Details Title: Biology 175 Chap 1 - Midterm Description: Human Physiology Total Flash Cards: 321 Created: 09/26/2008 08:45:10		New Users: To study from this flashcard set, or to create your own your own study flash cards, REGISTER HERE. Existing Users: CLICK HERE. Additional Physiology Flashcards
Cards in this set: Term Homeostasis Definition Dynamic Constancy Term Intrinsic Homeostatis Definition control built into organ Term Extrinsic Homeostasis Definition control from outside of organ as in Nervous and Endocrine System Term Negative Feedback Definition Response opposes stimuli Term Positive Feedback Definition response enhances stimuli Term Negative Feedback Loop Definition Receptor (Sensor): detects deviation in set point Control Center: determines response Effector: Produces Response Term Types of Tissues Definition Epithelial Connective Muscular Nervous Term Epithelial Definition Protection Covers body surfaces and lines body cavities; has basement membrane; forms membranes and glands (Secretions); regularly replace; tightly joined cells with small matrix; nonvascular Term Classification of Epithelial Tissues by Layers Definition Simple: One Layer Stratified: Multilayer Term Simple Epithelia Definition Covers visceral organs; lining lumina and body cavities Term Stratified Epithelia Definition Two or more layers of cells; protection, strengthening or distention. Found in Epidermal layer of skin; lining of body openings, ducts and urinary bladder Term Classification of Epithelial Tissue by Shape Definition Squamous: flat Cuboidal: cube shaped Columnar: column-like Term Simple Squamous Definition Single layer of flat cells Diffusion and Filtration; covering visceral organs, lining of lumina and body cavities Term Simple Cuboidal Definition Single layer of cube-shaped cells; excretion, secretion or absorbtion. Located in capillary walls, alveoli of lungs, covering of visceral organs, lining of body cavities Term Simple Columnar Definition Single layer of nonciliated, tall, column shaped cells; protection, secretion and absorbtion. Found in lining of GI tract Term Simple Ciliated Columnar Definition Single layer of ciliated column shaped cells; transportation through ciliary motion, Found in lining of lumen of uterine tubes Term Pseudostratified ciliated columnar Definition Single layer of ciliated irregulary shaped cells with many goblet cells; protection, secretion and ciliary movement. Found in lining of respiratory passageways Term Stratified Squamous Definition Multilayered flat cells. Protection and pliability. Found in lining of oral and nasal cavities, vagina, anal canal and epidermis of skin Term Stratified Cuboidal Definition Usually two layers of cubes-shaped cells. Strengthens luminal walls. Located in larger ducts of sweat glands, salivary glands, thyroid and pancreas Term Transitional Epithelial Definition Numerous layers of round nonkeratinized cells. Relaxed and flexible; large and round; permits expansion and recoil. Located in Luminal walls and urinary bladder Term Connective Tissue Definition Loose and Dense Fluid: Blood and Lymph Support: Cartilage and Bone Term Loose Connective Tissue Definition Adipose Areola Reticular Term Adipose Tissue (Loose) Definition Padding and cusions; insolates; energy reserves. Located in deep skin, buttocks, breasts, padding around eyes and kidneys Term Areola (Loose Connective) Definition Packaging and holding organ together and in place. Attaches epithelia to underlying tissues. Found in skin, digestive, respiratory, reproductive, urinary, blood vessels and nerves. Term Reticular (Loose Connective Tissue) Definition Supportive Framework Located in liver, kidneys, spleen, lymph nodes, bone marrow. Found most everywhere in body but mostly in those places. Term Dense Connective Tissue Definition Regular and Irregular Packed with collagen fibers; dense, fibrous; fibers arranged next to each other Term Dense Regular (Connective Tissue) Definition Provides firm attachement; conducts pull of muscles; reduces friction between muscles; stabilizes relative position of bones. Located in tendons and ligaments. Term Dense Irregular (Connective Tissue) Definition Fibers arranged in an irregular way. Located in Capsules and Dermis Term Supportive Connective Tissue Definition Cartilage and Bone Term Cartilage Definition Flexible support and protection Three types: Hyaline Elastic Fibrocartilage Term Hyaline Cartilage (Supportive Connective Tissue) Definition Provides stiff but somewhat flexible support; reduces friction between boney surfaces. Located between tips of ribs and bones of the sternum; covering bone surfaces at synovial larynx, trachea, bronchi, and part of nasal septum. Term Elastic Cartilage (Supportive Connective Tissue) Definition Provides support but tolerates distortion without damage and returns to original shape Term Bone (Supportive Connective Tissue) Definition Formed of concentric layers of calcified material Three types of cells: osteoblasts osteocytes osteoclasps Term Muscle Connective Tissues Definition Skeletal Cardiac Smooth Term Skeletal Muscle (Connective Tissue) Definition Elongated, large, striated, multinucleated, voluntary, individually controlled. Lined up parallel to form bundles Term Smooth Muscle (Connective Tissue) Definition Not striated, involuntary. Found in walls of all hollow organs. Controlled by ANS. Long, spindle-shaped cells with one nucleus. Term Cardiac Muscle (Connective Tissue) Definition Striated, involuntary; found only in heart. Branched; intercalated discs between cells. Circulates and maintains blood through autonomic contraction. Term Blood (Loose of Fluid Connective Tissue) Definition Red Blood Cells-millions White Blood Cells-thousands Platlets-hundred thousands Term Lymph (Loose or Fluid Connective Tissue) Definition No cells Term Nervous Connective Tissue Definition consists of Neurons and Neuroglia (supporting glia cells) Term Neurons (Connective Tissue) Definition specialized for conducting electrical signals. Three basic components: Cell Body Dendrites Axon Term Neuron Cell Body (Connective Tissue) Definition Nucleus; metabolic center Term Dendrites (Connective Tissue) Definition highly branched extensions off cell body; receives input from other neurons and conducts to cell body Term Axon (Connective Tissue) Definition single,long extension off cell body; conducts nerve impulses to other cells or effector organs. Term Neuroglia (Connective Tissue) Definition Supporting/Glial cells-provide physical and functional support for neurons Term Atoms Definition Smallest unit of chemical elements. Composed of Nucleus (protons and neutrons) and Electron Shells Term Atomic Mass Definition Sum of protons and neutrons in an atom Term Atomic Number Definition number of protons in an atom Term Electron Shells Definition # of electrons = # of protons 1st shell has 2 electrons 2nd shell can have upto 8 electrons Term Valence Electrons Definition Only in the outer Electron Shell Can participate in chemical reactions and form bonds Term Isotopes Definition Different forms of the same atom Different # of neutrons Atomic # is the same; Atomic mass if different Term Inert Atoms Definition Outermost electron shell is completely saturated (full) Term Reactive Atoms Definition Outermost electron shell only paritally full Term Chemical Bonds Definition Molecules form by chemical bonding between Valence electrons Term Convalent Bonds Definition Atoms sharing Valence bonds Term Convalent Nonpolar Bonds Definition Electrons are shared equally between two atoms; Hydrophobic O2 and H2 Term Convalent Polar Bonds Definition Electrons are shared unequally in atoms; Hydrophilic Term Ions Definition charged atoms Term Ionic Bonds Definition Valence electrons are transferred from one atom to another (losing or gaining) Cation: + charged Anion: - charged Weaker than Polar Convalent Bonds Term Hydrogen Bonds Definition Form between molecules with polar convalent bonds; Hydrophilic Ex: in H2O negative oxygen atom attracts positive Hydrogen atom of adjacent molecules. Weaker than Ionic and Convalent Bonds Term pH Scale Definition H+ concentration of solution. 0-14 Scale H2O is 7 (neutral) Acids: 0-7 Bases: 7-14 Blood: 7.35-7.45 Acidosis < 7.35 Alkalosis > 7.45 Term Organic Molecules Definition Carbon, Hydrogen, Oxygen Carbon: 4 electrons in outer shell; bonds convalently to fill 8 electrons. Backbone to which all reactive functional groups are added Term Carbohydrates Definition Organic Molecule Carbon Hydrogen and Oxygen Monosaccharides Disaccharides Polysaccharides Term Monosaccharides Definition Simple Sugar (one sugar molecule) Glucose Fructose Galatose Term Disaccharides Definition Two monosaccharides joing convalently. Sucrose (glucose and fructose) Lactose (glucose and galatose) Maltose (malt sugar) Term Polysaccharides Definition Complex Carbohydrates Chains of Monosaccharides joined convalently: Starch in plants Glycogen in animals Stored in Liver and Skeletal Muscles Term Lipids Definition Insoluble in polar solvants. Hydrocarbon chains and rings Term Triglycerides Definition Made of one alcohol molecule (glycerol) and three fatty acids. Saturated - single convalent bonds Unsaturated- double bonds with hydrocarbon chains Term Ketone Bodies Definition Hydrolysis of triglycerides for energy.....excess is made into Ketone Bodies in the liver. Term Phosolipids Definition Lipids that contain a Phosophate group. Plasma Membrane is made up of a bilayer of Phosolipids. Phosphate portion is polar and hydrophilic. Lipid portion is nonpolar and hydrophobic. Term Steroids Definition Nonpolar and Hydrophobic. Three 6-carbon rings joined to a 5-carbon ring. Term Cholesterol Definition Percursor to steroid hormones. Component of cell membrane. LDL and HDL Term Proteins-Amino Acids Definition Long chain of amino acids. 20 different amino acids. Two types: Essential-not produced in the body Nonessential-Produced in the body by other amino acids Term Protein-Peptides Definition Short chain of amino acids. Amino Acids are linked by Peptide bonds. Term DNA Definition Contains Genetic Code. Contains sugar Deoxyribose. Nitrogen Base of: Guanine & Adenine Cytosine & Thymine Controls Protein Synthesis. Doubled Stranded (Helix) Term RNA Definition Messenger from nucleus to cytoplasm. Contains sugar Ribose. Nitrogen base of: Guanine & Adenine Cytosine & Uracil Directs protein synthesis. Single Standed Term Cell Definition Has all characteristics of life. Three components: Plasma Membrane Cytoplasm and Organelles Nucleus Term Plasma Membrane Definition Surrounds cell and gives it shape. Formed by double layer of Phosolipds. Selectively permeable The Gate Keeper Term Peripheral Proteins in Plasma Membrane Definition attached to one side only Term Integral Proteins in the Plasma Membrane Definition across the plasma membrane from one side to the other Term Membrane Protein Functions Definition Transport Ezymatic Activity Signal transduction Cell-to-cell recognition Intercellular joining Attachement to cytoskeleton and extracellular matrix Term Glycoproteins Definition Carbohydrates attached to outside of protein in the Plasma Membrane. Affects interaction between cells and Extra-Cellular Environment (ECE) Term Glycolipids Definition Carbohydrates and Lipids attached to outer surface of the Plasma Membrane. Affects interaction between cells and ECE Term Glycolipids Definition Carbohydrates and Lipids attached to outer surface of the Plasma Membrane. Affects interaction between cells and ECE Term Cytoplasm Definition Jelly-like substance between cell membrane and nucleus; suspending medium of orangelles Term Cytoskeleton Definition Network of microfilaments and microtubules providing transportation within cell. Gives cell shape. Railway Term Organelle Definition different structures within a cell that perform a specific function Term Plasma Membrane Definition Membrane composed of two layers of phosolipids and protein molecules. Gives cell form and controls passage in and out. Term Lysosomes Definition Suicide Bag Single-walled sacs of enzymes. Digests foreign molecules and worn cells. Term Mitochondria Definition The Power House. Double-walled vacuoles; energy producing reactions into usable ATP Term Golgi Complex Definition Packaging System. Flattened sacs wtih vacuoles. Synthesizes carbohydrates and packages molecules for secretion. Term Ribosomes Definition Protein synthesis. Granules composed of Ribonucleic acid (RNA) Term Endoplastic Reticulum Definition Provides supporting framework for cells, transports material, protein and lipid synthesis. Smooth: Protein synthesis Rough: Steroid synthesis Term Nucleus Definition Large spherical body composed of the nuclear membrane, nucleolus and chromatin (DNA) Term Vacuoles Definition Large membrous fluid-filled sacs for storage and excretion in cytoplasm Term Perioxisomes Definition Contains Oxidative Enzymes. In the Liver and Kidneys. For detoxification Term RNA Synthesis Definition One Gene-made up of several thousand nucleotide pairs. Codes for one Polypeptide chain. Term Genetic Expression Definition Genetic Transcription: Synthesis of RNA Genetic Translation: Synthesis of Protein Term DNA Replication Definition Replicates itself so identical copies of the Daughter cells match Mother cells Term Cell Death Definition By: Necrosis: pathological changes kill cell Apoptosis: programmed cell death Term Cell Division Definition 1. Mitosis 2. Meoisis Term Mitosis Definition Daughter cells are genetically identical to mother cells. Same # of chromosomes. Grow and repair our tissues. Term Stages of Mitosis Definition Prophase Metaphase Anaphase Telophase Term Interphase Definition phase between succesive divisions Term Prophase Definition Condensed chromosomes are observable. Centioles are moving toward poles of cell. Nuclear membrane starts to disappear Term Metaphase Definition Centromeres (chromatid pairs) attach to spindle fibers. Chromosomes move to equator. Nuclear Membrane disappears. Term Anaphase Definition Sister chromatids of each chromosome separate. Full set (46) move toward each pole, pulled by spindle fibers. Term Telophase Definition Migration to poles is complete. Chromosomes lengthen, nuclei reconstructs, cell division occures. Term Meiosis Definition Daughter cells NOT genetically identical to mother cell. Half o genetic material (single chromosomes) In Gonads and Gametes Sexual Reproduction Term Enzymes Definition Catalysts-increase rate of chemical reactions Usually proteins. Lowers the Activiation Energy required to start a reaction. Term Cofactors Definition Helper for enzymes Metal Ions Term Coenzymes Definition Enzyme Helper Derived from Vitamins. Transports small molecules needed by enzymes. Term Enzyme Activiation Definition Produced in inactive form to protect organ. Activated by phosophorylation. Inactiviated by dephosophorylation. Term Law of Mass Action Definition Direction of reaction is from the side where concentration is higher to side where concentration is lower. Term Metabolic Pathways Definition Substrate -> Intermediates -> Final Products Term Laws of Thermodynamics Definition 1. Energy is neither created nor destroyed. 2. When energy is converted from one form to another, the amount of useful energy decreases. Term Endergonic Reactions Definition Requires input of energy. Products contain more energy than reactants. Makes ATP. Term Exergonic Reactions Definition Releases energy as they proceed. Products contain less energy than reactants. Breaks down ATP Term Coupled Reactions: ATP Definition Coupling Endergonic reactions to Exergonic reactions Term Oxidation Reduction Definition Molecule gains electrons is reduced. Molecule loses elctrons is oxidized. Reducing Agent donates electrons Oxidizing Agent accepts electrons Term Metabolism Definition Converting energy from one form to another Term Glycolysis Definition Breaking down Glucose molecules to 2 pyruvate (no Oxygen-Anaerobic) In Cytoplasm. Energy released: net 2 ATP & 2 NADH Exergonic Term Lactic Acid Pathway Definition NADH from Glycolysis needs to give away H's to continue. No oxygen- H goes to pyruvate creating Lactic Acid (Anaerobic) Oxygen present-H -> O2 forming water (Aerobic) Term Glycogenesis Definition Storage of Glucose as Glycogen-skeletal muscles and liver Term Glycogenolysis Definition Lactic Acid in skeletal muscles goes to Liver. Pyruvate formed -> Glucose -> Glycogen (Cori Cycle) Term Aerobic Respiration Definition In Mitochondra netting 34-36 ATP. Aerobic Glycolysis -> Pyruvate -> into Mitochondra -> Acetyl CoA -> CO2 -> Lungs for secretion Term Krebs Cycle Definition Acetyl CoA and Oxaloacentric combine -> Citrus Acid -> back to Oxaloacentric. Large amount of ATP produced. Term ATP Formation Definition Direct (substrate) phosphorlyation: ATP formed by broken bonds. ATP's in Glycolysis made this way (2 net ATPs Oxidative phosphorylation: ATP generated by Electron Transport Chain. Lots of ATP formed. Term Fats and Protein as Energy Definition Fats hydrolized to Glycerol and Fatty Acids. Proteins -> Amino Acids deanimated for Krebs Term Acetyl CoA Definition Substrate for energy and synthetic pathways. Linked by Fatty Acids (fatty acids + Glycerol = Triglycerides) Adipose and Liver Most energy stored as triglycerides Term Lipolysis Definition Breakdown of lipids into Fatty Acids and Glycerol Term Lipogenesis Definition Formation of Lipids for storage Term Passive Transport Definition Moves compounds down concentration gradient. No Energy. Diffusion, Osmosis, Facilitated Diffusion Term Diffusion Definition Process by which moledules or ions move down from areas of higher concentration to areas of lower concentration. Term Concentration Definition Number of molecules in a given unit of volume Term Gradient Definition Physical difference between two regions Term Osmosis Definition Movement of water from areas of higher concentration to areas of lower concentration to obtain equalibrium. Term Osmotic Pressure Definition Force that would have to be exerted to stop osmosis. The more the concentration of solute, the more the osmotic pressure. Term Solute Definition What you're trying to dissolve Term Solvant Definition What you're using to dissolve solute Term Tonicity Definition Effect of a solution on the Osmotic movement of H2O Term Isotonic Solutions Definition Same solutes. Same osmotic pressure as water. Term Hypertonic Solution Definition High solutes. Higher osmotic pressure than Plasma. Water moves outside cell. Term Hypotonic Solution Definition Low solutes. Lower osmotic pressure than Plasma. Water moves inside cell. Term Facilitated Diffusion Definition Passive transport down concentration gradient by carrier proteins. Term Active Transport Definition Movement against a concentration gradient requiring energy Term Bulk Transport Definition Moving large molecules by Endocytosis, Exocytosis or Phagocytosis Term Endocytosis Definition Cell encloses material Term Exocytosis Definition Cell discharges vacuole-enclosed material Term Phagocytosis Definition Process of body to destroy dead or foreign cells. Macrophages done by exocytosis. Term Nervous System Definition CNS: Brain and spinal cord PND: Cranial and spinal nerves Two types of cells: Neurons Glial Cells Term Neurons Definition Cell Body Dendrites Axons Term Cell Body (Nervous System) Definition Contains nucleus. Makes Macromolcules Processing portion: in CNS: Nuclei in PNS: Ganglia Term Dendrites Definition Receives information. Conducts to cell body Term Axon Definition Conducts away from cell body to the next Neuron or effector Organ. Nerve impulses start at junction called Axon Hillock Term Structural Classification of Neurons Definition Pseudounipolar-cell body sits on side (sensory) Bipolar-Dendrite and Axon are from opposite sides (retinal) Multipolar-many dentrites and one axon (motor) Term Functional Classification of Neurons Definition Sensory/Afferent-impulses into CNS Motor/Efferent-impulses out of CNS Association/Interneurons-integrates activity of Nervous system in CNS Term Glial Cells Definition in both CNS & PNS; supporting cells Term PNS Definition Peripheral Nervous System. Schwann Cells form myelin sheath around Axons. Satellite Cells support neurons in Ganlia. Term CNS Definition Oligodendrocytes: forms Myelin sheath around Axon in CNS. Microglia: phaocytosis Ependymal Cells: lines brain ventricles; produced in CNS. Astrocytes: Blood-Brain Barrier; regulates ECE Term Myelination Definition in PNS each schwann cell myelinates by wrapping around axon. Uninsulated gaps called Nodes of Ranvier Term Astrocytes Definition Most common in Glial cells. Froms Blood-Brain Barrier. Buffers K+ levels. Recycles neurotransmitters. Forms scar tissue. Term Resting Membrane Potential (RMP) Definition Difference in electric charge between inside and outside of cell. Always negatively charge. -70mV Term Ions in cell Definition Na+ more concentrated outside cell (positive). K+ more concentrated inside cell (negative) Term Excitability Definition Ability of some cells to produce and conduct changes in Cell Membrane. Term Depolarization Definition When MP becomes more positive. Occurs by Diffusion. Term Repolarization Definition Membrane Potential returns to RMP. Occurs in Diffusion Term Hyperpolarization Definition MP becomes more negatively charged than RMP. Term Membrane Ion channels Definition Na+ channels: closed in RMP Voltage Gated channels are opened by depolarization K+ channels One channel always open Voltage-Gated, closed in RMP Term Action Potential (AP) Definition Change in the Membrane Potential that travels along the axon from cell body to synapse. Movement of Na+ to inside cell (influx) Movement of K+ to outside of cell (efflux) Term How Stimulus Intensity is Coded Definition Increases stimulus intensity causes more APs to be fired. Size of APs remains constant. Frequency increases. Term Refractory Periods Definition Abosolute: cannot produce another AP because Na+ channels are inactivated. Relative: when K+ channels are open cells needs stronger stimuli; hyperpolarization Term Axonal Conduction (cable properties) Definition Ability of axon to conduct electric current Term Conduction in unmyelinated axons Definition Slow Term Conduction in Myelinated Axons Definition Fast Term Synapse Definition Functional connection between Axon of Neuron (presynaptic) and another cell (postsynaptic). Two types: Chemical and Electrical Term Electrical Synapses Definition Depolarization flows from Presynaptic to Postsynaptic cell through channels called Gap Junctions. In: Smooth and Cardiac Muscles, Brain (rare) and Glial Cells Term Chemical Synapses (most common) Definition Synaptic cleft separates Terminal Bouton of pre and postsynaptic cell. NT are in Synaptic Vesicles. Vesicles fuse with Bouton Membrane and release NT by Exocytosis. Amount of NT released depends on Frequency of APs. Term Gap Junctions Definition Formed by Connexin Proteins Term Synaptic Transmission Definition Opens VG Ca2 channels in Bouton. Ca2 driven by Eletrochemical gradient: 1) triggers Exocytosis of vesicles 2) release of NT into Synaptic Clefts. NT (ligand) diffuse across the cleft; binds to protein receptors on postsynaptic membrane. Chemically-regulated ion channels open. Depolarization-EPSP Hyperpolarization-IPSP Term EPSP (Excitatory Postsynaptic Potentials) Definition stimulates the postsynaptic cell to produce Term IPSP (Inhibitory Postsynaptic Potentials) Definition antagonizes the formation of AP in the Postsynaptic cell Term Acetylcholine (ACh) Definition NT at all Neuromuscular Junctions. Used in Brain and ANS. Can be Excititory or Inhibitory based on receptor; subtype: Nicotinic and Muscarinic Term Nicotinic ACh Channels Definition Found in brain, autonomic ganglia and skeletal muscles. Diffusion of Na+ into and K+ out of Postsynaptic cell causing depolarization. Produces EPSP. Term Muscarinic ACh Channel Definition Smooth Muscle. Binding of one activates G-protein receptor; opens some K+ channels-hyperpolarization; closes others-depolarization. Can be Excititory or Inhibitory Term Neuromuscular Junction (NMJ) Definition Cholinergic Neurons use ACh as NT. On Skeletal Muscles called End Plates or NMJ; opens VG channels-depolarization; causes muscle contraction. Curare blocks ACh at NMJ Term Monoanime NTs Definition Includes Serotonin, Norepinephrine and Dopamine. Serotonin from Tryptophan. Norepinephrine and Dopamine from Tyrosine called CATECHOLAMINES. After released are mostly inactivated by: Presynaptic Reuptake. Breakdown by: Monoamine Oxidase (MAO) and Caltecco Methyltransferase (COMT). Antidepressants. Term Serotonin Definition Mood, Behavior, Appetite and Cerebral circulation. SSRI-serotonin-specific reuptake inhibitor) Term Dopamine Definition Motor Control and Emotional Reward. Parkinsons, Addiction and Schizophrenia Term Norepinephrine Definition Used in PNS and CNS. In PNS-Sympathetic NT. In CNS-affects general level of arousal such as Amphetamines. Term Amino Acid NTs Definition Gluaic acid and Aspartic acid are major CNS excitatory NTs. Glycine is inhibitory NT: opens CI-channels causing hyperpolarization; strychnine blocks Glycine receptors. GABA-most common in brain; Inhibitory - opens CI- channels Term Polypeptide NTs (Neuropeptides) Definition Many are Neuromodulators- learning and Neural plasticity. Neuropeptide Y is the most common: Appetite Stimulator. Endocannabinoids: like THC; only lipid NT; Analgesic Effect. Nitric Oxide and Carbon Monoxide: Gas NT; Nitric Oxide causes smooth muscle relaxation. Cholestokinin-Satiety. Endorphins-Exercise enduced Euphoria; blocked by Naloxome-an opiate antagonist Term EPSPs (differences from AP) Definition Graded in Magnitude. Have no threshold. Causes depolarization. Summate. Have no Refractory period. Term Spatial Summation Definition Takes place when EPSPs from different synapes occur in postsynaptic cell at the same time. Term Temporal Summation Definition Successive release of NTs from presynaptic Axon terminal causes summation of EPSPs in postsynaptic Neuron. Depends of the Requency of APs. Term Synaptic Plasticity Definition Repeated use of a synapse can increase od decrease its strength of transmission: a) Sympathetic Facilitation b) Sympathetic Depression. High Frequency Stimulation enhances excitability. Long term potential-Learning and Memory Term Synaptic Inhibition Definition Postsynaptic Inhibition: GABA and Glycine produces IPSP; Antagonizes EPSPs making it harder to reach threshold. Presynaptic inhibition: amount of NT at synapse decreases; one neuron synapes onto axon or boulton of another neuron inhibiting release of NT. Term Nucleus (Nervous System) Definition Collection of Neuron Body cells in CNS. "Center" Term Ganglion (Nervous System) Definition Collection of Neuron Cell bodies in PNS Term Tract (Nervous System) Definition Bundle of Axons in CNS. Large tract is called column. Term Nerve (Nervous System) Definition Bundle of Axons in PNS Term Sensory Neurons (CNS) Definition Controls all body activities by RECEIVING sensory information Term Motor Neurons (CNS) Definition DIRECTS 9sends out) activity of the body Term Association Neurons (CNS) Definition Integrates sensory and motor activity; Only in CNS Term Gray Matter (CNS) Definition Consists of Neuron Bodies and Dendrites. Processing. Term White Matter (CNS) Definition Consists of Axon tracts. Myelin Carries information Term Cerebrum Definition Largest part of brain. Two Hemisphere. Higher Mental Functions. Five lobes: Frontal, Parietal, Temporal, Occipital, Insula Term Cerebral Cortex Definition Outer layer of Cerebrum. Gray Matter. Gyrus and Sulcus. Term Frontal Lobe Definition Motor Control Term Parietal Lobe Definition Sensory Term Temporal Lobe Definition Auditory Term Occipital Lobe Definition Vision Term Insula Definition Memory Encoding Term EEG Definition Measures Electrical activity of cerbral cortex. Diagnoses Epilepsy and Brain Death Term CT Definition visualizes soft tissue Term MRI Definition shows brain function Term PET Definition examines Brain Metabolism and Blood Flow. Term Four Waves of EEG Definition Alpha, Beta, Theta, Delta Term Alpha Waves (EEG) Definition Records from Parietal and Occipital lobes. Awake, relaxed, eyes closed. Term Beta Definition Strongest in Frontal lobe. Visually stimulated and mental activity. Term Theta Definition From Temporal and Occipital lobes. During sleep. In adults indicates severe Emotional Stress. Term Delta Definition From Cerbral Cortex. Adult asleep; awake infants. In awake adults indicates brain damage. Term Basal Nuclei Definition Distinct masses of Cell Bodies deep inside cerebrum. Control of VOLUNTARY MOVEMENT. Term Left Hemisphere Definition Language. Analytical Abilities. Term Right Hemisphere Definition Visuospatial Tasks. Can recognize things but not describe them. Term Broca's Area Definition Necessary for articulation of speech. Patient can understand but not repeat. Speech is slow. Term Wemicke's area Definition Language Comprehension: can't understand spoken or written language. WORD SALAD. Term Hippocampus (Memory) Definition Critical for acquiring new memories and consolidating short into long-term memory. Term Amygdala Definition Part of Limbic System. Crucial for fear memories. Term Memory Definition STORAGE of memory is in the Cerebral Hemispheres. Higher order processing and planning occure in Prefrontal Cortex. Term Neurogenesis in Hippocampus Definition Crucial for Learning and Memory. Contains Neural Stem Cells that continually produce new Neurons. Stress and Depression cause Hippocampus to shrink. Term Diencephalon Definition Part of forebrain. Two parts: Thalamus and Epithalamus; Hypothalamus Term Thalamus Definition Relay Center through which all sensory information (except olfactory) passes to cerebrum. Term Epithalamus Definition Contains Choroid Plexus which creates CSF. Also contains Pineal Gland which produces Melatonin for our sleep cycles. Term Hypothalamus Definition Link between Nervous and Endocrine System. MOST IMPORTANT structure for Homeostasis. Hunger, thirst, body temp, sleep, sexual arousal, anger, fear, pain, pleasure, hormone from Anterior Pituitary, Sympathetic and parasympathetic. Term Pituitary Gland Definition Anterior and Posterior lobes. Posterior stores and releases ADH and Oxytocin. Hypothalamus controls Anterior Pituitary Term Circadian Rhythms Definition Body's Daily Rhythms. Regulated by SCN of Hypothalamus. Master Clock. Adjusted by light. Controls Pineal Gland. Term Midbrain Definition RELAY CENTER for motor and sensory pathways. Control of skeletal muscles and movement. Contains: a) Superior Colliculi-visual b) Ingerior Colliculi-auditory. Below the Hypothalamus. Term Hindbrain Definition COORDINATION OF MOVEMENTS and Motor Learning. Pons. Cerebellum. Medulla Oblongata. Term Pons Definition Apneustic and Pneumotaxic centers for regulation of respiration Term Cerebellum Definition Coordination of movements Term Medulla Oblongata Definition Three Vital Centers: Respiratory, Cardiac, Vasomotor Term Spinal Cord Definition Gray Matter-Neuron cell Bodies; H-shaped; Anterior and Posterior Horns. White Matter-Axons. Ascending and Descending tracts. Term Ascending Spinal Tracts Definition Sensory to opposite side of body Term Descending Spinal Tracts Definition Motor. Two Groups: Pyrmidal or Corticospinal for FINE motor skills. Extrapyrmidal which influences movement indirectly. Term Peripheral Nervous System (PNS) Definition Nerves-exit brain and spinal cord. Ganglia (group of cell bodies in PNS) Term Crainial Nerves Definition 12 pairs. Exit Brain. Most Mixed Nerves. Term I. Olfactory Definition Smell Term II. Optic Definition Vision Term V. Trigeminal Definition Chewing. Face and Mouth touch and pain. Term VII. Facial Definition Controls most facial expressions. Secretion of saliva and tears. Taste. Term X. Vagus Definition Senses aortic blood pressure. Slows heart rate. Stimulates digestive organs. Taste. Term Spinal Nerves Definition All Mixed Nerves into spinal cord. Dorsal/Posterior root-Sensory. Ventral/Anterior root-Motor Term Breakdown of Spinal Nerves Definition 8 Cervical. 12 Thoracic. 5 Lumbar. 5 Sacral. 1 Coccygeal. Term Reflex Arc Definition Simple sensory input, motor output circuit. Not involving the brain. Term The Autonomic Nervous System Definition Controls organs not under voluntary control. Manages: Cardiac, Smooth, Glands. Many smooth muscles are under intrinsic control without ANS input. ANS effect is to increase or decrease the intrinsic activity. Term Autonomic Neurons Definition Two Neurons in Efferent (motor) Pathways: 1) Preganglionic-cell body in CNS 2) Postganglionic-cell body in Autonomic Ganglion. Postganglionic Axon extends from Autonomic Ganglion to Target Tissue. Term Division of ANS Definition Sympathetic and Parasympathetic. Usually antagonistic. They coordinate physiology according to the situation. Term Sympathetic Division Definition "Fight or Flight, Stress reactions" AKA Thoracolumbar Division. Preganlionic exits spinal cord from T1 to L2. Synapes with postganglionic neurons in paravertebral ganglion which forms chain of interconnecting ganglia parallel to spinal cord. Characterized by Divergence and Convergence. This causes the Sympathic division to act as one unit (Mass Activation) Term Sympathoadrenal System Definition Works with Sympathetic Division. Adrenal Medulla; Secretory cells appear to be modified Postganglionic Neurons. RELEASES 85% Epinepherine and 15% norepherine. Stimulated by Mass Activiation. Term Parasympathetic Division Definition "Rest and Digest" AKA Craniosacral Division-long preganglionic fibers originate in Midbrain, Medulla Oblangata, Pons and S3 - S4. Synapse in Termianl Ganglica is next to or within Target Organ. Postganglionic have short axons. Long Vaguys Nerve (X Cranial) mostly parasympathetic fibers; innervates heart, lungs, esophogus, stomach, pancreas, liver, small intestine, upper half large intestine. Preganglionic fibers (S2 - S4) innvervate lower half of large intestines, rectum, urinary and reproductive Term ANS Neurotransmittersq Definition released in both Sympathetic and Parasympathetic preganglions->releases ACh @ all NMJ. Parasympathetic postganglions also release ACh called Cholinergic synapses. Most Sympathetic Postganglions release Norephinepherine called Adrenergic Term Cholinergic Stimulation Definition ACh is used at: all motor synapses on skeletal muscles; all preganglionics; parasympathetic postganglionics. Two types of receptors: Nicotinic and Muscarinic Term Adrenergic Stimulation Definition causes both Excitation and Inhibition Term Organs with Dual Innervation Definition Organs supplied by both Sympathetic and Parasympathetic. Effects are Anatagonistic, Complimentary and Cooperative. Term Organs without Dual Innervation Definition Only Sympathetic Innervation: Adrenal medulla, Arrector Pili Muscle, Sweat Glands and most blood vessels. Term Medulla Definition Most directly controls activity of ANS. Center for control of Cardiovascular, Pulmonary, Urinary, Reproductive and Digestive Term Hypothalamus Definition center for control of body temp, hunger and thirst. Can also regulate medulla. Term Limbic System Definition responsible for Visceral Responses that effect Emotional state. Cerebral Cortex and Cerebellum also influence ANS. Term Structure of Eye Definition Three layers: 1) Sclera-Cornea 2) Choroid 3) Retina. Also: Iris, Lens, Ciliary Muscles, Optic Nerve. Anterior-Watery fluid (Aquenus Humor) Posterior-Jelly-kije (Vitreous Humor) Term Choroid Definition Blood vessels Term Sclera Definition Outer white fibrous tissue. Cornea: Anterior part; clear and transparent. Term Retina Definition Photoreceptors: Cones and Rods. Optic Disc: axons of retinal neurons gather and then exit optic nerve. Light Receptors. Term Iris Definition Gives color and controls amount of light; pigmented muscle tissue. Pupil: opening in the middle of Iris. Two muscles: 1) Circular (parasympathetic) constricts 2) Radial (Sympathetic)dialates Term Lens Definition the focus image on the retina Term Ciliary Muscle Definition changes power of lens Term Optic Nerve Definition carries visual impulses to brain. Axons of retinal neurons exit eye at optic nerve. Term Pathway of Light Definition Cornea -> Anterior chamber -> Pupil -> Lens -> Vitreous Humor -> Retina Term Accomadation Definition Ability of eyes to keep image focused on retina as the distance between eyes and object varies. Results in contraction of ciliary muscles: > 20 feet causes ciliary relaxation, lens flat, least convex; < 20 feet ciliary muscles contract, reducing tension, more convex. Term Myopia Definition Nearsighted. Correctd with concave lense. Term Hyperopia Definition Farsighted. Corrected with convex lens. Term Astigmatism Definition Inability to focus images. Corrected by Cylindrical lens. Term Presbyopia Definition Loss of accomadation (aging usually) Corrected with convex lens-reading glasses. Term Skeletal Muscles Definition Attached to bones at Origin (fixed point) and Insertion (movable point). When muscle contracts it becomes shorter and pulls on tendon to move bone at joint. Groups: Flexors decrease angle and Extensors increase angle. Antagonistic: 2 muscles-opposite actions. Term Skeletal Muscle Structure Definition Three layers of connective tissue: 1) Epimysium-surrounds whole muscle; continuous with tendon 2) Permysium-surrounds bundles (fascicles) of muscle fibers 3) Endomysium-covers indiviual muscles fibers. Epi and Permysium contain blood vessels and nerves. Term Muscle Fibers Definition Muscle fibers are muscle cells. Multinucleated. Plasma Membrane called Sarcolemma. Cytoplasm called Sarcoplam. ER is called Sarcoplasmic Reticulum. Rich in Mitochondria. Skeletal muscles are striated. Term Structure of Muscle Fiber Definition Each fiber is packed with myofibrils. Myofibrils extend length of fiber. Myofibrils packed with myofilamints (thick are Myosin and thin are Actin). Gives rise to bands that cause striations. Term Structures of Myofibril Definition A Bands are dark bands with myosin and actin. H zone is the light area at center of A Band where myosin and actin don't overlap. I Bands are light bands with actin only; Z line/disc is at the center of the I Bands where actin attaches. Term A Bands Definition Dark bands with light area in the middle called H zone. Contains Myosin and Actin. Term H zone Definition Light area at center of A Band. Area where Actin and myosin don't overlap. Term I Band Definition Light and contains only Actin Term Z line/disc Definition Center of I Band where Actin attaches Term Sarcomeres Definition Contractile (functional) unites of skeletal muscles between two Z lines. M lines: structural proteins that anchor myosin during contraction. Titan: elastic protein attaching myosin to Z disc that contributes to elastic recoil of muscle. Term Neuromuscular Junction (NMJ) Definition Where Nervous System meets muscle. Neuromuscular Junction: where branch of Axon meets Sarcolemma of muscle fiber. Motor End Plate: place on sarcolemma where NJ occurs. Term Motor Unit Definition Formed of a Motor Neuron and all muscle fibers it innervates. When motor neuron is activated ALL muscle fibers in its Motor Unit contract. Fine control occurs when motor units are small. Recruitment Term Recruitment Definition Brain estimates # of motor units required and stimulates them to contract. Continues till desired movement accomplished in smooth fashion. More and larger motor unites to produce greater strength. Term Sliding Filament Theory of Contraction Definition Muscles contract when Thin Filaments slide over and between Thick Filaments towards center. Leads to shortening of sarcomeres (distnace from Z to Z). I bands (thin filaments) and H bands (thick filaments) become shorter. Length of each filament stays the same. A Band stays the same. Term Excitation-Contraction Coupling Definition Release of ACh and NMJ causes large depolarizing end-plate and APs in muscle fibers. Ca++ channels in SR mechanically linked to T Tubules. APs in T Tubules cause release of Ca++ from cisternae via VG Ca++ release channels. CALLED Electromechanical Release. Term Muscle Relaxation Definition When APs cease, muscle relaxes. Cause: Ca++ channels close; Ca++ pumped back into SR. Term Twitch Definition A single, rapid contraction and relaxation of muscle fibers. Term Summation Definition If 2nd stimulus occurs before muscle relaxes from 1st stimulus, 2nd twitch will be greater. Term Graded Contractionss Definition Contractions of varying strengths. Obtained by stimulation of varying numbers of fibers. Term Tetanus Definition Incomplete Tetanus: If muscle is stimulated by an increasing frequency of electrical shocks, its tension will increase to a maximum. Complete Tetanus: If frequency is so fast NO RELAXATION occures and a smooth sustained contraction occurs. Term Isotonic Contraction Definition Forces remain constant throughout shortening process Term Isometric Contraction Definition Exerted force does not cause load to move and length of fibers remain constant. Term Eccentric Contraction Definition Muscle becomes larger. Load is greater than exerted force. Fibers lengthen. Term Length-Tension Relationship Definition Strength of muscle contraction influenced by: Frequency of stimulation; Thickness of each muscle fiber; Initial length of muscle fiber. The longer the initial length , the stronger the contraction. Term Metabolism of Skeletal Muscles Definition Skeletal Muscles respire Anaerobically the 1st 45 - 90 seconds; the Cardiopulmonary system requires this time to increase o2 for exercising muscles. Aerobic Exercise contributes the majority of muscle requirements after 2 minutes. More ATP's and CO2 AND H2O end product. Term Maximum Oxygen Uptake Definition Aerobic Capacity determined by age, gender and size. Lactate (Anaerobic) Threshold: significant rise in blood lactate levels; healthy individuals this is at 50 - 70% of Max Oxygen uptake. Term Oxygen Debt Definition When exercise stops, rate of oxygen uptake does not return immediately to pre exercise levels. Oxygen is drawn from Hemoglobin and Myoglobin during exercise because ox is needed for metabolism of Lactic Acid produced by Anaerobic Respiration-Cori Cycle. Term Type of Skeletal Muscles Definition Slow-Twitch (slow fatigue) Type I fibers; Fast-Twitch (fast fatigue) Type IIA and IIX fibers Term Type I Fibers Definition AKA Red Slow Oxidative (Aerobic Respiration) Has Mitochondria and Aerobic enzymes. Lots of myoglobin (O2 storage molecule). Gives fibers red color. Small motor neurons with small motor units. Rich Capillary supply. Term Type II Fibers Definition Type IIX: AKA White Fast Glycolyte; Anaerobic Repiration. Large stores of glyogen, few capillaries and few mitochondria, little myoglobin. Type IIA: AKA White Fast Oxidative. Contracts fast using Aerobic Metabolism. Intermediate to Type I and IIX. Large motor neurons with large motor units Term Muscle Fatigue Definition Sustained muscle contraction is due to accumulation of extracellular K+ Term Neural Control of Skeletal Muscles Definition Lower Motor Neurons: motor neuon cells bodies are in Ventral Horn of spinal cord; axons leave in Ventral Root. Activity influenced by sensory feedback from muscles and tendons. Facilitory and Inhibitory activity from Upper Motor Neurons. Term Monosynaptic-Stretch Reflex Definition consists of only one synapse within CNS ex. knee-jerk reflex Term Golgi Tendon Organ Reflex Definition Disynaptic Reflex: 2 synapses in CNS. Sensory axons from Golgi tendon organ synapse with interneurons (in CNS only) Prevents excessive muscle contractions or excessive passive muscle stretching Term Cross-Extensor Reflex Definition Double Reciprocal Innervation. Affecting muscles on contralateral side of spinal cord. Term Upper Motor Neuron Control of Skeletal Muscles Definition Influences lower motor neurons. Axons of neurons in Precentral Gyrus form Pyramidal Tracts. Extrapymidal Tracts arise from neurons in other areas of the brain. Cerebellum-all oupute aids Motor Coordination. Baseal Ganlia (nuclei) exerts inhibitory effects on activity of Lower Motor neurons. Term Cardiac Muscle Definition Stiated and involuntary. Myocaridal cells joine by intercalated discs allowing APs to spread throughout cardiac muscle. Term Smooth Muscle Definition No sarcomeres. Gap Junctions. 16 x more actin than myosin allowing greater stretching and contracting. Actin filaments are anchored to dense bodies.