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a&p 2 test1
Question | Answer |
---|---|
SNS | operates under conscience control, seldom affects long-term servival, controls skeletal muscles |
ANS | operates without conscious instruction, controls visceral effectors, coordinates system function |
symptoms of sympathetic division | Heightened mental alertness, Increased metabolic rate, Reduced digestive and, urinary function, Energy reserves activated Increased respiratory rate and respiratory passageways dilate, Increased heart rate and blood pressure, Sweat glands activated |
symptoms of the parasympathetic division | Decreased metabolic rate, Decreased heart rate and blood pressure, Increased secretion by salivary and digestive glands, Increased motility and blood flow in digestive tract, Urination and defecation stimulation |
what fibers are related with the sympathetic division | Preganglionic fibers (thoracic and superior lumbar; thoracolumbar) synapse in ganglia near spinal cord, Preganglionic fibers are short, Postganglionic fibers are long |
what fibers are related with the parasympathetic division | Preganglionic fibers originate in brain stem and sacral segments of spinal cord; craniosacral, Synapse in ganglia close to (or within) target organs, Preganglionic fibers are long, Postganglionic fibers are short |
what are the ganglia that are located in the sympathetic nervous system | Sympathetic chain ganglia, Collateral ganglia, Suprarenal medullae |
sympathetic chain ganglia | are on both sides of the vertebral column, on preganglionic fiber synapses on many ganglionic neurons,post ganglionic fibers control visceral effectors in body wall, head, neck, limbs and innervate the sweat glands and smooth muscles in blood vessels |
each sympathetic chain ganglia contains what? | 3 cervial ganglia, 10-12 thoracic ganglia, 4-5 lumbar ganglia, 4-5 sacral ganglia, and 1 coccygeal ganglia |
collateral ganglia | are anterior to vertebral bodies and contain ganglionic neurons that innervate tissue organs in the abdominopelvic cavity |
splanich nerves | Formed by preganglionic fibers that innervate collateral ganglia, In dorsal wall of abdominal cavity, Originate as paired ganglia (left and right), Usually fuse together in adults |
postganglionic fibers in the collateral ganglia | Leave collateral ganglia, Extend throughout abdominopelvic cavity, Innervate variety of visceral tissues and organs |
preganglionic fibers in the collateral ganglia | from seven inferior thoracic segments, End at celiac ganglion or superior mesenteric ganglion, fibers from lumbar segments end at inferior mesenteric ganglion |
celiac ganglion | Pair of interconnected masses of gray matter , May form single mass or many interwoven masses, Postganglionic fibers innervate stomach, liver, gallbladder, pancreas, and spleen |
superior mesenteric ganglion | Near base of superior mesenteric artery, Postganglionic fibers innervate small intestine and proximal 2/3 of large intestine |
inferior mesenteric ganglion | Near base of inferior mesenteric artery, Postganglionic fibers provide sympathetic innervation to portions of: Large intestine , Kidney , Urinary bladder , Sex organs |
adrenal medullae | very short axons, when stimulated release neurotransmitters into blood stream, function as hormones to affect target cells throughout the body and the effects last longer |
stimulation of sympathetic preganglionic neurons | Releases ACh at synapses with ganglionic neurons , Excitatory effect on ganglionic neurons |
ganglionic neurons | Release neurotransmitters at specific target organs,telodendria form sympathetic varicosities that resemble string of pearls |
andrenergic neurons | axon terminals that release NE at most varicosities |
cholinergic neurons | ganglionic neurons release ACh instead and are located in the body wall, skin, brain, and smooth muscles |
what are alpha receptors and were are they located | alpha 1 and alpha 2 and are located IN the plasma membrane |
alpha 1 | More common type of alpha receptor, Releases intracellular calcium ions from reserves in endoplasmic reticulum, Has excitatory effect on target cell |
alpha 2 | Lowers cAMP levels in cytoplasm, Has inhibitory effect on the cell, Helps coordinate sympathetic and parasympathetic activities |
what are the beta receptors and were are they located | beta 1, beta 2 and beta 3; located ON the plasma membrane; Affect membranes in many organs (skeletal muscles, lungs, heart, and liver), Trigger metabolic changes in target cell, Stimulation increases intracellular, cAMP levels |
beta 1 | increases metabolic activity |
beta 2 | triggers relaxation of smooth muscles along respiratory tract |
beta 3 | leads to lipolysis, the breakdown of triglycerides in adipocytes |
sympathetic stimulatoin and release of NE and E | Primarily from interactions of NE and E with two types of adrenergic membrane receptors; Alpha receptors (NE more potent) and Beta receptors, Activates enzymes on inside of cell membrane via G proteins |
sympathetic stimulation and release of ACh and NO | cholinergic (ACh) sympathetic terminals and nitroxidergic synapses |
cholinergic sympathetic terminals | Innervate sweat glands of skin and blood vessels of skeletal muscles and brain, Stimulate sweat gland secretion and dilate blood vessels |
nitroxidergic synapses | Release nitric oxide (NO) as neurotransmitter, Neurons innervate smooth muscles in walls of blood vessels in skeletal muscles and the brain, Produce vasodilation and increased blood flow |
autonomic nuclei | Are contained in the mesencephalon, pons, and medulla oblongata; Associated with cranial nerves III, VII, IX, X; In lateral gray horns of spinal segments S2–S4 |
what are the ganglia associated with the parasympathetic division | terminal ganglia, and intramural ganglia |
terminal ganglia | near target organ, usually paired |
intramural ganglion | embedded in tissues of target organ, interconnected masses, and clusters og ganglion cells |
parasympathetic nuerotransmitter | all parasympathetic neuromuscluar junctions release ACh as a neurotransmitter |
what are the two parasympathetic receptors | nicotinic receptors and muscarinic receptors |
nicotinic receptors | On surfaces of ganglion cells (sympathetic and parasympathetic), Exposure to ACh causes excitation of ganglionic neuron or muscle fiber |
muscarinic receptors | At cholinergic neuromuscular or neuroglandular junctions (parasympathetic), At few cholinergic junctions (sympathetic), G proteins, Effects are longer lasting than nicotinic receptors, Can be excitatory or inhibitory |
dual innervation: sympathetic division | widespread impact, reaches organs and tissues throughout tbody |
dual innervation: parasympathetic division | innervates only specifi visceral structures |
dual innervation in both | most vital organs recieve instructions from both divisions, two divisions commonly have opposing effects |
anatomy of dual innervation | Parasympathetic postganglionic fibers accompany cranial nerves to peripheral destinations; Sympathetic innervation reaches same structures by traveling directly from superior cervical ganglia of sympathetic chain |
autonomic tone | Is an important aspect of ANS function, If nerve is inactive under normal conditions, can only increase activity, If nerve maintains background level of activity, can increase or decrease activity |
heart recieving dual innervation with the parasympathetic division | Acetylcholine released by postganglionic fibers slows heart rate |
heart recieving dual innervation with the sympathetic division | NE released by varicosities accelerates heart rate |
heart recieving dual innervation with both division | Autonomic tone is present, Releases small amounts of both neurotransmitters continuously |
visceral refelxes | Provide automatic motor responses, Can be modified, facilitated, or inhibited by higher centers, especially hypothalamus |
visceral reflex arc | Receptor, Sensory neuron, Processing center (one or more interneurons), All polysynaptic, Two visceral motor neurons |
three characteristics of higher order functions | Require the cerebral cortex, Involve conscious and unconscious information processing, Are not part of programmed “wiring” of brain , Can adjust over time |
fact memories | are specific bits of info |
skilled memories | Learned motor behaviors, Incorporated at unconscious level with repetition, Programmed behaviors stored in appropriate area of brain stem, Complex are stored and involve motor patterns in the basal nuclei, cerebral cortex, and cerebellum |
short term memories | information that can be reflected immediatly, contain small bits of information, primary memories |
long term memories | Memory consolidation – conversion from short-term to long-term memory; Two types of long-term memory; Secondary memories fade and require effort to recall, Tertiary memories are with you for life |
memory engram | single circuit responses to single memory, forms as result of experience and repitions |
state of consciousness: deep sleep | Also called slow-wave or Non-REM (NREM) sleep, Entire body relaxes, Cerebral cortex activity minimal, Heart rate, blood pressure, respiratory rate, and energy utilization decline up to 30% |
REM sleep | Active dreaming occurs, Changes in blood pressure and respiratory rate, Less receptive to outside stimuli than in deep sleep, Muscle tone decreases markedly, Intense inhibition of somatic motor neurons, Eyes move rapidly as dream events unfold |
huntingtons disease | Destruction of ACh-secreting and GABA-secreting neurons in basal nuclei, Symptoms appear as basal nuclei and frontal lobes slowly degenerate, Difficulty controlling movements, Intellectual abilities gradually decline |
lysergic acid diethylamide (LSD) | Powerful hallucinogenic drug, Activates serotonin receptors in brain stem, hypothalamus, and limbic system |
parkinsons disease | Inadequate dopamine production causes motor problems |
dopamine | Secretion stimulated by amphetamines, or “speed”, Large doses can produce symptoms resembling schizophrenia, Important in nuclei that control intentional movements, Important in other centers of diencephalon and cerebrum |
effects of aging | Anatomical and physiological changes begin after maturity (age 30), Accumulate over time, 85% of people over age 65 have changes in mental performance and CNS function |
endocrine communications | release chemicals (hormones) into bloodstream, alters metabolic activities of many tissues and organs simultaneously |
synaptic communication | ideal for crisis managment, occurs across synaptic clefts, chemical message is neurotransmitter, limited to very specific area |
hormones | stimulate synthesis of enzymes or structural proteins, increase or decrease rate of synthesis, turn existing enzyme or membrane channel on or off |
three classes of hormones | amino acid derivatives, peptide hormones, and lipid derivatives |
amino acid derivatives | small molecules structurally related to amino acids; derivatives of tyrosine: thyroid hormones, catecholamines (E, NE, and dopamine), derivatives of tryptophan (serotonin and melatonin) |
peptide hormones | are chains of amino acids,glycoprotiens, short chain polypoetides, small protiens |
glycoprotiens | Proteins are more than 200 amino acids long and have carbohydrate side chains (Thyroid-stimulating hormone (TSH), Luteinizing hormone (LH), Follicle-stimulating hormone (FSH)) |
short chain polypetides | Antidiuretic hormone (ADH) and oxytocin (OXT) (each 9 amino acids long) |
small protiens | Growth hormone (GH; 191 amino acids) and prolactin (PRL; 198 amino acids) |
lipid derivatives | eicosanoids:derived from arachidonic acis a 20 carbon fatty acid and steriod hormones derived from cholestrol |
eicosanoids | Paracrine factors that coordinate cellular activities and affect enzymatic processes in extracellular fluids , Some eicosanoids have secondary roles as hormones |
a second group of eicosanoids | second group of eicosanoids - prostaglandins - involved primarily in coordinating local cellular activities, In some tissues, prostaglandins are converted to thromboxanes and prostacyclins, which also have strong paracrine effects |
steroid hormones | Released by reproductive organs, The cortex of the adrenal glands, The kidneys, Because circulating steroid hormones are bound to specific transport proteins in the plasma:remain in circulation longer than secreted peptide hormones |
free hormones | remain functional for less than one hour |
thyroid and steriod hormones | remain in circulation much longer because most are bound |
catecholamines and peptide hoemones | are not lipid soluble, unable to penetrate plasma membrane, bind to receptor protiens at outer surface of plasma membrane |
eicosanoids | are lipid soluble, diffuse across plasma membrane of reach receptor protiens on inner surface of plasma emebrane |
first and second messengers | Bind to receptors in plasma membrane, Cannot have direct effect on activities inside target cell, Use intracellular intermediary to exert effects |
first messenger | Leads to second messenger, May act as enzyme activator, inhibitor, or cofactor , Results in change in rates of metabolic reactions |
important second messenger | Cyclic-AMP (cAMP) Derivative of ATP, Cyclic-GMP (cGMP) Derivative of GTP, Calcium ions |
down regulation | Presence of a hormone triggers decrease in number of hormone receptors, When levels of particular hormone are high, cells become less sensitive to it |
up regulation | Absence of a hormone triggers increase in number of hormone receptors, When levels of particular hormone are low, cells become more sensitive to it |