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193 Cards in this Set
- Front
- Back
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What is Superior?
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Toward the head, upper, above.
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What is Inferior?
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Toward the feet, lower, below.
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What is Anterior?
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In front of, the front, ventral for humans.
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What is Posterior?
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In back of, the back, dorsal for humans.
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What is Medial?
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Towards the mid-line of the body.
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What is Lateral?
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Towards the side of the body, away from the mid-line.
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What is Proximal?
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Toward or nearest the trunk of the body or nearest the origin point.
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What is Distal?
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Away or farthest from the trunk or point of origin.
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What is Superficial?
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Nearer to the surface.
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What is Deep?
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Farther away from the body surface.
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What does ATP stand for and what does it do?
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Adenosine Triphosphate. Energy for anabolism and various biological processes.
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What is the fluid mosaic model?
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Primary structure of a cell membrane is a double layer of phospholipid molecules. Heads are hydrophilic and tails are hydrophobic. The bilayer is hydrophobic so it doesn't allow water or water-soluble molecules through.
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What is the function of the cell membrane?
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It controls what moves through any section by proteins embedded in the phospholipid bilayer. Proteins are like gates only allowing specific molecules through. Glycoprotein molecules on the surface as as flags/markers/antigens.
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Which two ways do substances move through cell membranes?
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By concentration gradients (when substances flow from one concentration to another) or dynamic equilibrium (when molecules on either side move continuously but at a constant rate.)
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What are passive processes?
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They do not require any energy expenditure (breakdown of ATP.)
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What are the four passive transport processes?
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Simple diffusion, osmosis, channel-mediated passive transport, carrier-mediated passive transport.
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What is simple diffusion?
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Movement of particles through the phospholipid bilayer or through channels from an area of high concentration to an area of low concentration (down the concentration gradient.)
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What is osmosis?
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Diffusion of particles through a selectively permeable membrane in the presence of at least one impermeant solute (usually involves simple and channel-mediated diffusion)
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What is channel-mediated passive transport?
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Diffusion of particles through a membrane by means of channel structures in the membrane (particles move down their concentration gradient.)
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What is carrier-mediated passive transport?
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Diffusion of particles through a membrane by means of carrier structures in the membrane (particles move down the concentration gradient.)
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What are the results of osmosis?
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The gain of volume on one side of the membrane and the loss of volume on the other side.
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What is an isotonic solution?
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Two fluids with the same osmotic pressure.
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What is a hypotonic solution?
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When the osmotic pressure is lower than that of another solution. A cell in a hypotonic solution expand and burst due to the inward diffusion of water.
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What is a hypertonic solution?
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When the osmotic pressure is higher than that of another solution. A cell in a hypertonic solution will shrivel as it loses pressure and volume as water moves out of the cell into the hypertonic solution.
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What are active processes?
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Processes that require energy from metabolic processes.
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What are the four active transport processes?
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Pumping, phagocytosis (endocytosis), pinocytosis (endcytosis), exocytosis.
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What is pumping?
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Moving of solute particles from an area of low concentration to an area of high concentration (up gradient) by means of an energy-consuming pump structure in the membrane.
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What is phagocytosis?
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Movement of cells or other large particles into cell by trapping it in a section of plasma membrane that pinches off to form an intracellular vesicle.
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What is pinocytosis?
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Movement of fluid and dissolved molecules into a cell by trapping them in a section of plasma membrane that pinches off to form an intracellular vesicle. Only very small particles or liquid.
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What is exocytosis?
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Movement of proteins or other cell products out of the cell by fusing a secretory vesicle with the plasma membrane.
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What are enzymes?
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Functional proteins which lower activation energy required to start metabolic pathways. Most enzymes are specific in their action and only act on a specific substrate.
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What is cellular respiration?
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The process by which a cell breaks down glucose or any nutrient that has been transformed into glucose.
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How does cellular respiration produce energy?
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The molecule breaks down and potential energy is released by being transferred to the high energy bonds of ATP. ADP floating around and add a phosphate from the bond to create ATP.
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What are the three stages or cellular respiration?
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Glycolysis (anaerobic, occurs in cytosol, creates 2 ATP) Citric Acid Cycle (aerobic, occurs in mitochondria) Electron Transport System (aerobic, occurs in mitochondria's fold) 34 ATP created between Citric and Electron.
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What are the four ways water leaves the body?
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As urine through the kidneys, as water expired through the lungs, as sweat through the skin and as feces from the intestine.
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What is the most abundant and widely distributed type of body tissue?
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Connective tissue.
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What are the functions of connective tissue?
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Supports, connects, transports and defends.
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What are the two principal divisions of the nervous system?
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The Central Nervous System (CNS) and the Peripheral Nervous System (PNS).
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What is the CNS and what does it do?
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It's the structural and functional center of the nervous system. Consists of the brain and spinal cord. Integrates sensory information, evaluates it and initiates an outgoing response.
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What is the PNS and what does it do?
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It's nerves that lie in outer regions of the nervous system. Includes cranial nerves (originate from the brain) and spinal nerves (originate from the spine.)
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What is the afferent division?
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All incoming sensory pathways.
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What is the efferent division?
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All outgoing motor pathways.
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What is the Somatic Nervous System (SNS)?
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The voluntary division of the nervous system. Two sub-divisions; somatic motor division (carries info to the somatic effectors (skeletal muscles)) and the somatic sensory division (carries feedback info to the somatic integration centers in the CNS.)
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What is the Automatic Nervous System (ANS)?
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The involuntary division of the nervous system. Contains two sub-division; Sympathetic division (prepares the body to deal with immediate threats to the internal environment, fight or flight response) Parasympathetic division (coordinates the body's normal resting activities, rest & repair division.)
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What are membrane potentials?
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A slight excess of positively charged ions on the outside of the membrane and slight deficiency of positively charged ions on the inside of the membrane. The difference in electrical charge is called potential because it's a type of stored energy.
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What is a polarized membrane?
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A membrane that exhibits a membrane potential.
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What is the unit of measurement used to depict the magnitude of potential difference between two sides of a polarized membrane?
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Volts (V) or millivolts (mV). The sign of the voltage indicates the charge on the INSIDE surface of a polarized membrane.
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What is Resting Membrane Potential (RMP)?
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Membrane potential maintained by a nonconducting neuron's plasma membrane, typically -70mV.
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What is Action Potential?
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Membrane potential of a neuron that is conducting an impulse. Also known as nerve impulse. It's an all or none response.
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Why does the action potential never move backward?
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As a consequence of the refractory period.
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What are the six regions of the brain?
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Frontal lobe, Parietal lobe, Occipital lobe, Temporal lobe, Cerebellum and Brain Stem.
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What does the speed of the nerve conduction depend on and why does it matter?
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It depends on the diameter of the nerve fiber and the presence or absence of a myelin sheath. The larger the nerve fiber the faster it conducts. A mylein sheath allows the conduction to hop along where as the absence requires the conduction to slide along in a continuous wave.
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What is the Absolute Refractory Period?
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A brief period lasting half a millisecond during which a local area of a neuron's membrane resists restimulation and will not respond to a stimulus no matter how strong.
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What is the Relative Refractory Period?
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Time during which the membrane is repolarized and is restoring the resting membrane potential, a few milliseconds after the ARP, and it will only respond to a very strong stimulus.
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What is the mechanism of a synaptic transmission?
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Action potential reaches a synaptic knob>causes calcium ions to diffuse into the knob rapidly>increased calcium triggers the release of neurotransmitter via exocytosis>neurotransmitter molecules diffuse across the synaptic cleft and bind to receptor molecules>ion channels open.
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What is Cerebrospinal Fluid (CSF)?
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Supportive cushioning fluid. Resevoir of circulating fluid that combined with blood, the brain monitors for changes in internal environment. Normally sterile, clear, colorless. Contains same elements as blood but in lower concentrations.
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What fluid spaces contain CSF?
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The subarachnoid space around the brain and spinal cord adn within the cavities of the brain and spinal cord.
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What is the cycle of CSF?
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Formed by separation of fluid from blood in the choroid plexuses into the ventrical of the brain. It circulates the ventricles and into the central canal and subarachnoid spaces and then is absorbed back into blood.
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What does the brainstem consist of?
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Medulla oblongata (lowest), pons (middle) and midbrain (uppermost). The brainstem conducts impulses to the higher parts of the brain, motor tracts conduct from the higher part of the brain to the spinal cord.
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What are three centers located in the medulla oblongata?
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The cardiac center, vasomotor center and respiratory center.
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What does the cardiac center of the medulla do?
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Controls heart rate. Has both inhibitory and acceleratory fibers. The inhibitory impulses chronically run to the heart via the vagus nerve to instruct the heart to slow down its rate.
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What does the vasomotor center of the medulla do?
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It's responsible for sending impulses through the spinal cord to the spinal nerves directly to the walls of the muscles surrounding the arteries and causing arterial constriction to elevate arterial blood pressure when needed.
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What does the respiratory center of the medulla do?
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Controls the rate and depth of breathing. Functions in unison with the respiratory nuclei of the pons (which regulates rhythmic breathing)
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What are some of the other functions of the nuclei within the medulla?
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Reflex functions such as sneezing, coughing, vomiting, swallowing. These functions are either involuntary or start out voluntary and become involuntary.
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What are the functions of the cerebellum?
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Conscious planning and co-ordination. Acts with cerebral cortex to produce skilled movements through groups of muscles. Controls posture; functions below the level of consciousness to make movements smooth, steady, efficient, coordinated. Controls skeletal muscles for balance. Coordinates incoming sensory info and acts to assist the cerebrum.
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What are the two hemispheres and what do they do?
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Left (logical and controls motor of right side) and Right (creative and controls motor of left side.)
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What are chemoreceptors?
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Receptors activated by amount or changing concentration of certain chemicals (eg. taste and smell)
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What are thermoreceptors?
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Receptors activated by changes in temperature.
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What are nociceptors?
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Receptors activated by intense stimuli that may damage tissue. Produces pain sensation.
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What are osmoreceptors?
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Receptors activated by changes in concentration of electrolytes in extracellular fluids. Concentrated in the hypothalamus.
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What two types of nerve fibers carry pain impulses from the nociceptors?
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Acute fibers (A) that mediate sharp, intense, localized pain. Chronic fibers (B) that mediate less intense but more persistent, dull or aching pain.
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What are the special senses?
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Receptors grouped closely together or grouped in specialized organs, eg. smell, taste, hearing, equilibrium, vision.
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Why do we have Pupillary Responses and what do they do?
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We need to control the amount of light entering our eye because under too strong light intensity our retina may be damaged and under low light intensity we need more light to form a brighter image.
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What muscles control pupillary responses?
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The antagonistic muscles of the iris. It's done by reflex mechanisms meaning it's an involuntary, automatic response.
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Why do our cells have unique cell markers?
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To identify the cells as ones belonging to ourselves as individuals so that immune system cells do not self-attack.
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What do foreign cells have?
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They have non-self molecules that serves as recognition markers for our immune system.
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What is self-tolerance?
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The ability for our immune system to attack abnormal or foreign cells but spare our own normal cells.
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What are the two types of immune mechanisms and what do they do?
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Innate immunity and adaptive immunity. Innate is in place before a person is exposed to a specific harmful particle or condition Adaptive is in place after a threat is received from a foreign cell. The mechanism responds by targeting the activity of these agents and these agents only.
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What are the four signs of inflammation?
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Redness, heat, swelling and pain.
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What are B cells?
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Antibody-mediated immunity, produce antibodies that attack pathogens.
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What are T cells?
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Cell-mediated immunity, attach pathogens directly.
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What are effector cells?
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B or T cells that actively produces an immune response such as secreting antibodies (effector B) or directly attacking other cells (effector T).
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What are memory cells?
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B or T cells that has been activated by is not an effector cell producing an active response, survives a long time in lymph nodes and if later exposed to the same antigen, forms a clone of cells that rapidly produce a specific immune response.
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What are the stages of an adaptive response?
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Recognition of antigen > activation of lymphocytes (B or T cells) > effector phase (immune attack) > decline of antigen causes lymphocyte death (homeostatic balance) > memory cells remain for later response if needed.
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What are the formed elements of blood?
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Red Blood Cells (RBC/erythrocyte)
White Blood Cells (WBC/leukocytes) Platelets (thrombocytes) |
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Describe plasma.
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Clear, straw-colored fluid that consists of 90% water, 10% solutes.
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What is Hematocrit or Packed Cell Volume?
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Volume percent of red blood cells in whole blood depicted by centrifuge separation. WBC & platelets less than 1%. Loss of blood volume would be indicated by a high hematocrit value.
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What is the function of RBCs?
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Playing a critical role in the transport of oxygen and carbon dioxide in the body which depends on hemoglobin.
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What is leukopenia?
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Decrease in the number of WBCs.
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What is leukocytosis?
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Increase in the number of WBCs.
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What are the functions of platelets?
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Play important role in hemostasis and blood clotting. Hemostasis refers to the stoppage of blood flow and may occur as the end result of a body defense mechanism.
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What happens within 1 to 5 seconds after injury to a blood capillary?
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Platelets adhere to the damaged lining and to each other to form a hemostatic platelet plug which helps stop the flow of blood into the tissues. Occurs after vascular spasm.
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What is vascular spasm and what does it do?
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It's caused by the constriction of smooth muscle fibers in the walls of the damaged blood vessels. It can cause temporary closure of a damaged vessel and lessen blood loss until the platelet plug and subsequent coagulation effectively stop the hemorrhage.
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How does the platelet plug form?
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Platelets undergo a change in response to an encounter damaged wall or tissues. Sticky platelets are created and bind to underlying tissue and each other. They secrete chemicals that affect blood flow and platelet aggregation at the injury site.
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What are two conditions that hasten clotting?
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A rough spot on the endothelium or abnormally slow blood flow.
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What is responsible for the production of the proteins required for the clotting process?
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The liver. If the liver is unable to produce these proteins it could result in excessive bleeding.
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What happens to blood in the veins in a case of ischemia or hemorrhage?
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The blood is quickly moved out of blood reservoirs and shifted to arteries that supply the heart and the skeletal muscles.
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What is a venous pump?
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Blood pumping action of respirations and skeletal muscle contractions facilitate venous return by increasing pressure gradient between peripheral veins and vena cava.
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How do respirations increase the pressure gradient?
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They increase the pressure gradient between peripheral veins and central veins by decreasing central venous pressure and also by increasing peripheral venous pressure.
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How do skeletal muscle increase the pressure gradient?
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By promoting venous return by squeezing veins through a contracting muscle and milking the blood toward the heart.
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What do the semilunar valves do?
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Prevent backflow.
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What are the coverings of the heart?
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Fibrous Pericardium and Serous Pericardium.
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Describe the fibrous pericardium and it's function.
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Tough, loose-fitting and inelastic sac around the heart. Provides protection against friction as it is smooth and well lubricated.
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Describe the serous pericardium and it's function.
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Two layers, parietal (lining inside the fibrous) visceral (epicardium, adheres to outside of heart) Between the layers is the pericardial space filled with pericardial fluid. Produces lubrication to protect the heart.
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Explain blood flow from the head and neck or the lower body.
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Head/neck empties into the superior vena cava and blood from the lower body empties into the inferior vena cava, both end up in the right atrium then > through tricuspid valve > right ventricle > pulmonary semilunar valve > pulmonary trunk > right and left pulmonary arteries > lung tissue for gas exchange > pulmonary veins > left atrium.
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Explain blood flow from lungs.
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After being brought from the body, through the heart to the lungs for gas exchange, the blood is emptied into the left atrium (O2 rich) > mitral valve > left ventricle > aortic semilunar valve > aorta > body (except lungs)
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What are the four structures of the conduction system of the heart and what are they?
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Sinoatrial (SA) Node, Atrioventricular (AV) Node, AV bundle, Purkinje System. They are all modified cardiac muscle. They are not contractile and permit only generation or rapid conduction of an action potential through the heart.
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Where does the normal cardiac impulse initiate?
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The sinoatrial node (SA), called the pacemaker of the heart. The cells of the SA possess an intrinsic rhythm at regular intervals without needing signals from the brain or cord. Under resting conditions, rhythmical rate of 70-75 beats per min.
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What does the p wave of an ECG represent?
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The spread of electrical activity over the atrium. Depolarization begins at the sinoatrial (SA) node near the top of the atrium.
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What happens during the PR segment?
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Not seen on ECG it's as the electrical wave moves slowly through the atrioventricular (AV) node
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What happens during the QRS segment of the EGG?
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The QRS complex represents activation of the ventricle. Special conducting bundles spread the wave of depolarization rapidly over the ventricle.
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What happens during the ST segment of the ECG?
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The ST segment is the portion falling between the QRS complex and the T wave. The ventricle is contracting, but no electricity is flowing.
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What happens during the T wave?
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The T wave represents the wave of repolarization, as the ventricle prepares to fire again.
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What is happening during atrial systole?
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Contracting force of atria completes emptying of blood from the atria to the ventricles, AV valves are open, ventricles are relaxed and filling with blood, SL valves are closed, begins with P wave of ECG, after polarization, atrial musculature contracts.
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What is Isovolumetric Ventricular Contraction?
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Refers to having the same measured volume. This occurs during the start of ventricular systole and opening of semilunar valves when ventricular volume remains constant and pressure increases rapidly, Coincides with R wave of ECG and first heart sound.
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What is Ejection?
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Semilunar valves open and blood is ejected from the heart when pressure gradient in ventricles exceeds pressure of pulmonary artery and aorta. Rapid ejection marked by increase in ventricular and aortic pressure/blood flow. Reduced ejection appears later and has a less abrupt decrease in ventricular volume. T wave on ECG.
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What are the heart sounds and what is physiologically happening?
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Lub occurs due to the contraction of the ventricles and vibrations of the closing AV valves. Dub is caused by closing of the SL valves.
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What are the functions of the respiratory system?
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Air distribution and gas exchange. Supplying oxygen and removing carbon dioxide from cells.
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What does the cribform plate do?
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Separates roof of nose from cranial cavity, holes permit branches of olfactory nerve to enter cranial cavity
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What does the septum do?
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Separates nasal cavity into left and right cavities
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What does the nose do?
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It's the passageway for air to and from lungs, filters air, aids in speech and makes it possible to smell.
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What are the functions of the larynx?
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Respiration, vocalization, swallowing.
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What are the primary gas exchange structures?
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Alveoli.
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What is the respiratory membrane?
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The barrier between alveolar air and blood across which gases are exchanged.
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What are the differences between the left and right lungs?
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Right is bigger with 3 lobes, 3 secondary bronchi, 2 fissures, 10 segments. Left is smaller with concavity for the heart. 2 lobes, 3 secondary bronchi, 1 fissure, 8 segments.
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What is the pathway followed to get air from the atmosphere into the lungs?
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Air enters the nostrils > passes through the nasopharynx > oropharynx > through the glottis >
into the trachea > into the right and left bronchi, which branches and re-branches into bronchioles, each of which terminates in a cluster of alveoli |
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What does the thorax do?
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Functions to bring about inspiration and expiration.
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What is respiratory physiology?
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Complex coordinated processes that help maintain homeostasis.
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What is external respiration?
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Pulmonary ventilation (breathing) and pulmonary gas exchange in the capillaries of the lungs.
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What is internal respiration?
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Systemic tissue gas exchange and cellular respiration.
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What are the two components of the respiratory cycle?
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Inspiration (moves air into the lungs) and expiration (moves air out of the lungs)
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What is the primary principle of ventilation?
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Establishment of two gas pressure gradients. One where the alveoli pressure is lower than that of the atmosphere to produce inspiration and one where the alveoli pressure is greater than that of the atmosphere to produce expiration. When the pressure is equal, there is no air entering or leaving the lungs.
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What is boyle's law?
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The volume of gas varies inversely with the pressure at a constant temperature.
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What physiologically happens during inspiration?
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The diaphragm contracts, moving downward, the intercostals move the anterior of each rib up and out, sternum elevates and enlarges thorax from front to back and side to side. This leads to decreased Pip and Palv and results in inspiration.
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What physiologically happens during expiration?
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The diaphragm relaxes (by a passive process), moving up into the thoracic cavity, the ribs contract down on the lungs, expelling the remaining air. This leads to increases Pip and Palv and results in expiration.
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What is quiet inspiration?
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Contraction of the diaphragm alone or contraction of the diaphragm along with the external intercostal muscles.
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What is forced inspiration?
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Uses the muscles from quiet inspiration and receives aid from the sternocleidomastoid, pectoralis minor, serratus' and abdominals to aid in the elevation of the sternum and rib cage.
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What is transpulmonary pressure?
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The negative intrapleural pressure obtained from the difference between Pip and Palv. Pressure between parietal and visceral pleura is less than alveolar pressure and less than atmospheric pressure which creates a vacuum to prevent the lungs from collapsing in on themselves.
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When do accessory respiratory muscles function?
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They do not function during normal ventilation but may be needed in some respiratory disorders, they are only used during forced breathing (exercise, asthma) May become part of normal breathing pattern if a disorder exists.
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What is a pneumothorax?
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When air enters the pleural cavity (space between chest wall and lungs) either from the outside or inside. The lung collapses and makes it mechanically impossible to breathe, the RV is eliminated.
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What is Dalton's law?
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The partial pressure of a gas in a mixture of gases is directly related to the concentration of that gas in the mixture and to the total pressure of the mixture.
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Where does the exchange of gases take place in the lungs?
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Between the alveolar air and blood flowing through lung capillaries (all over the respiratory membrane.)
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How do gases move through the respiratory membrane?
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O2 enters the blood from alveolar air because PO2 of AA is greater than PO2 of incoming blood (down gradient). CO2 will flow down gradient from blood into AA as PCO2 of venous blood is higher than that of AA.
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What are the four factors that determine the amount of oxygen that diffuses into blood?
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GRADIENT: O2 pressure gradient between AA and incoming pulmonary blood. SURFACE AREA: total functional SA of the respiratory membrane. VOLUME: respiratory minute volume. VENTILATION: Alveolar Ventilation.
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What are the four structural factors that facilitate oxygen diffusion from AA to blood?
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THIN: walls of the alveoli and capillaries for gases to cross. LARGE: alveolar and capillary surfaces. LARGE: lung capillaries have a large amount of blood THIN: blood is distributed through capillaries in a thin layer so each RBC comes close to AA.
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Explain O2 transport?
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Two forms; dissolved in plasma and associated with hemoglobin. To combine with hemoglobin, O2 must diffuse from plasma into RBCs. Increasing blood PO2 accelerates hemoglobin association. Normal saturation is 97%
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Explain CO2 transport?
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Small amount dissolves in plasma and transported as solute this produces blood PCO2. 20% combines with NH2 and other proteins to form carbaminohemoglobin. 70% is carried as bicarbonate ions in plasma. Arterial PCO2 is 35-40 mm Hg, venous is 46 mm Hg. Increased CO2 causes decrease in blood pH (more acidic.)
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Explain gas exchange at the tissue level?
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takes place between arterial blood flowing through tissue capillaries and cells. O2 diffuses out of blood because O2 gradient prefers outward diffusion (down gradient to lower level in cells/tissues) as O2 diffuses out, blood PO2 decreases which accelerates dissociation to release more O2 to plasma for diffusion to cells.
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What is Hypoxia?
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When body or region of the body is deprived of adequate oxygen supply. Produces lactic acid, can lead to cell death. May respond with vasodilation to allow greater perfusion.
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What is Anoxia?
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Hypoxia with complete deprivation of oxygen.
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What is bohr effect?
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Increased PCO2 decreases the affinity between O2 and hemoglobin. By the time the blood hemoglobin returns to the alveoli the hemoglobin is saturated by CO2 and the alveoli are O2 saturated.
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What influence does the ANS have on respirations?
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SNS increases the diameter of the airways and increases the respiration rate. PNS decreases diameter of airways and decreases respiration rate.
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What are the three types of levers?
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First Class : LFP
Second Class: FLP Third Class: FPL |
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What is the general function of muscle?
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Movement of the body as a whole or in parts, heat production and posture.
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What are the characteristics of muscle?
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Excitability (ability to be stimulated)
Contractility (ability to contract/shorten to produce body movement) Extensibility (ability to extend/stretch allowing muscles to return to their resting length) |
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What are the four types of proteins that make up myofilaments?
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Myosin, actin, tropomyosin, troponin.
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What is myosin?
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Makes up most of the thick filament, myosin heads attracted to actin molecules, known as cross-bridges when attached to actin.
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What is actin?
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Globular protein that forms two fibrous strands that twist around each other to form bulk of thin filament.
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What is tropomyosin?
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Protein that blocks active sites on actin molecules.
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What is troponin?
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Protein that holds tropomyosin molecules in place.
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What is the mechanism of contraction?
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Muscle fiber is stimulated from rest at by a motor neuron at a neuromuscular junction (where sarcolemma is connected at endplate) > acetylcholine is released into the synaptic cleft diffuses across gap, stimulates receptors and initiates impulse into sarcolemma > impulse travels over sarcolemma and inward along t tubes which trigger release of Ca++ ions, Ca++ binds to troponin causing tropomyosin to shift and expose active sites on actin then the sliding filament model takes over.
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What is the sliding filament model?
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When active sites on actin are exposed myosin heads bind to them. Myosin heads bend pulling the thin filaments past them. Each head releases, binds to next active site and pulls again.
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What's a twitch contraction?
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Quick jerk of muscles produced as a result of a single brief threshold stimulus. Latent phase (nerve impulse travels to SR to trigger release of Ca++) Contraction phase (Ca++ bind to troponin and sliding filaments occurs) Relaxation phase (sliding filaments ceases)
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What is Treppe?
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Staircase phenomenon, gradual step-like increase in strength of contractions seen in a series of twich contractions. Eventually muscles responds with less forceful contractions and relaxation phase becomes shorter. When disappears, a contracture occurs.
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What is tetanus?
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Smooth, sustained contractions, multiple wave summation is multiple twitch waves added together to sustain muscle tension for a longer time. Incomplete tetanus is very short relaxation between peaks, complete tetanus is when the twitch waves fuse into a single sustained peak.
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What is a tonic contraction?
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Continual, partial contraction of a muscle.
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Muscles with less tone are?
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Flaccid.
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Muscles with more tone are?
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Spastic.
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Muscle tone is maintained by?
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Negative feedback mechanisms.
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What is the graded strength principle?
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Skeletal muscles contract with varying degrees of strength at different times. Contributed by metabolic condition of fibers, number of muscle fibers contracting simultaneously, number of motor units recruited.
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What is isotonic contraction?
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Contraction in which tone or tension remains the same as the length of the muscle changes.
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What is isometric contraction?
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Contraction in which tension increase but muscle length stays the same.
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What does concentric mean?
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Muscle shortens as it contracts.
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What does eccentric mean?
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Muscle lengthens while contracting.
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What are immovable joints?
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Synarthroses or bony. Fit together closely allowing little or no movement.
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What are slightly movable joints?
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Amphiarthroses or fibrous/cartilagenous.
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What are freely movable joints?
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Diarthroses or synovial.
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What are the types of motion permitted in joints?
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Monoaxial, biaxial, triaxial.
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What are gliding movements?
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Simplest of all movements, articular surface of one bone moves over articular surface of another without any angular or circular movement.
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What are angular movements?
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Change the size of the angle between articulating bones (flexion, extension, hyperextenstion, plantar flexion, dorsiflexion, adduction and abduction.)
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What are circular movements?
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Rotation, circumduction, supination, pronation.
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What is flexion?
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decreases angle between bones, bends or folds one part on another.
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What is extension and hyperextension?
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Extension (increases angle between bones, returns a part from it's flexed position to anatomical position) Hyperextension (stretching or extending part beyond its anatomical position)
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What is plantar flexion and dorsiflexion?
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Plantar (increases angle between top of foot and front of leg) Dorsiflexion (decreases angle between top of foot and front of leg.)
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What is abduction and adduction?
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Abduction (moves a part away from median plane of body) Adduction (moves a part towards median plane of body)
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What is rotation and circumduction?
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Rotation (pivoting a bone on its own axis) Circumduction (moves a part so that its distal end moves in a circle)
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What is supination and pronation?
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Supination (turns the hand palm side up) Pronation (turns the hand palm side down.) Can be left or right, medial (internal) or lateral (external).
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Describe Uniaxial joints.
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Synovial joints that permit movement around only one axis and only in one plane (hinge and pivot.)
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Describe Biaxial joints.
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Synovial joints that permit movements around two perpendicular axes in two perpendicular planes. (saddle and condyloid)
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Describe Multiaxial joints.
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Synovial joints that permit movements around three or more axes in three or more planes. (ball and socket, gliding)
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What are the four types of bone cells?
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Osteocytes (mature bone cells, in lacunae, connected by canaliculi) Osteoblasts (synthesize new matrix, osteogenesis) Osteoclasts (dissolve bone matrix, osteolysis) Osteoprgenitor (differentiate into osteoblasts)
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What are the types of bone marrow and their function?
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Red Marrow (found in virtually all bones in infant/child, functions to produce red blood cells, in adults ribs, vertebrae, humerus, pelvis, femur) Yellow Marrow (replaces red marrow when cells become saturated with fat and are no longer active in blood cells, when needed can be converted back to red)
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What are the three types of cartilage?
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Hyaline (most common, covers articulating surfaces of bones, costal cartilages, trachea, bronchi of lungs) Elastic (external ear, epiglottis, eustachian tubes, elasticity and resiliency) Fibrocartilage (symphis pubis, intervertebral disks, strong and rigid)
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