Physiology Zool 2420 Exam 2 review PDF

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This was an exam review professor Taylor had given out and I have filled out all topics with the information that was on the exam ...

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Physiology- (ZOOL 2420) -- Study Guide- Exam #2 (Chapters 7-11) Disclaimer: This document is intended as an aide in studying for the exam. Not everything on this sheet will be on the exam, and conversely there may be questions on the exam not covered on the study guide. Concepts central nervous system Brain and spinal cord Integration and control center peripheral nervous system Everything else (Nerves, vision, Senses.) Afferent and Efferent information neuron nerve cells, generate and conduct nerve impulses anterograde transport Away from the cell body Soma → axon terminals (Kinesin is the protein that moves that direction) retrograde transport Moves towards cell body (Dynein is the protein that moves that direction) synapse Space between the end of axon terminal to a dendrite or soma and transfers the signal from electrical to chemical all or none principle AN action potential can or CANNOT happen. Because it has to reach threshold IPSP Inhibitory Postsynaptic potential - Hyperpolarization EPSP Excitatory Postsynaptic potential - Depolarization frequency coding - Recording the frequency of an action potential presynaptic modulation - Facilitation=release MORE neurotransmitters Inhibition + releases LESS neurotransmitters (not to fire as much) acetylcholine (ACh) Most abundant N.T. in the CNS and PNS. Binds to the nicotinic receptors and muscarinic. Glial cells 90% of all cells in the nervous system; “glue”; Support, insulate and protect 1. Astrocytes -CNS; Support, guides migration, controls environment. Provide blood to neurons; Control chemical environment 2. Microglial cells - CNS; touch and monitor neuros, Migrate towards injured neurons. (clean up crew) Phagocytize microorganisms and neuronal derby. 3. Ependymal cell - CNS; makes cerebrospinal fluid (CSF) ; Makes it from blood ; Alligin cavities of the central nervous system ; ciliated 4. Oligodendrocytes - CNS; Myelinate several sections of axons 5. Satellite cells - PNS ; Maintain synapses of target cells. 6. Schwann cell - One schwann cell myelinates ONE sections of ONE axon. Insulation of axons Blood-brain barrier - Astrocytes use their feet to bind to molecules to tell them to get closer forming the Blood Brain Barrier. White matter* Myelinated fibers and fiber tracts Grey matter* Mainly somas Cerebrospinal fluid - CSF - epidermal cells (glial cell) filters the plasma out of the blood to make CSF

Stroke Decrease blood supply to the brain. Vein breaks or gets blocked. Corpus callosum - Connects the two hemispheres of the brain Spinal cord - Part of the CNS (white matter on outside, gray matter on the inside.) CSF Spinal nerve- 31 pairs in the spinal cord all traveling to the periphery Gyrus - Peak/mountain part of the brains Sulcus - Sunken grooves of the brain Lobe- Different parts of brain. Frontal lobe - Personality and higher order of thinking. (develops last) Temporal lobe - Hearing and other auditory processes. Parietal Lobes - Sensations (touch) Occipital lobe - Vision (eyes) Longitudinal fissure - Separates the 2 hemispheres of the brain Reflex Muscle spindle stretch reflex- Monosynaptic reflex Crossed-extensor reflexes- Multiple synapses are used to get signal where it needs to go. **Upper motor neuron- Basal nuclei to the spine **Lower motor neuron-Spine- to effector organ Afferent neuron - Signal moving towards the CNS (brain) Efferent neuron - SIgnal moving FROM/away from brain Electroencephalography (EEG) Measures the brain activite waves in brain without being invasive. Can measure when awake or asleep Plasticity Brain's ability to change whien learning. Consolidation of Short-term memory to Long-term memory- Short term is stored in Hippocampus. Brain gets bigger(surface area) creates more receptors. Yet if you don’t repeat the information to keep it firing you will down regulate. Sensory systems - Special senses; and Somatosensory system(somatic; proprioception; mechanoreceptors; thermoreceptors; nociceptors-’pain’) Special senses- 1. taste 2. vision 3. Sound 4. Equilibrium 5. Smell (olfactory) Sensory transduction - How a stimulus is changed into a electrical signal by opening or closing ion channels. Receptor adaptation - A decrease in receptor potential because of a the presents of constant stimulus. Sensory unit - signal AFFERENT(AT the CNS) neuron; and all others associated with it. Sensory coding - Frequency, # of receptors activated, and stronger stimulus. Stimulus location - Receptive fields of the somatic senses. (size of the receptive field, overlap of receptive field) Lateral inhibition ***Sensation - Parietal lobes ***Perception Retina - two layers 1. Pigmented layer: outer, single cell layer, absorb light to prevent scattering, stores vitamin A 2. Neural layer: Photoreceptors, bipolar cells, ganglion cells **Photoreceptors Fovea - only has CONES; tiny pit within the macula (macula - region lateral to the blind spot of each eye) Optic disk - made of gangelia cells; optic nerve exits the eye “blind spot”

Emmetropia - ‘Normal vision’ a person can see close up and far away object clearly. Myopia- “MY CAVE IS NEAR” Nearsighted, Concave glasses will correct it. (The lens is Convex) Hyperopia- Farsighted vision, Convex glasses will correct it. (The lens is concave.) Cochlea - receptor organ for hearing Vestibular apparatus - equilibrium receptors in the semicircular canals and vestibule Cristae Cupula - very center of the snail like structure; Low pitch it heard at the end high pitch is heard at the beginning Kinocillium v- hair cells; Semicircular canal - Involved with equilibrium; 3 planes of space Taste buds - Receptors on the tongue 1. Sweet - Sugar 2. Sour - Acids 3. Salty - Metalloids, Metal ions 4. Bitter - Alkaloids (Caffeine) 5. Umami - MSG Olfactory binding proteins - Chemical must dissolve in the mucus, then the binding proteins deliver olfactives to receptors Effectors Preganglionic neuron - Always release Acetylcholine to nicotinic receptors on the Postganglionic neuron Postganglionic neuron - Have Nicotinic receptors; and releases Norepinephrine in the sympathetic to effector organs with adrenergic receptors; IN the Parasympathetic it releases Acetylcholine to effector organs with muscarinic cholinergic receptors Dual innervation of the ANS - 1. All visceral organs served by BOTH 2. Divisions cause OPPOSITE EFFECTS 3. Counterbalance: maintains homeostasis Spinal nerves - Connect to the grey matter lateral horns of the brain stem. Spinal Roots Varicosities

Guided Questions:

What are the components of a neuron and their corresponding functions? Dentraites, Soma, Axon Hillock, axon, axon terminals. Dendrites - receive information signals Soma- Receive signals Axon Hillock - Starts signal; TONS of Voltage gated channels(Na+ channel) Axon- Na+ and K+ voltage gated channels Axon terminals- Ca+ gated channels to signal exocytosis

Describe the types of glial cells and their functions. Where is each located (CNS vs. PNS)? CNS: 1. Oligodendrocytes - Myelinate (several axons) 2. Astrocytes - Blood brain barrier (everything else) 3. Microglial cells - fights diseases; goes to injured cells; touch and monitor cells 4. ependymal cells - Makes cerebrospinal fluid (CSF) by filtering blood and taking the plasma PNS: 1. Schwann cells - Myelinate (only ONE section of ONE axon/wrap) 2. Satellite cells - maintain synapses (everything else; astrocytes of the PNS) Compare graded potentials to action potentials. What are temporal and spatial summations? Graded potentials = signal received in the soma and can be bigger than others and goes towards axon hillock, Causes small change in membrane potential, Decay rapidly, travel SMALL distance Action potentials = Same neuron as the SAME magnitude for action potential, Does not decay as much, Allows long distance communication, ONLY muscle cells and axons. Can only happen when reaches threshold(all or nothing) Describe the phases of an action potential. What happens with voltage-gated sodium and potassium channels during each phase? Phase 1: when it reaches threshold and reaches the action potential; Rapid opening of VGNa+C’s ; Slow closing VGNa+C’s (Depolarization) Phase 2: Opening VGK+C’s ; (Repolarization) Phase 3: Slow closing VGK+C’s ; (hyperpolarization) Because potassium is leaving the cell making it more negative. ; Na/K--ATPase What are the types of refractory periods? What is the consequence of each? Absolute refractory - you CANNOT have another action potential because of the inactivation gates. Relative refractory - you CAN have another action potential, though it is difficult. You have to make up for the K+ leaving the cell. (hyperpolarization) Describe the factors influencing conduction velocity of an action potential? Compare fast and slow pain. The size and myelination of the nociceptors will determine how fast or slow the signal travels. Fast: big and myelinated (1st pain) A-delta fibers, shard and easy to locate Slow: small and unmyelinated.(2nd pain) C- fibers, dull ache, Poorly localized. Compare ionotropic and metabotropic receptors. Ionotropic - Ion channel- Nicotine and acetylcholine receptor. ALWAYS excitatory. Na+ and/or Ca2+ permeable Metabotropic receptor -Changes the shape of the receptors to unbind the g-protein to send a signal. Muscarinic; contains G-protein coupled receptor. (second messenger system, amplifies

signal, can affect ion channels.)

**Describe the types of neurotransmitters. What is the function of each type? 1. Acetylcholine : PNS&CNS; Synthesized in axon terminal; choline acetyltransferase(ChAT) = enzyme that synthesizes to acetylcholine ; Acetylcholinesterase Breaks down to Acetate & choline 2. Biogenic amines- Derived from amino acids; Catecholamines are Dopamine, epinephrine and norepinephrine, those are broken down by Monoamine oxidase(MOA). Then there is Serotonin(reuptaken)SSRI, histamine. 3. Amino acida. Excitatory synapses - Glutamate, Aspartate b. Inhibitory - GABA, Glycine 4. Purines - ATP(enteric nervous system, and GI Tract), GTP, ADP, AMP; CNS & PNS 5. Neuropeptides- Short chains of amino acids, put with other transmitters, Modulates responses from other neurotransmitters. (EX: endorphins, vasopressin, oxytocin, TRH) 6. Gasses & Lipids- Nitric oxide (NO) excitatory and inhibitory ; fat soluble; retrograde(because they have the ability to go backwards) and kinesin carries anterograde (away from soma) 7. Endocannabinoids - CB1 7 CB2 which are most common receptors in body; THC binds to CB1 & CB2. synthesized by membrane phospholipids. a. EX: anadamines which is an endogenous endocannabinoids

Compare the ventral horn to the dorsal horn in terms of information received/sent and if there are cell bodies or tracts within those regions. Goes into the dorsal horn(afferent) has a sensory signal and is converted at the dorsal ganglia and goes out the ventral horn(efferent) as a motor/voluntary movement. What are the lobes of the brain? What is/are the function(s) of each? 1. Frontal lobe - Last to develop; higher order of thinking 2. Temporal lobe -auditory (hearing), Ventral stream information a. medial temporal lobe - memory, emotion 3. Parietal lobe - Sensation, spatial reasoning 4. Occipital lobe - Visual cortex

What is brain lateralization? Right brain controls left side Left brain controls right side What are the basal nuclei (ganglia)? What are their functions? Repetitive movement. Parkinson's disease - Midbrain cells are dying that cannot communicate to stop unwanted movement, hard to start wanted movement. Huntington's disease- Actually ganglia cells are dying in the brain, can’t control unwanted movement

What are the areas of the diencephalon? What are their functions? 1. Thalamus - relay station for sensory to the cortex 2. Hypothalamus - Important ANS center a. Body temp b. BP c. food intake d. pupil size e. water balance 3. Epithalamus - Houses pineal body(sleep; secrets or stops melatonin) What is the function of the limbic system and what structures allow for emotional memory to be stored? 1. Hippocampus - Learning memory 2. Amygdala - emotion 3. Rhinencephalon (Olfactory) - Smell brings memories 4. Parts of the thalamus and hypothalamus - Emotional memories *** What are the differences and similarities between the muscle spindle stretch and the withdrawal and crossed-extensor reflexes? Stretch of the spindle is used to send signal, only 1 synapse is used. Crossed extensor reflexes multiple synapses are used Describe the functions of the cerebellum. Coordination and voluntary motor movements, balance, equilibrium. Compare and contrast Wernicke’s and Broca’s aphasia. Wernicke’s area- Cannot comprehend but talk fine but doesn’t make sense Broca’s - Can comprehend but cannot speak complete sentences. Describe the two types of sleep. How do REM sleep waves compare to brain waves during the awake state? REM sleep - most like the waves when awake(beta and Alpha waves) Non REM sleep - delta & K complex waves Describe the divisions of the PNS. Autonomic nervous system: Functions of the body you don’t voluntary control(digestion, heart beat) Somatic: Proproceptions, & Senses(Nocioreceptors, chemoreceptors, thermoreceptors, mechanoreceptors, Proprioceptors) What is lateral inhibition? How is it involved in coding of a stimulus? Lateral inhibition is the inhibition of N.T. in the lateral receptive fields. What are the types of somatosensory receptors? How does each function? 1. Somatic- sensations of the skin(outside of body) 2. Proprioception- Perception of limb and body positions(Aware of where your body is positioned in space)

What is the body’s response to pain? How is it perceived? How is it modulated? Nociceptors are pain receptors, they are Delta-A or C fibers. Response because of tissue damage, or potential damage. Elicits Autonomic responses(B.P. ; H.R. ; Sweating ; swelling). Also elicits emotional responses(fear, anxiety; Depends on past experiences) What are the layers of the retina? What types of cells are in each? How are they connected? Two layers: 1. Pigmented layer: outer single-cell layer, Absorbs light to prevent scattering, stores Vitamin A. 2. Neural layer (3 types of neurons) -Photoreceptors (rods & cons; only graded potentials) -Bipolar cells (only graded potentials) -Ganglion cells (only place for and action potential) Compare and contrast rods and cones. Cons process color. RODS are for lighting What structures allow for sound amplification in the ear? Bones in the inner ear amplify sound: Malleus(hammer), Incus(anvil), Stapes(stirrup) **Explain signal transduction for sound in the cochlea (include the structure and function of the organ of corti, and the cation that is responsible for the depolarization of the hair cells). Signal is amlified by the bones in the ear; the corti is then the receptor organ for hearing(hair cells). **What do the semicircular canals measure? How is this process accomplished? They measure your up and down motions(where you are in space) Measure your equilibrium and balance. What does each of the otolith organs measure? How does it do so? What are the primary tastes? 1. Sweet - sugar 2. sour - acids 3. bitter - alkaloids 4. salty - metal ions 5. Umami - MSG **Describe olfactory signal transduction. The smell dissolves in the mucus and the olfactory binding proteins transport them the the olfactory receptors. Compare and contrast the somatic and autonomic nervous systems. Somatic: proproceptions and somatosensory Autonomic: Functions you don’t voluntary make (BP, HR, Digestion) Compare and contrast the sympathetic and parasympathetic divisions of the ANS. Parasympathetic: Rest and digest Sympathtic: fight and flight

Compare and contrast nicotinic and muscarinic acetylcholine receptors (include locations in the nervous system). Muscarinic receptors are going to be at all effector organs BUT only used by the Parasympathetic Nervous System; can be excitatory or inhibitory. Nicotinic receptors are on all postsynaptic ganglion; always excitatory. What are the roles of each of the types of adrenergic receptors in the ANS. Adrenergic receptors are only found in effector organs of the sympathetic nervous system. Norepinephrine and epinephrine; NOREPINEPHRINE is used MOST. Depends on the organ of how it is affected. Describe the structure and function of autonomic neuroeffector junctions. Refer to picture slide in CH. 11. What are the neurotransmitters and receptors of the ANS? Be sure to describe the neurotransmitters released from pre-and post-ganglionic neurons for both parasympathetic and sympathetic divisions. Also include the receptors located on pre-and post-ganglionic neurons and effector organs for both parasympathetic and sympathetic divisions. Refer to picture/slide in CH. 11.

** electro probe into neuron what will signal do/HOw will it travel?...