HUBS 191 PROGRESS TEST 2 EXAM | QUESTIONS & ANSWERS (VERIFIED) | LATEST UPDATE | GRADED A+

1 HUBS 191 PROGRESS TEST 2 EXAM | QUESTIONS & ANSWERS (VERIFIED) | LATEST UPDATE | GRADED A+ central nervous system Correct Answer: nervous system consisting of brain and spinal cord peripheral nervous system Correct Answer: nervous system consisting of peripheral nerves glia Correct Answer: 'glue' provide support for neurons, 5 type, 4 in CNS, 1 in PNS neurons Correct Answer: nerve cells, transmission of information dendrites Correct Answer: recieve input, send info into cell body cell body 2 Correct Answer: contains nucleus and organelles axon Correct Answer: carries electrical impulses, may/may not be myelinated axon terminals Correct Answer: end terminus of the axon, neuro transmitter release tract Correct Answer: bundle of axons in the CNS grey matter Correct Answer: group of cell bodies in cerebral cortex/spinal cord white matter Correct Answer: bundle of axons in cerebral cortex/spinal cord ganglion Correct Answer: group of cell bodies in PNS nerve Correct Answer: bundle of axons in PNS 3 input zone Correct Answer: dendrites and cell body, receives chemical signals from other neurons summation zone Correct Answer: axon hillock, decides to transmit signal or not conduction zone Correct Answer: axon may be quite long, carry electrical signals between brain areas to and from spinal cord or to and from peripheral sensory receptors output zone Correct Answer: axon terminals, contact input of other neurons, release of neuro transmitter multipolar Correct Answer: multiple processes emanate from the cell body, the 'typical' neuron bipolar Correct Answer: 2 processes emanate from the cell body (axon and long bridge to dendrites unipolar 4 Correct Answer: 1 process emanates from cell body (hangs on side of axon) anaxonic Correct Answer: no distinct axon, all processes look alike astrocytes Correct Answer: supply nutrients to neuron, ensheath blood capillaries, transmit information, CNS microglia Correct Answer: immune cells of the CNS, engulf micro organisms / debris ependymal cells Correct Answer: line fluid filled spaces of brain and spinal cord, have cillia to circulate CSF, CNS oligodentrocytes Correct Answer: support nerve fibres, ensheath them with myelin, CNS schwann cells Correct Answer: support peripheral nerve fibres, ensheath them with myelin, similar to oligodendrocytes, PNS 5 myelin sheath Correct Answer: lipid wrapped around axon, increases conduction velocity, multiple schwann cells in a row form the myelin sheath, gaps between myelin called nodes of ranivier Synapse/Synpatic Cleft Correct Answer: neuro transmitter release from one axon terminals where electrical turns to chemical afferent Correct Answer: information going into the brain efferent Correct Answer: information out of brain flow of information Correct Answer: info comes through receptors, afferent nerves, into CNS, integration/coordination, motor efferent (somatic or autonomic) somatic Correct Answer: the stuff we are aware of and have control over somatic afferent 6 Correct Answer: sensory information of what we are aware of somatic efferent Correct Answer: voluntary muscle control, 2 neurons between brain and effector, upper and lower motor neuron upper motor neuron Correct Answer: cell body in brain, axon in spinal cord lower motor neuron Correct Answer: cell body in spinal cord, axon in spinal nerve neuro-muscular junction Correct Answer: Where neuron releases neurotransmitters (ACh) that depolarize muscle fiber cells -> contraction autonomic Correct Answer: involuntary control, 3 neurons between brain and effector, 2 divisions, sympathetic and parasympathetic autonomic neuron 1 Correct Answer: cell body in brain, axon in brain or spinal cord (CNS) 7 autonomic neuron 2 Correct Answer: cell body in brain or spinal cord, axon in PNS , myelinated, neurotransmitter = ACh autonomic neuron 3 Correct Answer: cell body in PNS, axon in PNS, unmyelinated, neurotransmitter = NE autonomic neurons effectors Correct Answer: smooth muscle, cardiac muscle, glands, adipose/fat tissue autonomic ganglion Correct Answer: area where synapse can occur in PNS sympathetic autonomic nervous system Correct Answer: prepares body for acute/stress response, inc. HR, blood flow, pupil size, sweating, neruon 2 axon is short, neuron 3 axon is long exit from CNS parasympathetic autonomic nervous system Correct Answer: prepares body for restful situations, opposite responses to sympathetic, neuron 2 axon long, neuron 3 axon short sympathetic chain ganglion 8 Correct Answer: where the preganglionic neurons synapse onto post ganglionic neurons resting membrane potential Correct Answer: -70mV high conc. K+ inside, high conc Na+ outside action potential Correct Answer: resting membrane - depolarzation - activation of sodium ion channels - rapid depolarization - inactivation of sodium ion channels/activation of potassium ion channels- potassium ions channels close when very hyperpolarized - both shut and pump restores voltage threshold Correct Answer: action potential must exceed axon hillock for it to be propagated, must exceed -60mV (once threshold is exceeded it will continue to depolarize to +30mV before re polarization) synaptic transmission Correct Answer: chemical binds to protein site (ACh) opening gates for protons to flow through chemically gated channels in NMJ graded depolarization 9 Correct Answer: chemical stimulus opens sodium ion channel, stimulus is removed and excess Na+ transported out of cytosol, chemical stimulus opens K+ ion channels, chemical stimulus removed foramen magnum Correct Answer: A large opening at the base of the skull through which the brain connects to the spinal cord spinal cord Correct Answer: starts at foramen magnum, finished inferior to border of first lumbar vertebra (conus medularis) inside meningeal sack which fits inside spinal cavity, filum terminale anchors spinal cord conus medularis Correct Answer: non neural cone shaped ending to the spinal cord filum terminale Correct Answer: fibrous non neural tissue tethering spinal cord to end of spinal cavity coccygeal Correct Answer: tail bone/where the filum terminale anchors spinal cord segments 10 Correct Answer: 31 segments, 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, 1 coccygeal, each has a pair of spinal nerves nerves from L1 or below must travel down to exit, called the cauda equina cauda equina Correct Answer: collection of spinal nerves below the end of the spinal cord sulcus Correct Answer: furrow fissure Correct Answer: deep sulcus direction of information Correct Answer: into CNS on dorsal aspect to spinal cord, out of CNS on ventral aspect (axons are myelinated) outwards flow Correct Answer: info leaves spinal cord through ventral roots, somatic cell bodies in ventral horn, autonomic cell bodies in lateral horn inwards flow 11 Correct Answer: cell bodies of sensory neurons in dorsal root ganglion, info comes in though dorsal roots dorsal ramus Correct Answer: efferent to back, afferent from back, somatic ventral ramus Correct Answer: efferent to front, afferent from front, somatic epineurium Correct Answer: surrounds the entire nerve nerve made of Correct Answer: fasicles and blood vessels perineurium Correct Answer: surrounds each fascicle fasicle made of Correct Answer: endoneurium covered axons 3 protective layers to the brain Correct Answer: dura mater, arachnoid mater, pia mater 12 dura mater Correct Answer: outermost layer, dense fibrous and tough, outer and inner layers, can separate to form venous sinuses, form dural folds dural folds Correct Answer: separate major divisions of brain, made by inner layer of dura mater, falx cerebri, falx cerebelli, tentorium cerebelli, provide stability of brain falx cerebri Correct Answer: separates cerebral hemispheres falx cerebelli Correct Answer: separates the two hemispheres of the cerebellum tentorium cerebelli Correct Answer: separates cerebrum from cerebellum, transverse venous sinuses Correct Answer: located where 2 layers of duramater separate, collecting veins, collect venous blood from brain and old CSF after cycled through ventricular system arachnoid mater 13 Correct Answer: layer beneath dura mater and above pia mater, spider like apperance, does not extend into sulci, contains blood vessels, ft. sub arachnoid space and arachnoid granulations subarachnoid space Correct Answer: layers/legs like pier at beach filled with cerebro spinal fluid and blood vessels, forms gel cushion arachnoid granulations Correct Answer: perforate inner layer of dura mater forming granulations, transports old CSF from sub arachnoid space into venous sinus pia mater Correct Answer: inner layer of the meninges, transparent and delicate, blood vessels and arachnoid space sit ontop of it, adheres to brain and follows gyri and extends into sulci ventricular system Correct Answer: network of interconnected spaces within brain, filled with CSF which nourishes and protects brain, lined with ependymal cells which circulate the CSF produced by choriod plexus ventricles 14 Correct Answer: 2 lateral ventricles, third ventricle, cerebral aqueduct, 4th ventricle, central canal (spinal cord) lateral ventricles Correct Answer: 2 of them, 1 in each hemisphere, in cerebrum 3rd ventricle Correct Answer: located in the diencephalon cerebral aqueducts Correct Answer: connects the third and fourth ventricles, located midbrain 4th ventricle Correct Answer: located level with cerebellum, has small holes into the sub arachnoid space cerebro spinal fluid Correct Answer: surrounds CNS, provides support and cushioning, transport nutrients and waste, produced by choroid plexus within ventrticles frontal lobe Correct Answer: motor control and language/personality 15 parietal lobe Correct Answer: somatosensory occipital lobe Correct Answer: vision temporal lobe Correct Answer: memory and hearing central sulcus Correct Answer: between frontal and parietal lobes parieto-occipital sulcus Correct Answer: between parietal and occipital lobes lateral sulcus Correct Answer: between temporal and parietal/frontal lobes transverse fissure Correct Answer: separates cerebrum from cerebellum Diencephalon Correct Answer: thalamus and hypothalamus, filled with CSF 16 brain stem Correct Answer: midbrain, pons, medulla oblongata (where sides change), connects brain to spinal cord corpus callosum Correct Answer: A thick band of axons that connects the two cerebral hemispheres and acts as a communication link between them commissural tracts Correct Answer: i.e. corpus callosum, axoms going both ways through the brain, communicating between hemispheres projection tracts Correct Answer: axons extend between cerebral cortex and other CNS areas outside cerebrum i.e. corticospinal tract association tracts Correct Answer: axons on same side within cerebral cortex, communication between brain areas, short or long distance, allows association between physical and visual primary motor cortex 17 Correct Answer: precentral gyrus, specific regions control specific regions of body, LHS brain controls RHS body, corticospinal pathway, 2 neurons primary somatosensory cortex Correct Answer: post central gyrus, specific regions receive information from specific regions within the body, 3 neuron process synapse in medulla oblongata and thalmus spinal reflexes Correct Answer: organised neural circuit, usually within spinal cord, reproducible, automatic response to stimulus, stretch and withdraw, starts in PNS voluntary movement Correct Answer: decision in frontal lobe, pre motor cortex talks to basal nuclei and cerebellum, cerebellum coordinates muscles, compares intention with result, maintains posture and gait, learns and automates movement basal nuclei Correct Answer: adjust patterns of movement and allows initiation to primary motor cortex cerebellum Correct Answer: monitors balance and eqbm, adjusts upper motor neurons movement, talks to primary motor cortex and 2 way coms to basal nuclei 18 reflex Correct Answer: information does not enter brain somatosensory senses Correct Answer: use afferent neurons, which have specialised receptor cells and turn input info into AP modality/proprioception Correct Answer: type of sensory receptor activated, nature of transduction mechanism produces modality, apply slight tension so senses changes, sensory neurons carry info to CNS intensity Correct Answer: freq of AP in afferent neuron, inc stimulus intensity will inc receptor potentials to above threshold duration Correct Answer: duration of AP firing in afferent neuron, most sensitive to change, dec output over time in response to continuous stimulation, tonic (stretch) and phasic (touch) receptors location 19 Correct Answer: location of sensory receptor, can be large or small, only afferent neurons in location affected will send information, small fields and large density give good discrimination sensory receptors Correct Answer: sense stimulus, convert to AP integration Correct Answer: cerebral cortex, concious sensation and perception sensation Correct Answer: "concious identification" of when and wehere, primary region of cortex perception Correct Answer: "meaningful interpretation", association region of cortex somatopic organisation Correct Answer: areas of cortex respond to areas of the body, densely innervated areas of body occupy large region of cortex, left cortex represents right body endocrine system 20 Correct Answer: releases hormones into the blood, targets specific regions, slow but long lasting, wide spread and sustained responses major endocrine glands Correct Answer: hypothalamus, pituitary, thyroid, adrenal, pancreas, pineal, parathyroid Paracrine intercellular communication Correct Answer: paracring - though ECF - paracrine chemical signals - primarily limited to local area where paracrine conc. high Autocrine intercellular communication Correct Answer: autocrine - through ECF - autocrine chemical signals - limited to cell that secretes chemical signals Endocrine intercellular communication Correct Answer: endocrine - through blood stream - hormonal chemical signals - targets distant tissues/ organs with correct receptors true hormone Correct Answer: made in one location, transported through blood stream to another location where they cause response (cells must have correct receptors) 21 water soluble Correct Answer: mostly peptides (75%), some catecholamines including adrenaline and noradrenaline, made and stroed until required, travels dissolved in blood, receptor in membrane as cant cross by itself, mechanism through 2nd messengers lipid soluble hormones Correct Answer: steriods, made from cholestrol as required, thyroid hormones are stored, travel in blood bound to carrier protein, receptor in cytoplasm/nucleus as can cross membrane, mechanism of altering gene transcription cellular response water soluble Correct Answer: ws hormone binds to cell surface receptor, hormone binding activates G protein, which activates/inhibits adenylyl cyclase/inc intercellular Ca2+, 2nd messenger production/recuction, downstream proteins/pathways activated/deactivated cellular response lipid soluble Correct Answer: ls hormone dissociates from carrier protein, diffuses across cell membrane, binds to intracellular receptor, hormone receptor complex acts as specific transcription facotr, target gene activated, mRNA generated, protein generated, mediates cell specific response negative feedback loop 22 Correct Answer: maintains constant level of hormones by stopping secretion when enough hormones present positive feedback loop Correct Answer: used to maintain homeostasis when extra of the hormone is being used, creates continuous stimulus for constant secretion pancreas Correct Answer: both endo and exocrine, exocrine gland as cells of pancreatic acini secrete digestive enzymes, endocrine as pancreatic islets, beta cells secrete insulin, alpha cells secrete glucagon blood glucose levels Correct Answer: too high = diabetes, too low = hypoglycemia, brain uses this throughout the day changing between fasting and fed state fasting state Correct Answer: mobilisation of nutrients and catabolic metabolism (breakdown of glycogen, protein and fat) fed state Correct Answer: cellular uptake of nutrients and anabolic metabolism (synthesis of glycogen, protein and fat) 23 Insulin Correct Answer: A peptide hormone produced and secreted by the Beta cells of the pancreas, targets liver and muscle, and allows them to take glucose out of the blood, only hormone to reduce BGC glucagon Correct Answer: A peptide hormone secreted by pancreatic islet alpha cells that raises blood glucose levels; an antagonistic hormone to insulin glycogen Correct Answer: stored form of glucose glycoenolysis Correct Answer: breakdown of glycogen gluconeogenesis Correct Answer: glucose synthesis hyposecretion Correct Answer: too little hormone hypersecretion 24 Correct Answer: too much hormone hyposensitive Correct Answer: too little or no response hypersensitive Correct Answer: too much response auto immunity Correct Answer: detruction of receptors/artificial stimulation of receptors genetic mutation Correct Answer: can cause loss or gain of function tumors Correct Answer: excess tissue leading to excess hormone release (sometimes can prevent release) hyperparathyroidism Correct Answer: excess PTH, bones become soft, deformed and fragile, varies blood levels of calcium and phosphate ions, promotes kidney stones composed of phosphate ions 25 type 1 diabetes Correct Answer: diabetes mellitus, hyposecretion, destruction of pancreatic beta cells, treatment by injection or infusions outcome of diabetes mellitus Correct Answer: heart problems and disrupted blood flow type 2 diabetes Correct Answer: diabetes mellitushyposensitive, desensitisation of insulin receptor, associated with obesity, treatment by change in diet and exercise, various medications growth hormone Correct Answer: hormone produced by hypothalamus and pituitary gland pituitary gland Correct Answer: located at base of brain, attached to hypothalamus pituitary hormone Correct Answer: connected to hypothalamus via neural tissue, controlled secretion by hypothalamus, some stimulate target cells, some stimulate secretion of hormones by other glands posterior pituitary gland 26 Correct Answer: secrete hormones directly into blood when stimulated by hypothalamus, hormones stored on axon terminals, releases antidiuretic hormone and ocytocin antidiuretic hormone Correct Answer: stimulates the kidney to reabsorb water (kidneys conserve water when body dehydrates oxytocin Correct Answer: Stimulates contraction of uterus (during childbirth, is +ve feedback) and mammary gland cells (milk release during breast feeding) anterior pituitary gland Correct Answer: connected to hypothalamus via blood vessels, hormone released from hypothalamus into blood stream is a releasing/inhibitory hormone to the anterior pituitary gland to release or not anterior pituitary hormones Correct Answer: growth hormone, thyroid stimulating, prolactin, FSH and LH, ACTH anterior pituitary target glands Correct Answer: liver, thyroid, mammary, gonads, adrenal cortex 27 direct effects muscle Correct Answer: growth hormone, stimulates protein synthesis and inhibits uptake of glucose direct effects liver Correct Answer: growth hormone, synthesis of glucose is stimulated direct effects fat Correct Answer: growth hormone, increase trigylceride breakdown in adipose tissue indirect effects Correct Answer: growth hormone, promotes growth of bones muscle and other tissues by causing release of cell division promoting somatomedin C night Correct Answer: peak of growth hormones levels throughout the day puberty Correct Answer: peak of growth hormone levels throughout lifetime adrenal glands Correct Answer: triangular and quite small, 2 types of tissue, sit above kidneys lateral to spinal cord, 2 glands - adrenal cortex and adrenal medulla 28 adrenal cortex Correct Answer: outer region of adrenal gland, 3 layers, secretes steroid hormones, outer layer secretes aldosterone, middle secretes cortisol, inner secretes androgens adrenal medulla Correct Answer: central region of adrenal glands, secretes mainly adrenaline cortisol Correct Answer: steroid produced by cholestrol when required in adrenal cortex, carried in blood by carrier protein, diffuses through lipid bilayers, increases production of mRNA for specific genes which is then transcribed and translated into protein which has effect within cell, slow waking up Correct Answer: peak for cortisol secretion uses of cortisol Correct Answer: inc. blood glucose conc, inc. fat, protein and carb metabolism to maintain BGC, upregulating immune responses, inc. blood pressure, inc. heart rate and blood vessel tone and contraction, activation of CNS addisons disease 29 Correct Answer: too little cortisol, leads to inc. ACTH secretion, excess ACTH stimulates melanin synthesis, blood blood pressure and weakness cushings disease Correct Answer: too much cortisol, high blood pressure, weakness / muscle wasting noradrenaline hormone Correct Answer: secreted as part of sympathetic nervous systems response to stress adrenaline hormone Correct Answer: stored, water soluble hormone, very fast, hormone - protein receptor - activated G protein - secondary messenger pathway - amplified cellular response stress response Correct Answer: stress stimulus activates hypothalamus which organises response and activates adrenal glands, SNS, posterior lobe of pituitary gland and then body responds appropriately thyroid gland Correct Answer: located below the larynx on anterior and lateral surfaces of trachea, secretes thyroid hormone and calcitonin 30 thyroid gland composition Correct Answer: gland made of small spherical sacs called follicles, each follicle surrounded by follicular cells and is site of thyroid hormone synthesis, clear cells / C cells lie in clusters between collicles and make hormone calcitonin thyroid hormone synthesis Correct Answer: iodine into follicle from blood and into follicle cavity - follicle cells release protein TGB into follicle, iodised TGB moved into follicular cells, thyroid hormones detach from TGB as needed (T3 & T4) bound to carrier protien move to target (45 mins to days) basal metabolic rate Correct Answer: bodys rate of energy expenditure under basal conditions (lying down, no muscle movement, awake, 12-18hrs fasted) uses of thyroid hormones Correct Answer: required for normal growth, alertness, metabolism effect of thyroid hormone Correct Answer: inc. body heat production, stimulates fatty acid oxidation, increases proteolysis, stimulates carbohydrate metabolism 31 infantile hypothyroidism Correct Answer: not enough thyroid hormone, low metabolic rate, cold intolerant, growth is retarded, brain development is inhibited, lack of iodine in mothers diet graves disease Correct Answer: too much thyroid hormone secretion, high metabolic rate, weight loss, inc. HR, nervousness, hair loss, exoptithalmos, thyroid swelling calcium Correct Answer: essential for many functions, i.e. contraction of muscles and release of neurotransmitters, bone is major store, rapid exchanges of calcium between bone and blood, 3 hormones involved, PTH, calcitriol and calcitonin parathyroid gland Correct Answer: located on posterior of lateral flaps of thyroid, secrete PTH which is essential for life hypoclycemia Correct Answer: blood calcium too low, inc. excitability of nervous system, leads to muscle tremors, spasms, or cramps, when very low can get paraesthesia in hands and face, muscle cramps, and in some cases the muscles of the larynx may contract slightly/shut off airflow 32 Hypoglycemia caused by Correct Answer: vitamin D deficiency, diarrhoea, thyroid tumors, underactive/removal of parathyroid glands, pregnancy and lactation hypergycemia Correct Answer: too much calcium in blood, nerve muscle cells less responsive and excitable, can lead to depression of nervous system, emotional disturbances, muscle weakness, potential cardiac arrest, need larger AP to overcome higher threshold set point Correct Answer: the point at which one's body tries maintain extra factors to stress response short term Correct Answer: inc. mental alertness, inc. energy use in all cells, changes in circulation, inc. HR and respiratory rate, change in blood vessel diameter, mobilization of glycogen and lipid, inc. sweat gland secretion, reduction in digestive activity extra factors to stress response short term nervous system Correct Answer: inc. reflex response rate, change in pupil diameter extra factors to stress response long term Correct Answer: increasing severity, hair loss, ulcers, tremors in muscles, heart attack, insomnia, personality changes etc 33 goitre Correct Answer: iodine deficiency, when stored TH is depleted TRH and TSH secretion increases, unable to do this with lack of iodine, therefore lose negative feedback, and over stimulation of thyroid gland, excess TSH stimulates growth of thyroid gland viruses Correct Answer: small, take over the cell and role of the cell, can kill it, cant self replicate bacteria Correct Answer: smallish, living and can replicate on own, use the bodies nutrient fungi Correct Answer: large ish, eukaryotic, breakdown tissues, common in weaker immune systems protzoa Correct Answer: larger (mm rather than nm), malaria etc. pathogens Correct Answer: Microbes that cause disease 34 lymphatic system Correct Answer: Composed of a network of vessels, ducts, nodes, and organs. Provides defense against infection, composed of primary and secondary organs primary lymphatic organs Correct Answer: production of white blood cells (lymphocytes), thymus and bone marrow thymus Correct Answer: school for white blood cells (T cells), learn how to react to self and pathogens, thymus gets smaller as you age, TCR gene rearrangement bone marrow Correct Answer: source of stem cells that develop into cells of the innate and adaptive immune system secondary lymphatic organs Correct Answer: sites where immune responses are initiated (swelling is the immune system dividing itself so more to fight disease), spleen and lymph nodes spleen 35 Correct Answer: site of initiation for immune responses against blood-borne pathogens lymph nodes Correct Answer: located along lymphatic vessels, lymph fluid from blood and tissue is filtered, site of initiation of immune responses (local) layers to the immune systems defence Correct Answer: chemical and physical barriers (skin, chemical defenses on skin), innate, adaptive chemical and physical barriers Correct Answer: skin (physical), and chemical (antimicrobial peptides, mucous membranes) skin (physical barrier) Correct Answer: made of the epidermis, dermis, has constant renewal of outer layer, dendritic cell at bottom of epidermis layer epidermis Correct Answer: dead cells on the outermost layer of skin, keratin, phagocytic immune cells 36 dermis Correct Answer: thick layer of connective tissue, collagen and blood vessels and phagocytic immune cells, alive layer of skin antimicrobial peptides Correct Answer: 'skin defensins', form pores in microbial cell membranes, composed of lysosome, sebum, and salt lysosome Correct Answer: breaks down bacterial cell walls sebum Correct Answer: low pH, prevents microbial growth salt Correct Answer: hypertonic, prevents microbial growth mucous membranes Correct Answer: 1-2 layers, in the ocular, respiritory, oral, urogenital (lines parts of body exposed to air), cillia keep mucus moving to pharynx, main parts are the epithelium, good example in stomach, gall bladder, intestines, mucus, defensins, lysosomes 37 epitelium Correct Answer: tightly packed live cells, constantly renewed, mucus-producing goblet cells innate immune system Correct Answer: already in place, rapid, fixed, limited specificities (recognises pathogens in general), has no memory adaptive immune system Correct Answer: improves during the response, slow, variable, highly specific (recognise specific pathogens), has long term memory composition of blood Correct Answer: 55% plasma (proteins i.e. antibodies, other solutes i.e enzymes, water i.e. immunity chemical messengers), 45% formed elements (platelets i.e clotting factors, white blood cells i.e. leukocytes, red blood cells) bone marrow stem cells Correct Answer: pluripotent and can become almost anything blood cell lineages Correct Answer: erythroid, myeloid, lymphoid 38 erythroid Correct Answer: red blood cells, derived from hematopoietic stem cells in bone marrow myeloid Correct Answer: Granulocytes, monocytes, dendritic cells, platelets (innate immune cells), derived from hematopoietic stem cells in bone marrow, white blood cells lymphoid Correct Answer: B and T lymphocytes (adaptive immune cells), derived from hematopoietc stem cells, white blood cells neutrophils Correct Answer: A type of white blood cell (granulocyte) that engulfs invading microbes and contributes to the nonspecific defenses of the body against disease, numbers increase during infection, move into tissues during inflammation mast cells Correct Answer: line mucosal surfaces, are in tissues, release granulocytes that attract white blood cells to area of damage monocyte 39 Correct Answer: present in blood, low phagocytosis, leave blood and develop into macrophages macrophages Correct Answer: spleen and liver, high phagocytosis, become resident (sterile) or migratory, important functions of phagocytosis, release of chemical messengers, show information about pathogenic microbes to T cells (linking innate and adaptive) dendritic cells Correct Answer: link innate and immune systems, found in low numbers in blood and all tissues in contact with environment (large SA), most important cells to help trigger adaptive immune response, phagocytic, most potent antigen presenting cell movement of immune system cells Correct Answer: cells move around the body, carried in blood or lymph, cells can leave the blood to enter the tissues, lymph in tissues collects into lymphatic vessels and drain into lymph nodes phagocytic cells Correct Answer: have recognition receptors which recognise common building blocks of bacteria and yeast, signalling end inside the cytoplasm, sometimes gets taken in by the phagolytic cells, signalling end sends upregulating signals to nucleus 40 common building blocks of bacteria Correct Answer: cell wall: lipopolysaccharid/entotoxins, lipoteichoic acid, flagellin, and nucleic acid: unmethylated CpG DNA common building blocks of viruses Correct Answer: nucleic acid: ssRNA, dsRNA, has envelope and nucleocapsid, nucleic acid fever/pyrexia Correct Answer: abronally high temp causing resetting of thermostat in hypothalamus, pyrogens released by immune system cells, phagocytes produce chemical messenger phagocytic produced chemical messenger Correct Answer: pyrogen interleukin (IL-1) after intergrating bacteria (what tells the hypothalamus to reset temp and become hotter ) dec. phagocytosis = dec. IL-1 = dec. temp Diabetes mellitus Correct Answer: Too little/poor insulin receptors Addisons disease 41 Correct Answer: Too little cortisol, inc. ACTH secretion, stimulates melanin synthesis, low BP and weakness Cushings disease Correct Answer: Too much cortisol, high BP, weakness Infantile hypothyroidism Correct Answer: Hyposecretion (too little thyroid hormone), low metabolic rate, cold intolerant, growth is retarded, brain development inhibited (lack of iodine) Graves disease Correct Answer: Hyperthyroidism (too much thyroid hormone), high metabolic rate, weight loss, increased heart rate, nervousness. Hair loss, exoptithalmos, Thyroid swelling Hypocalcemia Correct Answer: deficient calcium in the blood, inc. excitability or nervous system, muscle tremors spasms or cramps, paraesthesia, muscle cramps, vitamin D deficiency, thyroid tumors, removal/under active parathyroid glands Hypercalcemia 42 Correct Answer: excessive calcium in the blood, nerve muscles less responsive, depression of nervous system, emotional disturbances, muscle weaknesses, sluggish reflexes, cardiac arrest, need larger AP to overcome threshold Goitre Correct Answer: Iodine deficiency disorder, thyroid gland unable to make enough TH, when depleted TRH and TSH secretion increase, without iodine TH can't be made, loss of -ve feedback loop, over stimulation and growth of thyroid gland inflammatory response Correct Answer: chemical signals from mast cells attract more cells to injury/infection, neutrophils enter blood from bone marrow and cling to capillary walls, flattened out and can squeeze through capilary vessel walls, as chem signals have made capillaries leakier hence blood leakage stages to phagocytosis Correct Answer: 1. phagocyte adheres to pathogen or debris, 2. phagocyte forms pseudopods that engulf particles, 3. lysosome fuses with phagocytic vessicle forming phagolysosome, 4. toxic compounds and lysosomal enzymes destroy pathogens, 5. sometimes exocytosis of vesicle removes indigestivle and residual material key to phagocytosis 43 Correct Answer: low pH (acidic environment), reactive ocyden and reactive nitrogen intermediates, enzymes (proteases, lipases, nucleases) complement cascade Correct Answer: complement - 9 major proteins/protein complexes act in sequence to clear pathofens from blood and tissues, 1. label pathogens (opsonisation), 2. recruit phagocytes (chemotaxis), 3. destroy pathogens (lysis) Classic complement pathway Correct Answer: antibody bound to pathogen binds complement (adaptive immune response) Alternative complement pathway Correct Answer: pathogen binds complement to surface/pathogen component Lectin complement pathway Correct Answer: carbohydrate components of microbes bind complelemt complement pathway converge Correct Answer: classical, alternative and lectin pathways converge to amplify with C3 convertase, resulting in labeling, destruction and recruitment labelling complement cascade 44 Correct Answer: oponisation (labels pathofens which bind to complement receptors on phagocytes) C3b, coating microbe with antibody or C3b innate immunity destruction complement cascade Correct Answer: membrane attack complex formation: pores in bacterial cells -> death C9, microbes coated in C3b and phagocytosed, assembly of MAC complex causes lysis recruitment complement cascade Correct Answer: complement proteins act as peptide mediators of inflammation and recruit phagocytes into site (mast cells degranulated byC3a and C5a), inflammatory mediators released including proteins that attract phagocytes leukocytes Correct Answer: minor component of blood but most important cells in immunity dendritic cell migration Correct Answer: move from skin to draining lymph node where they present peptides on MHC to other which blood cells (T cells), CD4 help B cells make antibody (L35), CD8 become cytotoxic and kill virus infected cells and cancer cells (L34) antigen 45 Correct Answer: anything that has the potential to be recognised by immune system, foreign antigen from 'outside' i.e. transplants, pathogens etc. , auto (self)-antigen, immune system normally tolerant of self-antifen, can be recognised in auto immune disorders antigen uptake Correct Answer: in the innate response, for clearance of pathogens, in adaptive response L34, for presentation to T cells evolution of immunity Correct Answer: invertebreats have innate immunity only, vertebrates have innate and adaptive systems MHC expression Correct Answer: MHC-I presents endogenous (intracellular) antigen, expressed on all nucleated cells, MHC-II presents on exogenous (extracellular) antigen, expressed only on antigen presenting cells endogenous antigens Correct Answer: peptides loaded onto MHC class 1 molecules for immune surveillance MHC-I antigen processing 46 Correct Answer: antigenic proteins are degraded to peptides in cytoplasm, peptides are imported into endoplasmic reticulum, peptide loading of MHC-I takes place in ER exogenous antigens Correct Answer: peptides loaded onto MHC class II molecules for immune surveillance (phagocytosis of exogenous antigen) MHC-II antigen processing Correct Answer: Antigenic proteins are degraded in acidic phagolysosome, peptide loading of MHC-II takes place in phagolysosome T cells Correct Answer: lymphocytes that arise in the bone marrow and fully develop in thymus, T cells express T cell receptor (TCR) with co-receptors (either CD4 or CD8), recognise MHC / peptide complexes Bone marrow Correct Answer: production of T cells precursors T cell receptors Correct Answer: immature T cells (TCR genes in germline state) in bone marrow, TCR gene rearrangement in thymus, mature (naive) T cells expressing unique antigen receptors 47 Thymic gene rearrangement Correct Answer: immature T cells (thymocytes) rearrange the 'variable' parts of their TCR genes in thymus, process is essentially random, ensures individual T cells are unique in terms of TCR, creates diversity in T cell repertoire TCR and MHC Correct Answer: T cells express T cell receptors which recognise peptides and MHC, the variable TCR allows for recognition of different peptides and MHC MHC Correct Answer: Major Histocompatability Complex proteins -- surface of tissues and blood cells for recognition of Self vs Non-self (MHC I) CD4 and CD8 Correct Answer: the 'co receptors' on T cells, help with recognition and binding of MHC-II and MHC-I /peptides T cell differentiation Correct Answer: T cells that have not been activated by MHC/peptide are 'naive', activated T cells are also known as 'effector cells' CD4 T helper cells 48 Correct Answer: Recognises MHC-II/peptide, releases cytokines which helps activate CD8 T cells become cytotoxic, helps B cell make antibody CD8 T cell Correct Answer: recognises MHC-I/peptide, develops into 'cytotoxic T lymphocyte' (CTL) aka 'cytotoxic T cell' Cytotoxic T lymphocytes Correct Answer: granules full of cell killing proteins stimulates cells to use own energy to kill itself when granules released into cell, released into virally-infected cell which kills the cell (apoptosis) adaptive defenses Correct Answer: humoral immunity, cellular immunity, origin in B and T lymphocyte precurors originate in red bone marrow, lymphocyte precursors destined to become T cells migrate in blood to thymus and mature there, B cells mature in bone marrow, during maturation lymphocytes develop immunocompetence and self tolerance Helper T cells in humoral immunity Correct Answer: T cell binds with the self-nonself complexes of a B cell that has encoutered its antigen and is displaying it on MHC II on its surface, TH cell releases interleukins as co-stimulatory signals to complete B cell activation 49 helper T cells in cellular immunity Correct Answer: TH cell binds dendritic cell, stimulates dendritic cell to express costimulatory molecules, dendritic cell can not activate CD8 cell with help of interleukin 2 secreted by TH cell Memory T cells Correct Answer: in addition to the formation of 'effector' cells, T cell activation results in the formation of memory T cells, memory CD4 or CD8 T cells reside in the body for long periods of time, memory T cells become effector cells much quicker than naive T cells Human immunideficiency virus (HIV) Correct Answer: HIV-receptor is CD4 molecule on CD4 T cells, infection leads to loss of CD4 T cells, help both humoral (B cell/antibody) and cytotoxic responses, HIV infection impacts on immunity to microbes (fungi, bacterial and virus) and to cancer B cells Correct Answer: are lymphocytes that develop in the bone marrow, express unique antigen receptors (BCR or secreted antibody) plasma cells are activated B cells that secrete antibody, memory B cells provide memory B cell receptor 50 Correct Answer: the surface of each B cell is covered with roughly 100,000 BCR (mainly IgM/IgD antibodies), the BCR binds antigen and activates B cell functions of antibody Correct Answer: neutralisation, opsonisation, complement activation viral neutralisation Correct Answer: virus attach to cell receptors to infect, antibodies stop ability to attach to cell receptor, "blocking the pathogen or toxigenic products from affecting host cells" opsonisation Correct Answer: bacterium blasted with antibody makes it "tastier" antibody facilitates destruction (easier to be eaten by macrophage) activation of complement system Correct Answer: complement proteins bind to receptors of foreign cell, releases the protein and forms membrane attack complex, flow of ions through the pore, this is the innate system meshed with the adaptive system IgG Correct Answer: class of i