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A and P Oral Exam
n/a
143
Agriculture
Undergraduate 3
05/09/2010

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Term
Negative Feedback
Definition
End process has negative impact (opposite result) on process.
Example: Decrease blood to the brain-stimulation of the heart-increased blood to brain-increase blood pumped
Term
Positive Feedback
Definition
End-product feeds back to increase its own production-can be dangerous
Example: giving birth (cycles increase until animal is born)
Term
Positive Feedforward
Definition
reaction feeds forward (feeds on itself)
Example: Tear in blood vessel, clotting factor 1, clotting factor 2, etc...
Term
Hyperplasia
Definition
Increase in number of cells
Term
Hypertrophy
Definition
Increase in size of cells
Term
Epithelim
Definition
makes up the skin, outer surface of the body
Term
Cell Membrane
Definition
the selectively permeable outer membrane of the cell that is composed of a lipid bylayer, and cholesterol
Term
Nucleus
Definition
the part of the cell body that contains DNA adn aids in several body functions
Term
Endoplasmic Reticulum
Definition
a system of channels within the cell that run from the nucleus to the exterior cell membrane
Term
Golgi
Definition
an organelle located near the nucleus that is shapted like sacs that are stacked and flattened at the ends. It is believed to be involved in the synthesis of proteins and enzymes
Term
Mitochondrion
Definition
the primary sources of ATP formation for aerobic cell respiration
Term
Facilitated Diffusion
Definition
the diffusion of molecules across the cell membrane with the aid of carrier proteins and also requires a concentration gradient. This reaction is otherwise unable to be performed as simple diffusion, and it requires no energy or ATP. Examples would be amino acids and glucose
Term
Simple Diffusion
Definition
The ability of some melecules, such as water, oxygen and CO2 to pass through the cell membrane without the additional aid of carrier proteins. Particles move with the concentration gradient.
Term
Active Transport
Definition
the proces that moves ions or molecules across the cell membrane and against the conentration gradient; requires energy (usually in the form of ATP) and a protein carrier
Term
Phagocytosis and Pinocytosis
Definition
cell engulfs a particle that is too large for diffusion
cell enguls liquid "fat"
Term
Osmosis and water movement
Definition
movement of WATER from low particle (high water) concentration to high particle (low water) concentration. Diffusing from an area of more water and less particles to an area of lower water and more particles.
Water will move from hypotonic (less particles) to hypertonic (more particles)
Term
Radiation
Definition
Heat energy transmitted as rays to surrounding areas-no direect contact or medium for transfer
Term
Conduction
Definition
heat energy passes by direct contract through a nonmoving medium-example is animal lying on a concrete floor-result in rapid heat loss, dependint on temperature difference
Term
Convection
Definition
like conduction, except medium is moving-animals standing in cold wind or in water-the medium is moving and the heat is transferred away form teh animal and causes much more rapid heat loss
Term
Evaporation
Definition
heat is transferred through the conversion of liquids on the skin to water vapor-mechanism of heat loss during sweating or panting-rates are increased by convection
Term
Epiderms
Definition
outermost layer of the skin-consists of cells that are no longer living-is insensensitive and has no direct blood supply
Term
Dermis
Definition
contains nerves, blood vessels and the root of the hair follicle
Term
Eccrine and Apocrine Sweat Glands
Definition
produce salty sweat, involved in temperature regulation
Term
Eccrine and Apocrine Sweat Glands
Definition
produce salty sweat, involved in temperature regulation
Term
Dermis
Definition
contains nerves, blood vessels and the root of the hair follicle
Term
Hair shaft=cortex, medulla, and cuticle
Definition
Cortex is generally the largest of these
Medulla may be absent
Cuticle is usually affected by conditioers
Term
Laminitis
Definition
may be severe enough to cause rotation of the coffin bone through the sole of the hoof. Too much carbohydrate in the diet for digestion-produces lactic acid bacteria-endotoxins are absorbed and reduce ciculation in the extremities
Term
Osteocytes
Definition
Mature bone cell. Located in the spaces in the ossified matrix called lacunae
Term
Osteoblasts
Definition
The cells that produce bone. They develop from cartilage cells and mature into bone-producing cells
Term
Osteoclasts
Definition
cells of the bone that absorb bone and structures adn reshape remodel damaged bone. Bone destroying cells.
Term
Epiphyseal plate
Definition
the growth plate of a long bone. Epiphyseal plates are located at the junction of the proximal and distal epiphyses with the diaphysis. They are areas where long bones increase in length by teh process of endochondral bone formation. When an animal reaches its full size, the epiphyseal plate of its bones completely ossify and the bones cease their growth
Term
Chondrocyte
Definition
mature cartilage cells
Term
Osteoid
Definition
layer of bone matrix (osteiod) primarily consisting of collagen
Term
Hydroxyapatite
Definition
inorganic matrix-composed of crystalline salt made up of calcium and phosphate
Term
Parathyroid hormone (PTH)
Definition
the hormone secreted by the parathyroid gland that prevents the level of calcium in the blood from getting too low
Term
Vitamin D
Definition
a fat-soluable vitamin essential for life in most organisms. Vitamin D enables the body to use calcium and phosphorus and is necessary for the formation of healthy bones and teeth. Enhances Ca2+ uptake in the gut and opposes the effects of PTH. Increases blood Ca+.
Term
Calcitonin
Definition
the hormone secreted by the thyroid gland that prevents the level of calcium in teh blood from getting to high. Stimulates a decrease in blood Ca2 and increases PTH release which is much more powerful than calcitonin
Term
Central Nervous System (CNS)
Definition
the brain and spinal cord. Processes information and sends and receives information
Term
Somatic nervous system-Peripheal Nervous System (PNS)
Definition
transmits all information from environment to central nervous system
Term
Symathetic nervous system-Peripheal Nervous System (PNS)
Definition
Fibers leave teh spinal cord throught all thoracic and 1st one or two lumbar vertebrae. Most important regarding ciculation.
Term
Fight or flight response
Definition
a whole body response resulting from an animal feeling threatened that prepares the body for intense physical activity. It results from a comnination of direct sympathetic nerve stimulation and the release of epinephrine and noepinephrine into the bloodstream from the adrenal gland. Effect in the body include increased heart rate and output, increased blood pressure, dilated air passageways in the lungs and decreased gastrointestinal function
Term
Epinephrine
Definition
commonly called adrenaline. A hormone secreted by the medulla of the adrenal gland under stimulation by the sympathetic portion of the autonomic nervous system. It produces part of the fight-or-flight response that results when an animal feels threatened
Term
Norepinephrine
Definition
A hormone secreted by the medulla of the adrenal gland under stimulation by the sympathetic portion of the autonomic nervous system. It produces the fight-or-flight response when an animal feels threatened.
Term
Sympathomimetics
Definition
Drugs which mimic the effect of the sympathetic nervouse system (epinephrine)
Term
Parasympathetic nervous system
Definition
part of the automonic nervous system that is responsible for the "rest-and-restore" response. Arises from cranial nerves 3, 4, 5, and 6 and sacral spinal nerves
Term
Parasympathomimetics
Definition
Drugs that mimic the parasympathetic nervous system (acetylcholine is example). Important in vegetative functions
Term
Sympathetic tone
Definition
basal activity of the sympathetic system
Term
Parasympathetic tone
Definition
basal activity of the parasympathetic system-usually allows sympathetic to incrase or decrease organ's activity
Term
Dendrites
Definition
receives incoming messages from other nerve cells-has a starlike shape
Term
Soma
Definition
the cell body of the neuron-synthesizes neurotransmitters
Term
Axon
Definition
transmits messages outward to other cells
Term
Resting membrane potential
Definition
due to the difference in ion concentrations, there are relatively more positve ions on the outside than on the inside. Therefore it is more positive on the outside relative to the inside. The difference between the outside of the cell verses the inside. Polarized state of the membrane
Term
Sodium-potassium pump
Definition
pumps Na+ out of the cell and K+ ions into the cell-through active transport requiring a concentration gradient and energy in the form of ATP
Term
Action potential
Definition
mechanism of transmitting a nervous impulse-results from depolarizing the nerve cell membrane
Term
Depolarized membrane
Definition
membrane suddenly becomes more permeable to Na+-when the inside of the cell suddenly becomes more positive relaative to the outside due to the inflow of Na+
Term
Overshoot
Definition
when the amount of Na+ rushing into the cell causes the inside of the membrane to acutally become positive relative to the outside
Term
Repolarized membrane
Definition
the influx of Na+ is shut off-K+ suddenly allowed to rush out of the cell causing the membrane to become more positive on the outside relative to the inside.
Term
Positive afterpotential
Definition
when the amount of K+ rushing out of the cell causes the outside to become more positive than the inside due to the closing of the K+ channel (reverse overshoot)
Term
Threshold potential
Definition
stimulus greatly increases the rate at which Na+ leaks into the cell (through sodium leak channel)-membrane potential changes until Na+ channels open
Term
Refractory period
Definition
the depolarized neuron must first be repolarized before it is capable of another action potential
Term
Absolute refactory period
Definition
the point at which no amount of stimulus will initate another action potential. K+ channels are open and K+ is still rushing in, Na+ channels are in resting state
Term
Relative refactory period
Definition
Na+ channels are reset to resting state and K+ channels are still open-can have an AP but takes a large stimulus
Term
All or nothing property
Definition
an AP at one point on the membrane will cause adjacent portions to depolarize, therefore the AP is self-propagating
Term
Schwann Cell
Definition
cellular membrane that forms the myelin sheath for axons
Term
Sphingomyelin
Definition
layer after layer of lipid substance layed down by the Schwann cells
Term
Node of ranvier
Definition
unmyelinated areas of the axon between two adjacent Schwann cells that are involved in rapid conduction of nerve impulses along the axon
Term
Saltatory conductance
Definition
because nodes are the only thing that can depolarize, action potential jumps from node to node
Term
Synapse
Definition
the junction between two neurons or between a neuron and another target cell
Term
Presynaptic neuron
Definition
the neuron that is stimulated by the depolarization wave to release a neurotransmitter into the synapse
Term
Synaptic cleft
Definition
physical gap between two communicating neurons or between a neruon or between a neuron and its target cell
Term
Postsynaptic neuron
Definition
the neuron that contains the receptors to which a released neurotransmitter inds, causing depolarization or inhibition of depolarization of the neuron
Term
Exocytosis
Definition
the passage of materials too large to diffuse through the cell membrane by packaging them into vesicles, transporting them to the cell membrane, and then pressing them out of the cell
Term
Excitatory postsynpatic potential (EPSP)
Definition
chemicals released by neurons at the synapse that tend to cause excitation or depolarization of other neurons or target tissues-subthreshold potential builds up on each other until threshold potential is reached and action potential occurs-usually takes more the 1 EPSP for AP to occur
Term
Hyperpolarized
Definition
more negative on the inside relative to the outside than usual
Term
Inhibitory postsynaptic potential
Definition
chemicals released by neurons at the synapse that tend to depress or decrease depolarization of other neurons or target tissues
Term
Antagonist
Definition
prevents the neurotransmitter from binding and there blocks its effects
Term
Agonist
Definition
binds to the receptor and has similar effects as the neurotransmitter
Term
Sensory Receptors
Definition
stimuli from the external environment are detected by sensory receptors and transmitted as nervous impulses-sensation is determined by the brain and based on where fibers terminat in the brain-combination of receptors and destination in the brain determine the cause of the pain
Term
Mechanoreceptor
Definition
detect pressure on teh surface or in surrounding tissues
Term
Tactile
Definition
detect touch or pressure on body surface
Term
Deep tissue receptors
Definition
detect pressure on internal organs or tissues
Term
Hearing
Definition
sounds receptors of cochlea
Term
Thermoreceptors
Definition
temperature changes alters the permeability to ions
Term
Nociceptors
Definition
detect damage to a tissue-always result in pain impulse
Term
Electromagnetic receptors
Definition
detect light, which directly or indirectly alters receptors membrane permeability
Term
Chemoreceptors
Definition
tdetect chemical stimuli, some examples would be taste, Smell, Blood CO2, osmolality
Term
Spatial Summation
Definition
the number of receptors picking up the stimulus and transmitting it to the brain
Term
Temporal Summation
Definition
the frequency of firing of the receptors
Term
Muscle bundle
Definition
each muscles is made up thousands of these
Term
Epimysium
Definition
the entire muscle is covered by this connective tissue
Term
Perimysium
Definition
bundles of muscle fibers are covered by this connective tissue layer
Term
Muscle fiber (cell)
Definition
each muscle bundle is mad eup of thousands of these
Term
Endomysium
Definition
each muscle fiber is covered by this connective tissue layer
Term
Sarcolemma
Definition
the membrane surrounding the muscle fiber-an excitable membrane, with an electrical potential similar to nerve cells
Term
Sarcoplasm
Definition
name for the cytoplasm
Term
Myofibrils
Definition
composed of filaments of the contractile proteins actin and myosin and are packed together longitudinally in the muscle cells
Term
Sarcomere
Definition
each myofibil is composed of around 20,000 of these repeating units-consists of thick myosin and thin actin filaments
Term
Sarcoplasmic Reticulum
Definition
a specialized form of endoplasmic reticulum lies within each muscle fiber (just under the sarcolemma)
Term
Transverse tubules (T-tubules)
Definition
compose the sarcoplamsic reticulum, longitudinal tubules that parallel muscle fibers and when tubules termintae in flattened channels they are called terminal cisternae
Term
Myofilaments
Definition
made up of thick myosin and thin actin
Term
Actin
Definition
a thin protein that composes microfilaments, and are composed of two strands of actin protein which are wrapped around by tropomyosin
Term
Troponin
Definition
3rd protein in the thin filament consists of T, C and I
Term
Myosin
Definition
a thick protein that composes microfilaments
Term
H Zone
Definition
contains only thin filaments, and disappears when the muscle contracts
Term
I Band
Definition
contains only thin filaments, and shorten as the myofilaments slide over each other
Term
A band
Definition
contain both thick and thin filaments
Term
Alpha motor neuron
Definition
large, myelinated fibers which branch several hundred times and can stimulate hundreds of muscle cells
Term
Motor unit
Definition
the nerve fiber and the muscle cells that are stimulated by the alpha motor neuron
Term
Motor end plate
Definition
where the nerve fiber terminates
Term
Synaptic trough
Definition
increase surace area of the sarcolemma
Term
End plate potential
Definition
changes the resing membrane potential from as much as 50 to 75 mV-normally only 20 to 30 Mv change is required to start AP
Term
Nicotine
Definition
a poison that mimics the effets of acetycholine
Term
Isometric contraction
Definition
when the muscle contracts against a load, but does not shorten-used in posture, or any tupe of resistance to a load where movement does not occur
Term
Isotonic contraction
Definition
the muscle shortens as it contracts-involved in movement
Term
Fast fibers
Definition
Type IIa-cross between slow and fast twitch fibers-capable of using fat and sustaining contractions
Type IIb-fast twitch-use anaerobic metabolism
Term
Slow fibers
Definition
Type I-great ability to produce energy in the presence of O2-major fuel type is fatty acids from breakdown of fat
Term
Multiple motor unit summation
Definition
incresaing the number of motor nurons firing will increase the number of muscle fibers contracting
Term
Temporal Summation
Definition
the frequency of contraction becomes so rapid that the next contraction occurs before the muscle relaxes
Term
Treppe
Definition
principle of "warming up" a muscle-muscle can generate as much as 2 times the force of contraction
Term
Tetanization
Definition
no relaxation period-occurs because relaxation of the muslce is slower than contraction-can generate tremendous force
Term
Muscle tone
Definition
a certain amount of tension remains within a muscle even at rest-keeps muscles ready to respond immediatly
Term
Atropy
Definition
rate of degeneration exceeds the rate of synthesis-occurs after periods of relatively little use
Term
Muscle Denervation
Definition
a muscle must contract to maintain its size-happens almost immediatly after atropy-result of injury or disease
Term
Gap junction
Definition
provide a channel for intercellular communication
Term
Intercalated discs
Definition
connects SA node to atrial fibers and is not a barrier for flow of AP's
Term
Sinus node (SA)
Definition
controls the rate at which the heart beats-called intrinsic pacemaker and APS generated are connected directly with atrial fibers
Term
Fast opening Na+ channels
Definition
cells are naturally leaky to Na+ and once TP is reach the channels open VERY quickly-see a big spike in Na+ going into the cell
Term
Slow Ca2+ channels
Definition
slower to open and remain open much longer than Na+ channels-causese a plateau instead of a spike like skeletal muscle at the top of the AP so it is also much longer
Term
A-V node
Definition
start of the AP in ventricles is acheived by this-located in the right atrium and is connected to SA node fibers-causes delay in transmission of the AP from atria to ventricles
Term
Purkinjie fibers
Definition
transmit AP very quickly
Term
Cardiac arrythmias
Definition
abnormaly heart rythem-often caused by blockage in thransitional fibers of conductance from SA to AV node
Term
Tachycardia
Definition
fast heart rate
Term
Bradycardia
Definition
slow heart rate
Term
Ventricular escape
Definition
ventriles contracting at different rates
Term
Systole
Definition
the part of the heart cycle associated with contraction of the ventricles and atria and ejection of blood into the aterial systems
Term
Diastole
Definition
the part of the cardiac cycle associated with relaxation of the atria and ventricles and the filling of the chambers with blood
Term
P wave
Definition
depolarization of the atria-increased atrial pressure-increased ventricular volume-increased ventricular pressure
Term
QRS wave
Definition
ventricular depolarization and ventriles contracting-decreased ventricular volume-increased ventricular pressure-increased arotic pressure and atrial pressure spike due to back pressure
Term
T wave
Definition
ventricular repolarization-AV wave open soon after ventficular systole
Term
Isovolumic contraction
Definition
Term
End-diastolic volume
Definition
Term
End-systolic volume
Definition
Term
Stroke-volume output
Definition
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