicep curl
Describe the function of sebum.
Lubricates skin and hair, prevents water loss from the skin, acts as bacterial agent
In medial and lateral meniscal injury, which one is most common?
Medial
How are joint mobility and stability related?
More stability= less joint mobility and vice versa
Name and identify the 5 layers of the epidermis
Most superficial to least -stratum corneum -stratum lucidum-this is only in thick skin -stratum spinosum -stratum basale
Why is having your hair cut painless?
No nerves, consists of dead keratinized cells
Do striae (stretch marks) tan? Why or why not? Where are striae seen?
No. Contains no melanocytes. Seen after extreme stretching of the skin.
What happens on the descending limb of the curve on the length/tension graph?
On the descending limb of the curve, the sarcomere is getting longer meaning that the tension is lessening
What happens with age in regards to hyaline cartilage?
Ossification-the process of laying down new bone material by osteoblasts
Define Pennation.
Pennation is the arrangement of muscle fibers at oblique angles to the central tendon. Each individual pennate fiber has less strength than a parallel muscle fiber, but pennate muscles allow for more fibers and greater overall muscle strength. Drawback: Pennate muscles have less flexibility (less range of motion).
Describe the function os nervous tissue.
Primary tissue of CNS. Carries a depolarizing signal through nerves from dendrites to axons
What is the function of synovial fluid?
Provides a slippery, weight bearing film that reduces friction between cartilages
How do calcium levels increase within a muscle cell?
Release from the SR
What are Perkinje fibers?
Responsible for going out around the ventricles and eliciting that contraction
What are the resting and contraction sarcomere lengths?
Resting: 4 um Contracting: 1.6 um
What is rigor mortis?
Rigor mortis is one of the recognizable signs of death, caused by chemical changes in the muscles after death, causing the limbs of the corpse to become stiff and difficult to move or manipulate.
What type of cells make up capillaries and how many layers of cells are there?
Simple Squamous Epithelial One layer (thin for gas exchange)
Define amphiarthroses. How much movement does this joint have? Where would you find these in the body?
Slightly moveable, vertebrae
Does the heart have a skeleton? If not, why. If so, why?
The cardiac skeleton consists of four bands of dense connective tissue, as collagen, that encircle the bases of the pulmonary trunk, aorta, and heart valves. While not a "true" skeleton, it does provide structure and support for the heart, mainly valves, as well as isolating the atria from the ventricles and playing a part in contraction of the papillary muscles.
In endochondral ossification, some say "bone chases cartilage." What does this mean?
The cartilage model grows, then breaks down and is replaced by bone.
Why is Willie Nelson so wrinkly at his older age? What are the factors that contribute to this?
The dermis of the skin breaks down or gets thinner. Also, elastin starts breaking down as well when you get older. Sun exposure or activities such as smoking could speed up this process.
What happens in eccentric contraction?
The muscle generates force as it lengthens (occur in calf muscles when walking up a steep hill). Are about 50% more forceful than concentric contractions at the same load
What is the length/tension curve?
The ideal length-tension relationship occurs when a muscle is slightly stretched and the thin and thick filaments overlap optimally (generates maximum force when it's between 80% and 120% of its optimal resting length), because this relationship permits sliding along nearly the entire length of the thin filaments. If you stretch a muscle severely, it cannot develop tension because the myosin heads have nothing to attach to. Likewise, at a lower percent of resting length, its ability to generate force (or shorten) is limited because the actin myofilaments in its sarcomeres overlap and the thick filaments run into the Z discs, restricting further shortening.
What is the length/tension curve? Explain in regards to sarcomeres. What is MOST critical in this graph?
The ideal length-tension relationship occurs when a muscle is slightly stretched and the thin and thick filaments overlap optimally (generates maximum force when it's between 80% and 120% of its optimal resting length), because this relationship permits sliding along nearly the entire length of the thin filaments. If you stretch a muscle severely, it cannot develop tension because the myosin heads have nothing to attach to. Likewise, at a lower percent of resting length, its ability to generate force (or shorten) is limited because the actin myofilaments in its sarcomeres overlap and the thick filaments run into the Z discs, restricting further shortening.
What is the Bundle of His?
The next stop; the only electrical connection between the atria and ventricles. Has right and left bundles.
Describe the function of muscle tissue.
The only tissue that shortens upon mechanical, physical, or chemical stimulation. Skeletal, cardiac, and smooth muscle.
What does the plateau region of the length-tension curve correlate to?
The plateau region is due to the bare zone of the myosin (bare zone=where there are no heads on the thick filament (myosin)). So the plateau is just about in the region of optimal tension (80-120%) where the actin can range in the amount of overlapping in the bare zone since it won't necessarily affect it to a certain extent.
Define sarcomere.
The structural/functional unit of muscle defined as "Z-line to Z-line"
Why are capillaries important to muscles?
They accommodate changes in muscle length. they straighten when the muscle stretches and contort when the muscle contracts. They provide oxygen and nutrients to muscles.
What does this degradation do to the area in regards in inflammation and calcium deposition?
This degradation increases the imflammation and casues hyaline cartilage to calcify
What is the function of troponin?
Troponin is attached to the protein tropomyosin and lies within the groove between actin filaments in muscle tissue. In a relaxed muscle, tropomyosin blocks the attachment site for the myosin crossbridge, thus preventing contraction.
T/F. ATP is required to release the myosin head from the actin binding site.
True
Which muscle fiber type is more phasic and which is more tonic?
Type 1 fiber = more tonic Type 2 and IIb = more phasic
Describe the differences between Type I, Type IIa, and Type IIb muscle fibers in relation to diffusion distance, capillary numbers, ability to react to repeated stimulation.
Type 1- thin, high, slow Type IIa- medium, intermediate, fast Type IIb- thick, low, fast look at the chart on the index card
Define wave summation
When two identical stimuli are delivered to a muscle in a rapid succession, the second twitch will be stronger than the first and appear to ride on the shoulders of the first. Occurs because the second contraction occurs before the muscle has completely relaxed; muscle is already partially contracted so there will be even more shortening than the first.
How are myosin ATPase and velocity of shortening correlated? Be able to explain.
With larger amounts of ATPase (to turn ATP into ADP and Phosphate (Pi)) and myosin, the velocity of muscle shortening will increase. This is because when ATP is hydrolyzed by ATPase, it provides the energy for the myosin head to form a cross bridge, and as the ADP and Pi are released, the myosin head bends and pulls the actin filament in towards the M line thus contracting or shortening the muscle. So, with more hydrolysis of ATP and more myosin, the velocity (distance/time) of shortening will increase.
What is the difference between yellow and red marrow?
Yellow → fat Red → blood
Does the number of fat cells change throughout lifespan? Does the size of fat cells change throughout lifespan?
Yes, last trimester, first 2 years of life and adolescence, but after that they don't Yes they can grow and shrink
If you are deficient in Vitamin D and calcium, how does this affect bones?
Your body must have vitamin D to absorb calcium and promote bone growth. Too little vitamin D results in soft bones in children (rickets) and fragile, misshapen bones in adults (osteomalacia).
What is a motor unit?
a motor neuron and all the muscle fibers it innervates
Which proteins allow for muscle contraction?
actin and myosin
Using proper anatomical terms, the coracoid process is ___________ to the Acromion?
anterior
The product of this sweat gland includes protein & lipid substances that become odoriferous as a result of bacterial action
apocrine gland
What factors influence the stability of synovial joints?
articular surfaces accessory structures muscles ligaments joint capsule
Two types of friction reducing structures are:
bursae- fluid filled sac, provides cushioning tendon sheaths
What signal is used by the muscle cell to elicit a muscle contraction?
calcium
An example of a saddle joint can be found in which anatomical structure?
carpometacarpal joint of the thumb
What is ATPase?
catalyzes the decomposition of ATP into ADP and a free phosphate ion
Vessels _________ during contraction phase and ________ during relaxation phase.
compress open
What determines the size of lamellae?
diffusion distance of the blood vessels
What is another name for the cuticle?
eponychium
Scar tissue is a type of ________________ tissue.
fibrous
In the force-velocity curve, what is the relationship between the velocity and the force generated by a muscle?
greater load - slower velocity
Explain the force/velocity curve
greater load = less speed less load = greater speed
What is the benefit to having bursae and tendon sheaths between bony protuberances?
it reduces the friction between bones and wear and tear
Explain a first class lever
load--fulcrum--lever Advantage--strength Disadvantage--speed and distance i.e. head and neck
What are the four types of bones, and which one of the four are commonly found in the hands/feet?
long--in hands and feet short flat irregular
What is the white part at the base of the nail called?
lunule
Why is the downside of using osteoprogenitor cells for regeneration of tissue?
may increase the risk of cancer
Pennation loses 13% of muscle force, what advantage does pennation give to offset this loss?
more muscle fibers, greater maximum force and speed
What is the size principle?
motor units are recruited from smallest to largest
Where does tropomyosin reside?
on the thin filament in the sarcomere; Actin
What is a unique characteristic of first degree burns?
only the epidermis is damaged, symptoms include redness, swelling, and pain, they tend to heal in 2 to 3 days without special attention, sunburn is an example
What are the two types of Arthritis? Which one is the most common? Which one is an autoimmune disorder?
osteoarthritis - most common rheumatoid arthritis - autoimmune disorder
What is the functional unit of bone called?
osteon or Haversian system
When a stem cell differentiates to become bone it is called ________________.
osteoprogenitor
What is steric hindrance?
physical blocking of two proteins from interacting (example: troponin and tropomyosin vs. myosin)
What do the smallest motor unit cell bodies typically innervate?
slow twitch muscle fibers (Type I)
What is an osteon?
the structural unit of compact bone, interconnecting canals, also called the Haversian system
What is a triad?
structure formed by a T tubule with a sarcoplasmic reticulum (Terminal cisternae on either side)
What is the function of collagen with bone?
structure, elasticity, and tensile strength to resist stretch and twistings
Describe how the integumentary system can cool the body?
sweating and evaporation of sweat
What is the space between the neuromuscular junction and the sarcoplasmic reticulum called?
synaptic cleft
What is the difference between amphiarthrosis and synarthrosis?
synarthrosis- immovable joints amphiarthrosis- slightly movable joints
What are the four main components of the shoulder joint?
tendon sheath bursa cartilaginous socket articular cartilage
Inflammation occurring at tendon sheaths is called _______ and is typically caused by ________?
tendonitis overuse
What is the basic unit of compact bone?
the osteon- elongated cylinder oriented parallel to the long axis of the bone functionally osteons are tiny weight bearing pillars
What is the difference between a skeletal muscle fiber and a skeletal muscle cell?
they are the same thing
What gland is responsible for controlling bone growth/degradation rates?
thyroid gland
Filament actin within a sarcomere looks like what?
two strands of pearls twisted in a helical fashion
What are the fast fatigue-resistant motor units?
type IIa - fast oxidative fibers
Can you tie a chicken bone in a knot? If not, why? If so, why and how? How does this relate to lecture?
yes, you can because the vinegar breaks down the hydroxyapatite in the bone allowing it to be flexible, leaving only the collagen
What is optimal power?
⅓ max velocity
