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| 5549586752 | signal transduction pathway | The process by which a signal on a cell's surface is converted into a specific cellular response | 0 | |
| 5549586753 | local regulators | messenger molecules that travel a short distance, an example of this is growth factors | 1 | |
| 5549586754 | paracrine signaling | A secreting cell acts on nearby target cells by discharging molecules of a local regulator into the extracellular fluid. |  | 2 |
| 5549586755 | synaptic signaling | a nerve cell releases neurotransmitter molecules into a synapse, stimulating the target cell |  | 3 |
| 5549586756 | Local signaling | signaling between adjacent cells (paracrine, autocrine, and synaptic) | 4 | |
| 5549586757 | hormones | chemicals used for long distance signaling | 5 | |
| 5549586758 | Long distance signaling |  | 6 | |
| 5549586759 | hormonal signaling | specialized endocrine cells secrete hormones into body fluids often the blood. Hormones reach virtually all body cells | 7 | |
| 5549586760 | reception | the target cell's detection of a signal molecule coming from outside the cell. The chemical signal is detected when it binds to a receptor protein. |  | 8 |
| 5549586761 | transduction | The binding of a signal protein changes the receptor protein in some way, intiating this process. This stage converts the signal into a form that can bring about a specific cellular response. | 9 | |
| 5549586762 | response | the result of transduction is a specific response for example the shutting on or off of a gene. | 10 | |
| 5549586763 | ligand | a molecule that specifically binds to another often larger molecule. the binding of this often causes a receptor portion to under go w change in conformation i.e. shape. | 11 | |
| 5549586764 | G-protein-linked receptor | a plasma membrane receptor that works with the help of a protein called a g-protein | 12 | |
| 5549586765 | receptor tyrosine kinase | can trigger more than one signal transduction pathway at once, helping regulate and coordinate many aspects of cell growth and cell reproduction. This receptor is a major class of plasma membrane receptors charcterized by having enzymatic activity. | 13 | |
| 5549586766 | Kianse | an enzyme that catalyzes the transfer of phosphate groups. | 14 | |
| 5549586767 | Dimer | the formation that results when two receptor polypetitdes receive a signal molecule causing the two to associate closely with each other. Dimerization activates the tyrosine-kinase region of each polypeptide. | 15 | |
| 5549586768 | protein kianse | general name for an enzyme that transfers phosphate groups from ATP to a protein. | 16 | |
| 5549586769 | Phosphorylation cascade | a series of different molecules in a pathway are phosphorylated in turn , each molecule adding a phosphate group to the next one in a line . |  | 17 |
| 5549586770 | protein phosphates | enzymes that rapidly remove phosphate groups from proteins, a process called dephosphorylation | 18 | |
| 5549586771 | second messengers | non-protein, small, water soluble molecules or ions, spread through the cell by diffusion | 19 | |
| 5549586772 | cyclic AMP or cAMP | An enzyme embedded in the plasma membrane, is made from ATP by adenylyl cyclase inactivated by phosphodiesterase an enzyme that converts it to AMP | 20 | |
| 5549586773 | inositol triphosphate( IP3) | A second messenger that functions as an intermediate between certain nonsteroid hormones and a third messenger, a rise in cytoplasmic Ca 2+ concentration. | 21 | |
| 5549586774 | diacylglycerol (DAG) | activates a class of protein kinases known as protein kinase C, which phosphorylate other proteins and cause a cell response, a second messenger | 22 | |
| 5549586775 | scaffolding proteins | large relay proteins to which several other rely proteins are simultaneously attached |  | 23 |
| 5549586776 | evolution of cell signaling | signaling on microbes had much in common with processes in multicellular organisms, suggesting an early origin of signaling mechanisms | 24 | |
| 5549586777 | binding of signal molecule | binding to a receptor is highly specific. A conformational change in a receptor is often the initial transduction of the signal. | 25 | |
| 5549586778 | Intracellular Receptors | cytoplasmic or nuclear proteins. Signal molecules that are small or hydrophobic and can readily cross the plasma membrane use these receptors | 26 | |
| 5549586779 | Signal transduction pathways | At each step in a pathway, the signal is transducer into a different form, commonly a conformational change in a protein. | 27 | |
| 5549586780 | endocrine system | the internal system of chemical cmmunicationinvolving hormones, the ductless glands that secrete hormones; functions in concert with the nervous system effect internal regulation and maintain homeostasis. | 28 | |
| 5549586781 | endocrine gland | a ductless gland that secretes hormones directly into the interstitial fluid, from which they diffuse into the bloodstream | 29 | |
| 5549586782 | endocrine signaling | Secrete hormones into the blood, which signal only the specific target cells that recognize them anywhere in the body | 30 | |
| 5549586783 | neurosecretory cells | specialized nerve cells release hormones into the blood via extracellular fluid. | 31 | |
| 5549586784 | negative feedback | the effector response reduces the initial stimulus and eventually the response ceases. This feedback mechanism prevents overreaction by the system and wild fluctions in the variable being regulated | 32 | |
| 5549586785 | mechanisms of hormonal signaling | (a) a water-soluable hormone binds to a receptor protien on the surface of a target cell. this interaction triggers a signal transduction pathway that leads to a change in a cytoplasmic function or a change in gene transcription in the nucleus. (b) a lipid-soluable hormone penetrates the target cell's plasma membrane and binds to an intracellular receptor either in the cytoplasm or in the nucleus. The signal-receptor complex acts as a transcription factor, typically activating gene expression | 33 | |
| 5549586786 | One chemical signal, different effects | epinephrine the primary "fight or flight" hormone, produces different responses in different target cells. responses of the target cells may differ if they have different receptors for a hormone | 34 | |
| 5549586787 | cytokines | any group of proteins secreted by a number of cell types, including macrophages and helper T cells that regulate the function of lymphocytes and other cells of the immune system | 35 | |
| 5549586788 | hypothalamus | plays an important role in integrating the vertebrate endocrine and nervous systems this region on the underside of the brain receives information from nerves throughout the body, it initiates endocrine signals appropriate to environmental conditions | 36 | |
| 5549586789 | pituitary gland | a lima bean sized organ, endocrine gland located at the base of hypothalamus. consists of a posterior lobe (neurohypophysis) which stores and releases two hormones produced by the hypothalamus, and an anterior lobe (adenohypophysis) which produces and secretes many hormones that regulate diverse body functions | 37 | |
| 5549586790 | posterior pituitary | also called the neurohypophysis an extension of the hypothalamus composed of nervous tissue that secretes oxytocin and antidiuretic hormone made in the hypothalamus; a temporary storage site for these hormones. | 38 | |
| 5549586791 | neurohypophysis | posterior pituitary | 39 | |
| 5549586792 | anterior pituitary | also called the adenohypophysis; portion of the pituitary that develops from nonneural tissue; consists of endocrine cells that synthesize and secrete several tropic and nootropic hormones | 40 | |
| 5549586793 | adenohypophysis | anterior pituitary | 41 | |
| 5549586794 | tropic hormones | a hormone that has another endocrine gland as a target | 42 | |
| 5549586795 | antidiuretic hormone | A hormone produced in the hypothalamus and released from the posterior pituitary. It promotes water retetion by the kidneys as part of an elaborate feedback scheme that helps regulate the osmolarity of the blood | 43 | |
| 5549586796 | oxytocin | a hormone produced by the hypothalamus and released from the posterior pituitary. It induces contractions of the uterine muscles and causes the mammary glands to eject milk during nursing | 44 | |
| 5549586797 | nontopic hormones | produced by the anterior pituitary include prolactin, melanocyte-stimulating hormone | 45 | |
| 5549586798 | growth hormone | a hormone produced and secreted by the anterior pituitary that has both direct (nootropic) effects and tropic effects on a wide variety of tissues | 46 | |
| 5549586799 | neurons | nerve cells | 47 | |
| 5549586800 | nerves | bundles of fiberlike extensions of neurons. | 48 | |
| 5549586801 | cell body | the part of a neuron that houses the nucleus and other organelles | 49 | |
| 5549586802 | dendrites | one of usually numerous short highly branched processes of a neuron that convey nerve impulses toward the cell body | 50 | |
| 5549586803 | axon | a typically long extension or process from a neuron that carries nerve impulses away from the cell body toward target cells | 51 | |
| 5549586804 | axon hillock | the conical region of a neuron's axon where it joins the cell body; typically the region where nerve signals are generated | 52 | |
| 5549586805 | myelin sheath | In a neuron an insulation coat of a cell membrane from Schwann cells that is interuptted by nodes of Ranvier where saltatory conduction occurs | 53 | |
| 5549586806 | synaptic terminal | a bulb at the end of an axon in which neurotransmitter molecules are stored and released | 54 | |
| 5549586807 | synapse | The locus where one neuron communicates with another neuron in a neural pathway a narrow gap between a synaptic terminal of an axon and a signal-recieveing portion (dendrite or cell body) of another neuron or effector cell . Neurotransmitter molecules released by synaptic terminals diffuses across the synapse relaying messages to the dendrite or effector | 55 | |
| 5549586808 | neurotransmitters | a chemical messenger released from the synaptic terminal of a neuron at a chemical synapse that diffuses across the synaptic cleft and binds to and stimulates the postsynaptic cell | 56 | |
| 5549586809 | schwann cells | a type of glial cell that forms insulating myelin sheaths around the axons of neurons in the peripheral nervous system | 57 | |
| 5549586810 | membrane potential | the charge difference between a cell's cytoplasm and the extracellular fluid due to the differential distribution of ions. Membrane potential affects the activity of excitable cells and the transmembrane movement of all charged substances | 58 | |
| 5549586811 | resting potential | The membrane potential characteristic of a nonconducting excitable cell with the inside of the cell with the inside of the cell more negative than the outside | 59 | |
| 5549586812 | equilibrium potential (Eion) | the magnitude of a cell's membrane voltage at equilibrium calculated using the nernst equation | 60 | |
| 5549586813 | stretch-gated ion channels | protein pore in a cell's plasma membrane that opens when the membrane is mechanically deformed allowing the passage of certain ions | 61 | |
| 5549586814 | ligand-gated ion channels | protien pore in a cell's plasma membrane that opens or closes in response to a chemical signal allowing or blocking the flow of specific ions | 62 | |
| 5549586815 | voltage gated ion channels | a specialized ion channel that opens or closes in response to changes in membrane potential. | 63 | |
| 5549586816 | hyperpolarization | an electrical in which row inside of the cell is more negative relative to the outside than at the resting potential of -70 mV reducing the chance that the neuron will transmit a nerve impulse | 64 | |
| 5549586817 | depolarization | an electrical state in an excitable cell whereby the inside of the cell is made less negative relative to the outside than at resting potential. A neuron membrane potential. A neuron membrane is depolarized if a stimulus decreases its voltage from the resting potential of -70 mV in the direction of 0 voltage | 65 | |
| 5549586818 | graded potentials | a local voltage in a neuron membrane induced by stimulation of a neuron with strength proportional to the strength of the stimulus and lasting about a millisecond | 66 | |
| 5549586819 | threshold | the potential an excitable cell membrane must reach for an action potential to be initiated | 67 | |
| 5549586820 | action potential | a rapid change in the membrane potential of an excitable cell, caused by stimulus-trigged, selective opening and closing of voltage-sensitive gates in sodium and potassium ion channels. | 68 | |
| 5549586821 | saltatory conduction | rapid transmission of a nerve impulse along an axon resulting from the action potential jumping from one node of ranvier to another skipping the myelin sheathed regions of the membrane | 69 | |
| 5549586822 | synaptic vesicles | membranous sac containing neurotransmitter molecules at the tip of at the presynaptic axon | 70 | |
| 5549586823 | synaptic cleft | A narrow gap separating the synaptic knob of a transmitting neuron from a rececieving neuron or an effector cell | 71 | |
| 5549586824 | exitatory postsynaptic potentials (EPSPs) | an electrical change (depolarization) in the membrane of a postsynaptic neuron caused by the binding of an excitatory neurotransmitter from a presynaptic cell to a postsynaptic receptor makes it more likely for a postsynaptic neuron to generate an action potential | 72 | |
| 5549586825 | Inhibitory postsynaptic potentials (IPSPs) | an electrical charge (hyper polarization) in the membrane of a postsynaptic neuron caused by the binding of an inhibitory neurotransmitter from a presynaptic cell to a postsynaptic receptor makes it more difficult for a postsynaptic receptor to generate an action potential | 73 | |
| 5549586826 | Temporal summation | a phenomenon of neural integration in which the membrane potential of the postsynaptic cell in a chemical synapse is determined by the combined effect of EPSPs or IPSPs produced in rapid succesion | 74 | |
| 5549586827 | spatial summation | a phenomenon of neural integration in which the membrane potential of the postsynaptic cell is determined by the combined effects of EPSPs or IPSPs produced nearly simultaneously by different synapses | 75 | |
| 5549586828 | Acetylcholine | One of the most common neurotransmitters; functions by binding to receptors and altering the permeability of the postsynaptic membrane to specific ions, either depolarizing or hyper polarizing the membrane | 76 | |
| 5549586829 | serotonin | A biogenic amine synthesized from the amino acid tryptophan | 77 | |
| 5549586830 | epinephrine | a catecholamine hormone secreted from the adrenal medulla that mediates "fight or flight" responses to short term stress also functions as a neurotransmitter | 78 | |
| 5549586831 | dopamine | a biogenic amine closely related to epinephrine and norepinephrine | 79 | |
| 5549586832 | neuropeptides | a relatively short chain of amino acids that serves as a neurotransmitter | 80 | |
| 5549586833 | endorphins | any of several hormones produced in the brain and anterior pituitary that inhibits pain perception | 81 | |
| 5549586834 | biological clock | An internal timekeeper that controls an organism's biological clock marks time with or without environmental cues but often requires signals from the environment to remain tuned to an appropriate period | 82 | |
| 5549586835 | Lateralization | segregation of functions in the cortex of the left and right right hemispheres of the brain | 83 |
