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Details Title: KINE 2011 Description: Human Physio 1 Total Flash Cards: 52 Created: 12/02/2007 08:12:32	To study from this set of flash cards, or to create your own your own study flash cards, register HERE. If you are already a registered user, CLICK HERE.
Cards Term Homeostasis Definition Dynamic mechanisms that detect and respond to deviations in physiology variables from their "set point" values by initiating effector responses that restore the variables to the optimal physiological range Term Endocrine signal Definition Singal reaches target after transport in blood Term Paracrine signal Definition signal reaches neighbouring cells via the interstitial fluid Term Autocrine signal Definition signal affects the cell that syntesized the signal (acts on itself) Term 4 characteristics of cell membrane Definition selective barrier detect extracellular signal linkage to other cells anchor to extracellular matrix Term Integral Protein Definition amphipathic, many are transmembrane, form important structures Term Peripheral protein Definition attached to integral proteins usually on cytoplasmic side, not amphipathic, often attach to cytoskeleton of cell Term Glycoproteins Definition small amount of saccharides attached to intergral proteins, identify and interact with neighbouring cells, fuzzy coat (glycocalyx) Term Desosomes (Desmosomes) Definition junction that holds two cells together consists of plasma membranes of adjacent cells linked by fibres holds adjacent cells firmly together in areas that are subject to considerable stretching, such as skin molecules can pass through Term Tight junctions Definition extracellular surfaces of two adjacent plasma membranes join together so that no extra cellullar space remains between them occurs in a band around the entire circumference of the cell e.g. epithelial cells, which covers the inner surface of the intestinal tract allows selective barrier properties to control molecules which passes through Term Gap junctions Definition protein channels linking the cytosols of adjacent cells e.g. heart muscle cells Term Rough ER Definition flattened sacs, have attached ribosomes for protein synthesis and packaging Term Smooth ER and Sarcoplasmic Recticulum Definition more tubular in shape than Rough ER, lipid synthesis and Ca2+ storage/release Sarcoplasmic recticulum - specialized arean of Smooth ER regulating Ca2+ Term Golgi Apparatus Definition concentrates, modifies and sorts proteins arriving from the Rough ER prior to their distribution by way of golgi vesicles (aka budding), to other organelles or to secretion from the cell (aka exocytosis) Term lysosome & peroxisome Definition organelle containing digestive enzymes in a highly acid solution that break down bacteria, large molecules, and damaged components of cells peroxisome works with lysosome in the degradation of intracellular debris Term Mitochondria Definition site of ATP production, O2 utilization, and CO2 formation. Contains enzymes active in Krebs cycle and oxidative phosphorylation. Provides 95% of ATP for the cell Term Cytochrome Definition one of a series of enzymes that couples energy to ATP formation during oxidative phosphorylation (ETC) has a red pigment due to the presence of iron containing Heme iron deficient diet: decreased cytochrome synthesis -> decrease endurance; decrease in hemoglobin synthesis -> anemia Term 4 Purposes of Cytoskeleton 3 types of Cytoskeletal filaments Definition maintain cell structure produce cell movement provide structure for cell division provide attachment surfaces for plasma membrane, enzymes and receptors filaments microfilaments: small, made of actin protein, for structure intermediate filaments: intermediate, e.g. found in desosomes microtubule: large, made of tubulin, e.g. used in cell division Term 3 steps modifying primary RNA to mRNA Definition capping: methylguanylate is added at the start of the primary RNA transcript; helps prevent RNA degradation by RNAse polyadenylation: string of adenines (aka poly A-tail) added to the end of the primary RNA trnascript splicing: introns are removed from primary RNA and the exons are spliced back together; splicing doen by spliceosomes Term Promoter regions Definition specific sequence of nucleotides (found between genes) where the RNA polymerase binds controls the initiation of gene transcription determines which of the paired strands of DNA is transcribed into RNA TATA box? Term Transcription factors Definition proteins that bind in the upstream of the region of the gene, i.e. promoter region help or hinder binding of RNA polymerase regulates gene transcription many TF can act on a single promoter region. the overall "sum" of TF decides whether a gene will be transcribed or not have distinct sequnce of nucleotides they prefer to bind to single TF can act on several promoter regions activated by intra/extracellular signals, i.e. hormones Term 3 stages to RNA translation Definition INITIATION - tRNA will identify and bind to start codon (usually only Met can enter the P-site directly without peptide chain); slowest step ELONGATION - all reactions after first amino acid added until termination of codon; fastest step TERMINATION - steps needed to release peptide chain and ribosome from mRNA Term Ubiquitin Definition small signaling peptide attached to proteins destined to be degraded tagged by ubiquitin ligase signals the proteasome to cleave the protein into small peptides Term Factors affecting protein binding Definition specificity affinity competition saturation Term Glycolysis Definition Net reaction   input: glucose, 2 ADP, 2 Pi, 2 NAD+ output: 2 pyruvate, 2 ATP, 2 NADH + 2 H+, 2 H2O Term Kreb's Cycle Definition Net reaction input: Acetyl CoA + 3 NAD + FAD + GDP + Pi + 2 H2O   output: 2 CO2 + CoA + 3 NADH + 3H+ + 2 FADH2 + GTP Term Oxydative Phosphorylation Definition Net reaction   Input:  0.5 O2 + NADH + H+ + 3 ADP + 3 Pi   Output: H2O + NAD+ + 3ATP   chemiosmotic hypothesis: proposed mechanism by which ATP is formed during oxydative phosphorylation; the hypothesis proposes that the movement of protons across mitochondrial inner membranes is coupled with ATP production Term Oxidative deamination Transamination Definition Oxidative deamination - converting amino acid to keto and coenzyme (e.g. glutamic acid to keto acid)   Transamination - converting amino acid to another amino acid (e.g. keto + alanine --> glutamic + pyruvate) Term Lypolysis Definition breakdown of lipids into glycerol and fatty acids for fuel glycerol -> glycerol-3-phosphate -> DHAP (glycolysis) Fat acid -> beta-oxidation; each turn produces 1 NADH and 1 FADH2 Term Fatty Acid Synthesis Definition occurs in the cytosol linking of Acetyl CoA molecules together to form fatty acid chains (2 carbons at a time) 3 fatty acid chains + glycerol = triglyceride Acetyl CoA cannot be used to make sugar (e.g. pyruvate to ACoA is irreversible); adipocytes lack glycerol kinase Term Gluconeogenesis Definition formation of glucose (during fasting) by the liver or kidneys from pyruvate, lactate, glycerol or amino acids (not carbohydrate) Term Active Transports Definition primary transport: requires energy to move molecules against gradient secondary transport: requires indirect energy antiport: use energy from one type of  molecule moving with gradient to move another type of molecule against gradient symport: use energy from one type of molecule moving with gradient to move another type of molecule with gradient Term Kinase vs Phosphatase vs Phosphorylase Definition Kinase: transfer phosphate group from a donor to a substrate   Phosphatases: remove a phosphate group from a substrate   Phosphorylases: add a phosphate group from an inorganic phosphate to a substrate Term Neurotransmitter vs Hormone vs Paracrine Agent Definition Neurotransmitter: only released by neurons Hormone: released by endocrine cells, acts on target cells Paracrine agent: chemical messenger that effects nearby cells Term Competition vs Agonist vs Antagonist Definition competition: the ability of different molecules very similar in structure to compete with each other to combine with the same receptor antagonist: a molecule that competes for a receptor with a chemical messenger normally present in the body. The antagonist binds to the receptor but does not trigger the cell's response agonist: a chemical messenger that binds to a receptor and triggers the cell's response; often refers to a drug that mimics a normal messenger's action Term receptor activation Definition combining ot messenger with receptor causing a change in teh conformation of the receptor 5 types of responses permeability, transport properties, or electrical state of the cell's plasma mebrane cell's metabolism cell's secretory activity cell's rate of proliferation and differentiation cell's contractile activity Term Second messengers Definition - substances that enter or are generated in the cytoplasm as a result of receptor activation by the first messenger. The second messengers diffuse througout the cell to serve as chemical relays from the plasma membrane to the biochemical machinery inside the cell Term Three Classes of Hormones Definition Amine hormones (nitrogen base) derivatives of tyrosine incl. thyroid (lipid soluble) and catecholamines (nor/epi and dopamine, water soluble, released from adenal medulla) Peptide hormones (lipid insoluble) majority of hormones preprohormone (zymogens), cleave to be activated packaging by rough ER and Golgi before being released into ECF and then blood Steroid hormones (lipid soluble) produced by adrenal cortex (metabolism and stress) and gonads Term Tropic Hormone Definition hormone effecting release of other hormone, either inhibit or effect Term Removal of Hormone Definition majority removed by liver and kidney; water soluble hormones are removed more quickly Term Blood Glucose Homeostasis Definition Homeostatic range 4-7 (optimal)   Hypoglycemic action: lowering of sugar level; insulin (promotes glucose transporters to membrane), biphasic   Hypoglycemia early symptoms: anxiety, shakiness, weakness, nausea   Hypoglycemia prolonged symptoms: confusion, hallucinations, coma   Hyperglycemic action: increasing sugar level; glucagon, epinephrin, cortisol, growth hormone   Hyperglycemia early symptoms: polyuria (excessive urination), polydipsia (frequent thirst), altered vision   Hyperglycemia prolonged symptoms: hyperventilation, hypotension, cardiac arrythmias, diabetes   Levels of insulin increased by glucose level, amino acids, glucose-dependent insulinotropic peptide (GIP), rest and digest. Levels of insulin decreased by epinephrine     Term Islets of Langerhans Definition In pancreas produces glucagon, insulin, somatostatin (inhibits growth hormone, inhibits release of insulin and glucagon) Term Pituitary gland Definition anterior aka adenohypophysis posterior aka neurohypophysis Term Posterior Pituitary Definition neural extension of hypothalamus releases oxytocin: stimulate breast milk secretion and uterine contraction vasopressin: ADH, decrease water loss increase blood pressure Term Calcium Homeostasis Definition bone growth maintenance muscle contraction cellular signaling blood coagulation hypocalcemia: @ 50% spasms and tetany, <40% lethal hypercalcemia: 20-50% above normal depressed nervous system and altered heart rate; above 70% normal precipitation -> lethal regulated by endocrine system parathyroid hormone and calcitriol (vita D) increase Ca calcitonin decrease Ca, suppress osteoclast, antagonist of parathyroid Term Bone cells Definition osteoid: collagen matrix osteoblast: secrete collagen matrix, where Ca and PO4 is deposited osteocyte: differentiated osteoblast osteoclast: catabolize bone to make Ca for resorption into ECF Turnover 100%/year in infants 15%/year in adults 5%/year in senior Term Osteoporosis Definition bone disease in which bone resoprtion exceeds bone deposition aging and decrease in compression stress greatest factors structural integrity of trabecular bone is impaired. cortical bone becomes more porous and thinner increased incidence of fractures Term Glial Cells Definition oligodendrocyte/schwann cells - form myelin   astrocyte - K+ regulation, remove waste products, provide glucose, provide optimal environment for neurons, directs axon connections   microglial - scaveng debris Term 3 factors to resting membrane potential Definition Na/K ATPase is electrogenic presense of non penetrating negtive charges inside cell (i.e. protein, AA) membrane is more permeable to K+ than Na+ Term AP at neuromuscular junction Definition AP moves down axon Activates Ca2+ channel influx of Ca2+ releaese neurotransmitter into synapse NT binds to Na channel receptors Term Refractory Period Definition absolute: repolarizing period, when membrane cannot have another AP relative: following the absolute refractory period, stimulus needs to be stronger due to hyperpolarization Term Definition