Muscle/skeletal/Respitory
Terms
undefined, object
copy deck
- What is smooth muscle responsible for
- Gi motility, constriction of blood vessels, uterine contractions
- Which portions of the nervous system controll each type of muscle
-
Cardiac/smooth=autonomic
Skeletal: somatic - How do skeletal muscles initial movement
- they are connected on each side to different bones through tendons composed of collagen.
- Describe the difference between the origin and the insertion
-
origin: muscle bone attachment near the center of the body usually stays in place
insertion: farther joint - What type of neurotransmitter is used at neuromuscular junctions
- acetylcholine
- What is an antagonistic muscle and what is a synergistic muscle
-
Antagonistic is a movement in both directions Bis/tris
Synergistic is one way. - What is a fascile
- the muscle tissue,and connective tissue bundles which allow for muscle flexibility
- What is another name for muscle fibers
- myofibers which are single muscle cells
- Muscle cells have?
- multinucleated syncytia formed by fusion of individual cells durring development. Invervated by a single nerve ending that stretches the length of the muscle.
- what is the plasma membrane of muscle cells called and why is it special
- sarcolemma. has plasma membran and additional layer of polysaccharide and collagen which helps cells fuse with the tendon
- What are myofibrils
- a small unit within a muscle cell that is responsible for the striated appearance that generate contraction.
- What are the thin/thick filaments composed of?
-
thin:actin
thick: myosin - What denotes the boundry of sarcomeres
- the two z lines, this is where actin filimants attach myosing does not attach here.
- Describe the sliding filament model and how it works.
- The thick fillaments hydrolyze atp ant its head and where myosin is attached to the actin in a cross bridge. This shortens the gaps between z lines.
- Diagram the steps of a contractile cycle
-
1. binding of myosin head to myosin binding site(cross bridge)
2. power stroke: myosin head pulls the actin chain(ADP is released)
3. Binding of new ATP molecule causes release of actin by myosin
4. ATP hydrolysis occurs and cocks the head. - what does the troponin/tropomyosin complex do?
-
troponin: globular protein that binds Ca and undergoes a conformational change.
Tropomyosin: long fibrous protein which winds around thick filaments and blocks myosin binding sites. Regulates muscle contractions - What is special about the neuromuscular junction
- it is the synapse between muscle and an axon terminus. It is elongated so it can depolarize a large area. motor end plate is myofiber at junction and it uses Ach
- What is end plate potential
- It is the depolarization of the postsynaptic membrane due to AcH opening Na+ receptors. 1 vesicle causes minature EPP
- What is the function of acetylcholinesterase
- It hydrolyzes AcH to choline and an acetly unit. Stops muscle flexing
- What is the function of the transverse tubules(t-tubule)
- An action potential needs to depolarize the entire myofiber to flex the muscle. Aps tend to stay near the membrane surface of the thick cells so these deep infoldings aid in this process
- What is the function of the sarcoplasmic reticulium
- it sequesters(active transport) Ca when an action potential is not achieved and releases it into the sarcoplasm when depolarization occurs(Voltage gated Ca channels)
- What are the two ways to incres the force of contraction
-
by motor unit recruitment. activating more than one neuron.
Frequency summation where there are fast depolarizations and the contraction builds on itself - What is tetanus and what is the disease tetnus
- A rapidly repeating series of stimulations that builds on the first. Tetnus is a bacterial toxin that moves through the neuron and causes depolarization and strong contractions
- What molecule regenerates ATP in muscle quickly
- creatine phosphate
- What is the function of myoglobin
- it stores O2 for the mitochondria of the muscle tissue
- What happens when the muscle runs out of 02 in a long contraction
- it uses the lactic acid cycle and ph drops. it is transported to the liver where it makes pyruvate
- What is the cause of rigor mortis
- it is the stiffening of muscles due to ATP exhaustion
- What are the similarities of cardiac muscle to skeletal muscle
-
Striated(sarcomers)
Presence of T tubules
Troponin/tropomyosin
Length-tension relationship= optimum length for great force - How does cardiac muscle differ from skeletal muscle
-
No syncytial(one nucleus)(has functional synctium because of intercalated disks which allow ion passage
Connection to other cells by intercollated disks
Contraction not dependant on motor neurons
Uses Voltage gatedNAKchannels - What are the inhibitory/exititory nerves of the cardiac tissue
- The vagus(parasympathetic) releases ach and inhibits the heart contractions at the SA node. SA node stimulates contraction
- Describe the cardiac action potential diagram
- Rapid depolarization due to fast Na+ channels. Plateau phase due to Na+/Ca++ channels. Repolarization due to K+ channels
- What is the significance of the plateau phase
- longer duration of contraction(emptying of ventricles) Long refractory period to prevent disorganization of transmission impulses(tetanus/summation impossible)
- How are smooth muscle and skeletal muscle similar
- Respond to Ca++ use sliding of actin/myosin
- How are smooth and skeletal muscle different
-
One nucleus:connected by gap junctions(functional synctia)
Action potential varies depending on location of the cell.
No sarcomeres(smooth)
Shorter and narrower
No T tubules
Sar Reticulum not important
No troponin/tropomyosin
Autonomic motor response - What is used instead of troponin in the smooth muscles
- calmodulin and myosin light chain kinase. Calmodulin activats MLCK and myosin is phosphorylated.
- What type of ion channels do smooth muscles use
- slow na+ channels(10-20 times longer to get depolarization)can have slow wave with spikes in gut
- What stimulates the heart muscle
- NE from sympathetic nervous system
- what is the difference in innervation between smooth and skeletal muscles
- both motor. skeletal somatic and can only innervate one cell. smooth autonomic and can innervate multiple cells because of gap junctions
- What are the 5 roles of the skeleton
-
Support the body
provide a framework for movement
Protect vital organs
Store Ca++
Hematopoiesis(red,white,platelet formation) - What is the difference between the axial and appendicular components of the endoskeleton
-
axial: skull, vertebral column, rib cage
appendicular: all the rest - What are connective tissues and what is the progenetor cell
- cells and material they secrete. Fibroblasts: secrete collagen and extracellular elastin. adipocytes, chondrocytes, osteocytes
- Describe loose connective tissue
-
Loose: adipose and material inbetween cells(extracellular matrix. composed of proteoglycans(protein core and glucosaminoglycans) hydrophylic
Basement membrane(collagen that seperates epithelial from connective tissue - Describe the dense connective tissue
- bones, tendons, ligaments
- Describe flat bone
- scapula, ribs, skull: location of hematopoiesis and protect organs.
- Describe long bones
-
Bones of limbs: movement have 2 epiphysis(shell of compact with core of spongy)
Diaphysis(tube of contact bone with yellow marrow) - What is bone marrow and where is it found
-
Spongy material:
yellow: in shafts of long bones inactive and fatty
red: within spongy pores of flat bones: site of erythropoiesis - What are the two principle ingredients of bones
- collagen and hydroxyapatite(material consisting of calcium phosphate crystals) Collagen ordered and other stuff around it
- What does spongy bone look like
- very dissordered and has spikes of trabeculae
- What does the compact bone look like
-
functional units of Haversian stystem or osteon.
Central haversian canal with blood, lymph vessels and nerves. rings called lamellae. Canaliculi to lacunae or osteocyte. Connected by gap junctions. - What are volkmans canals
- channels that run perp to haversian canals to connect osteons
- What cells produce cartlige and what are the three types
- chondrocytes hyaline, elastic, fibrous
- hyaline cartilage
- Strong and flexible: larynx, trachea, articular cartilage of bone joints
- Elastic cartilage
- ear, epiglottis more flexible contains elastin
- Fibrous cartilage
- Rigind and strong. pelvis(pubic symphysis) and invertebral disks of spinal column.
- Why do cartilage injuries take a long time to heal
- low metabolic rate because of low blood flow
- Describe the growth of bones
- The epiphyseal plate between diaphysis and epiphysis have cartilage growing between them which causes elongation and replaced by bone. Stimulated by growth hormone and stopped by androgens and estrogen at puberty
- Describe bone remodeling
-
degradation and synthesis of bone. osteoblasts lay down collagen and hydroxyapatite.
Osteoclasts dissolve the hydroxyapatite crystals like macrophage. lacuna is space where osteobast is inside bone. Osteoclasts cause incres in serum ca++/phosphate - What is the function of calcitonin
- increase osteoblast activity decreases osteoclasts and decreases renal/intestinal Ca++ absorption
- What does calcitriol do
-
From Vit D
Decreseas osteoblast activity in creases osteoclasts. incresease Ca++ absorption - What Does parathyriod hormone do
- increses osteoclasts, decrease blasts, incres renal absorption of Ca++
- What do ligaments do
- Connect bones to other bones
- What do tendons do
- connect bones to tendons
- What are synarthroses
- sites where bones fuse together(immovable joints)
- What are amphiarthroses
- slightly moovable joints like vertibrae
- What are diarthroses
- movable joints like ball and socked and hinges
- What is the synovial fluid
- the fluid in the capsule that lubricates joints.
- What is the articular cartlage
- the surface between two connecting bones that is easily damaged and causes arthritis and stiffness
- What are the tasks performed by the respitory system
-
Gas exchange
pH regulation
Thermoregulation(heat loss due to breathing)
Protection from disease and particulate matter - What does hyperventilation do to the blood
- Reduces CO2 which reducus carbonic acid which raises the pH
- What does hypoventilation do
- makes the blood more acidic
- What is the path of inhaled air?
- nose-nasopharynx-pharynx-larynx-trachea-bronchi-bronchioles-aveolar ducts-alveoli
- What are the functions of the larynx
-
Made of cartilage so airway will remain open.
Contains the epiglotis which seals the tracea durring swallowing to prevent entry of food.
contains the vocal cords - What are bronchiles composed of
- smooth muscle and contain no cartilage. 1mm wide and allows for the regulation of the diameter to adjust air flow
- Describe the alveoli
- Tiny thin transparent sacks at the end of bronchioles that are 1 cell thick except where capillaries cross. Site of gas exchange
- What is known as the conduction zone of the respitory system
- the entire respitory tract down to the bronchioles. All tall columnar epithelial cells that dont allow gas exchange
- What do goblet cells do
- secrete specialized layer of sticky mucus
- What is the function of the cillia in the columnar zone
- They constantly force mucus twords the pharynx which can be swallowed or coughed out. Gets rid of pathagons and particles. Mucociliary escalator
- What are the components of the respitory zone
- The alveoli, alveolar ducts, and small bronchioles. All involed in gas exchange
- What type of cells are found in the respitory zone
- small epithelial simple squamous cells. Single layer.
- What is the role of alveolar macrophages
- mucus would retard gas exchange so these cells aid in disease prevention
- What is the function of surfactant
- It is a soapy substance that coats the alveoli and reduces surface tension which would cause alveolar collapse due to water cohesion. made from phospholipids, protein, and ions secreted by fat cuboidal cells which are metabolically active
- How does inspiration occur
- by contracting the diaphragm which enlarges the chest cavity
- What drives expiration
- the elastic recoil of the lungs which requires no muscle contraction
- What would happen if the lungs were taken out of the chest cavity
- they would collapse
- What two structures line the chest cavity
-
parietal pleura: lines the chest cavity
Visceral pleura: lines the lungs - What is the pleural space
- the narrow cavity between the two pleura. There is a negative pressure(vacuum) in this space so the membranes are drawn together. There is also fluid thatkeeps them together by surface tension
- Describe the structure of the diaphragm
- It is a skeletal muscle below the ribs between the abdomen and the chest cavity.It is shaped like a dome and when it contracts it flattens and draws the chest cavity to expand along with the intercostal muscles to allow for inspiration
- What does the abdominal muscle do when experation occurs
- it forces the diaphragm uppwords and further shrinks the lungs durring exertion
- Describe the steps of inspiration
-
Diaphragm expands
volume of the chest cavity expands
pleural pressure decreases becoming more negative.
the lungs expand
the pressure in the alveoli becomes negative
Air enters the lungs/alveoli - When is the alveolar pressure exactly zero
- at the endo of resting expiration and just after inspiration
- What would be the result of a holein the lungs that allowed inhaled air to flow into the pleural cavity
- Air would flow into the cavity causing the lungs to collapse. inspiration would be impossible due to the lack of negative pressure
- What is spirometry
- the measurement of the volume of air enterning the lung at various stages of respiration
- What is Tidal volume
- the amout of air that enters and exits the lungs during normal breathing is about 10% of the lung volume
- What is the expiratory reserve volume
- volume of air that can be epired after passive resting expiration
- What is the inspiratory reserve volume
- Volume that can be inspired after the relaxed inspiration
- Inspiratory capacity
- is the maximal volume of air which can be inhaled after resting expiration
- Residual volume
- the amount of air that remains in the lungs after the strongest possible expiration
- Vital capacity
- the maximal amout of air that can be forced out of the lungs after the deepest possible breath
- What is the total lung capacity
- the vital capacity and the residual volume added together
- What is pulmonary edema
- an increased blood pressure in the lungs that causes fluid to enter the lungs. Due to left atrium pressure increase. Usually prevented by lympocytes.
- What can result from a high pulmonary capillary hydrostatic pressure
-
accumulation of interstitial fluid in the lungs
Fluid accumulation in the alveoli
Decreased oxygenation of the blood due to excess fluid and slowing 02 diffusion - What structures act as the respitory membrane
- O2/CO2 has to diffuse across the alveolar epithelium, through the interstitial liquid and across the capillary endothelium. Lipid bilayers do not inhibit this flow
- What drives oxygen into the alveolar capillaries
- the oxygen pressure gradient between the alveolar air and the the oxygen in the blood
- Why is the atmospheric P02 higher than the arterial P02
- ph20 and pco2 are higher in the alveoli so the po2 must decrease
- What has a higher oxygen affininty hb or myoglobin
- myoglobin
- What portion of the brain controls the involuntary process of breathing
- the respitory control center in the medulla of the brain stem
- What three chemical stimuli regulate respiration
- PCo2 pH and po2 finally
- How is breathing regulated
-
peripheral chemorecpetors in the aortic and carotid arteries.
Medullary respitory control center chemoreptors in the cns - What does the parasympathetic nervous system do to the lungs
- it releases ACh into the smooth muscle of the large bronchioles. This is in response to irritation of the lung and prevents the irritation to spread.
- What does epinepherine do in the lungs
- it increses the ventilation and causes airway smooth muscles to relax.
- What does asthma do and what do inhalers contain
- Spasm in the airway smooth muscles. Inhalers contain epinephrine, antihistamines, and anticholinergics.
- What happens in the lungs in response to a high pCo2
- peripheral chemireceptors and medullary respiration control center receptors respond. Increased Co2 causes decrease in pH and this is what is sensed respitory rate increased
- What happens in response to a low pH in the blood
- increased respitory rate due to peripherial chemoreceptors and medullary respiratory center
- What happens in response to a stretching of the lung
- stretch receptors in the lung inhibit respiration
- What happens in response to chemical irritation
- irritation receptors of the lung start coughing or bronchoconstriction
- What is the largest organ in the body by size and weight
- the skin
- What is the roll of the skin
- to protect from pathogens, excess evaporation of water, and to regulate body temperature.
- Diagram the layers of the skin
- epidermis dermis subcutaneous tissue or hypodermis which is composed of fat an insulating layer
- What is the epidermis composed of
- a stratified(many layers) of squamous epithelial cells. which are constantly degredade and replenished by mitosis from the stratum basale(deep part of epidermis)
- What happens when the epidermal cells die
- they are keratinized and surrounded by keratin which helps in skin water proofing
- What is the function of melanin
- it is a pigment that is produced by specialized cells in the epidermis(melanocytes) which help absorb the uv light of the sun to prevent tissue damage
- Does the epidermis have blood vessels
- nope
- What are teh functions of the dermis sensory receptors
- convey info about touch, pressure, pain, itch, and tickle to the cns
- Where are the sudoriferous glands found
- sweat glands are in the dermis
- Where are the sebaceous glands found
- oil glands are in the dermis
- Where are hair follicles found and what are hairs composed of
- dermis and they are composed of tightly bound epithelial cells that are dead.
- Describe a sudoriferous gland
- it is a structure that origionates in the dermis and leads through the epidermis via a pore on the skin surface. It allows loss of excess heat by evaporation
- What is the effect of aldosterone on sweat composition
- it causes the conservation of ions in high heat environments. so sweat has less salt
- What is chemical thermogenesis or non shivering thermogenesis
- the process of creating heat from brown fat tissue
- What does the thyroid hormone do
- increases temperature due to an increased metabolic rate it takes several weeks
- How is day to day temperature regulated
- contraction of skeletal muscles by shivering or moving. Skin insulates so heat is conserved. Constriction of dermis blood vessels minimizes heat loss in response to sympathetic nervous system pale skin.
- What causes dissipation of excess heat
- evaporation due to sweating and dilation of blood vessels.