Term
| Intra-cellar fluid compartment(body fluid) |
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Definition
| 67% of total body h20 inside the cell. Accounts for 40% of body weight. |
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Term
| Extracellar fluid compartment(body fluid) |
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Definition
| 33% is out side the cell. 20% of ECF is blood plasma. 80% of the ECF is interstitial fluid contain in gel like matrix. Accounts for 20% of body weight. |
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Term
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Definition
is a meshwork of collagen and Elastin fibers linked to molecules of a gel-like ground substance and to plasma membrane Integins-Attachment cites. Integins- function in pairs of two integral proteins, which interact with both intracellar and extracellar molecules. Glycoprotein adhesion molecules that link intracellar and extracellar compartments.
Interstitial fluid resides in hydrated gel of ground substance. |
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Term
| Plasma Membrane-Transport |
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Definition
| Selectively permeable- allows certain kind of molecules to pass. Many important molecules have transporters and channels. |
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Term
| Carrier mediated transport |
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Definition
| involves specific protein transporters. |
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Term
| Non-carrier mediated transport |
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Definition
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Term
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Definition
| moves compounds down concentration gradient; required not energy |
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Term
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Definition
| move compounds against a concentration gradient; requires energy(ATP) and transporters. |
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Term
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Definition
| Non-polar compounds readily diffuse thru cell membrane. Also some small molecules such as CO 2 and H2O . Gas exchange occurs this way. Cell membranes are impermeable to charged and most polar compounds. Charged l t molecules must have an ion channel or transporter to move across membrane. Rate of diffusion of a compound depends on: Magnitude of its concentration gradient , Permeability of membrane to it, Temperature, and Surface area of membrane. |
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Term
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Definition
Is net diffusion of H 2O across a selectively permeable membrane. H 2O diffuses down its concentration gradient. H 2O is less concentrated where there are more solutes, Solutes have to be osmotically active, i.e., cannot freely move across membrane, H 2Odiffusesdown its concentration gradient until its concentration is equal on both sides of a membrane,
Some cells have water channels (aquaporins) to facilitate osmosis. |
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Term
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Definition
| Is the force that would have to be exerted to stop osmosis. Indicates how strongly H 2O wants to diffuse. Is proportional to solute concentration. |
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Term
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Definition
| 1 molar solution(1.0M) = 1 mole of solute dissolved in 1L of solution .Doesn't specify exact amount of H 2O |
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Term
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Definition
| 1 molal solution(1.0m) 1 mole of solute dissolved in 1 kg H2O |
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Term
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Definition
| Is the effect of a solution on osmotic movement of H2O |
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Term
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Definition
| solutions have same osmotic pressure |
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Term
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Definition
| solutions have higher osmotic pressure and are osmotically active. |
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Term
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Definition
| Solutions have lower osmotic pressure |
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Term
| Regulation of Blood Osmolality |
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Definition
| Blood osmolality is maintained in narrow rangearound300mOsmrange around 300mOsm. If dehydration occurs, Osmoreceptors in hypothalamus stimulate: ADH release , Which causes kidney to conserve H2O and thirst. |
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Term
| Carrier mediated transport |
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Definition
| Molecules too large and polar to diffuse are transported across membrane by protein carriers. Protein carriers exhibit: Specificity for single molecule. Competition among substrates for transport. Saturation when all carriers are occupied. This is called T m (transport maximum) |
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Term
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Definition
| Is passive transport down concentration gradient by carrier proteins. It does not require ATP. |
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Term
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Definition
| Is transport of molecules against a concentration gradient. ATP is required. |
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Term
| Na+/K+ pump- Primary Active transport |
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Definition
| Uses ATP to move 3 Na+ out and 2 K+ in. Against their gradients |
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Term
| Secondary Active Transport |
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Definition
| Requires ATP to first move Na+ uphill to create a gradient. Uses energy from “downhill” movement of Na+ to drive “uphill” transport of another molecule. Cotransport(symport) is secondary transport in same direction as Na+ . Countertransport (antiport) moves molecule in opposite direction to Na+ |
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Term
| Absorption - Transport Across Epithelial Membranes |
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Definition
| is transport of digestion products across intestinal epithelium into blood. |
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Term
| Re-absorption- Transport Across Epithelial Membranes |
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Definition
| transports compounds out of urinary filtrate back into blood. |
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Term
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Definition
| moves material from 1 side to other of epithelial cells. |
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Term
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Definition
| moves material through tiny spaces between epithelial cells |
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Term
| What are limit transport between cells? |
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Definition
| Transport between cells is limited by junctional complexes that connect adjacent epithelial cells. |
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Term
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Definition
| Moves large molecules and particles across plasma membrane. |
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Term
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Definition
Is difference in charge across membranes. Results in part from presence of large anions being trapped inside the cell. Diffusable cations such as K+ are attracted into cell by anions, Na+ is not permeable and is actively transported out.
Nernst Equation- Ex= 61 log [Xout]
z [Xin] |
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Term
| Resting Membrane Potential (RMP) |
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Definition
| Is membrane voltage of a cell not producing impulses. RMP of most cells is –65 to –85 mV. RMP depends on concentrations of ions inside and out RMP depends on concentrations of ions inside and out. And on permeability of each ion. Affected most by K+ because it is most permeable. Some Na+ diffuses in so RMP is less negative than EK+ |
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Term
| How does the Na+/K+ pump affect RMP? |
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Definition
| Role of Na+/K+ Pumps in RMP- Because 3 Na+ are pumped out for every2K+ taken in, pump is electrogenic. It adds about –3mV to RMP. |
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Term
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Definition
| Is how cells communicate with each other. Some use gap junctions thru which signals pass directly from 1 cell to the next. To respond to a chemical signal, a target cell must have a receptor protein for it. |
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Term
| Paracrine signaling cells |
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Definition
| secrete regulatory molecules that diffuse to nearby target cells |
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Term
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Definition
| 1 neuron sends neurotransmitter messages to another cell via synapses |
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Term
| Endocrine signaling cells |
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Definition
| secrete chemical regulators that move thru blood stream to distant target cells. |
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Term
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Definition
| May be ions (e.g. Ca++) or other molecules such as cyclic AMP (cAMP) or G-proteins. |
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Term
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Definition
| Are part of 2nd messenger pathway in many cells, Contain 3 subunits whose components dissociate when a cell surface receptor is activated, A subunit binds to an ion channel or enzyme, changing their activity. |
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Term
| Cell bodies-(soma) neurons |
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Definition
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Term
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Definition
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Term
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Definition
| is cell bodies in the CNS |
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Term
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Definition
| is cell bodies in the PNS |
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Term
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Definition
| Uninsulated gap between adjacent the Schwann cells . |
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Term
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Definition
| flow moves soluble compounds toward nerve endings. Via rhythmic contractions of axon . |
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Term
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Definition
| moves large and insoluble compounds bi directionally along microtubules; very fast. |
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Term
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Definition
| moves materials away from cell body. Uses the molecular motor kinesin. |
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Term
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Definition
| moves materials toward cell body. Uses the molecular motor dynein. Viruses and toxins can enter CNS this way. |
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Term
| Functional Classification of Neurons |
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Definition
Sensory/Afferent neurons conduct impulses into CNS.
Motor/Efferent neurons carry impulses out of CNS
Association/ Interneurons integrate NS activity. Located entirely Inside CNS. |
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Term
| Structural Classification of Neurons |
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Definition
Pseudounipolar- Cell body sits along side of a single process. e.g. sensory neurons.
Bipolar-Dendrite and axon arise from opposite ends of cell body. e.g. retinal neurons
Multipolar-Have many dendrites and one axon. e.g. motor neurons. |
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Term
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Definition
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Term
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Definition
| Schwann and satellite cells myelinate PNS axons. |
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Term
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Definition
| has oligodendrocytes, microglia, astrocytes and ependymal cells. Each oligodendrocyte myelinates several CNS axons, Ependymal cells appear to be neural stem cells ,Other glial cells are involved in NS maintenance |
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Term
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Definition
| In PNS each Schwann cell myelinates 1mm of 1 axon by wrapping round and round axon . Uninsulated gap between adjacent Schwann cells is called the node of Ranvier. |
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Term
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Definition
| Occurs much more readily in PNS than CNS. Oligodendrocytes produce proteins that inhibit regrowth. And form glial scar tissue that blocks regrowth. |
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Term
| Resting Membrane Potential (RMP) |
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Definition
| At rest, all cells have a negative internal charge and unequal distribution of ions: Results from: Large cations being trapped inside cell, Na+/K+ pump and limited permeability keep Na+ high outside cell high outside cell, K+ is very permeable and is high inside cell, Attracted by negative charges inside. |
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Term
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Definition
| Changes- Measured by placing 1 electrode inside cell and 1 outside. |
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Term
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Definition
| occurs when MP becomes more positive.Depolarization occur via diffusion. Do not require active transport, After an AP, Na+/K+pump extrudes Na+, recovers K+, |
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Term
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Definition
| MP becomes more negative than RMP |
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Term
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Definition
| MP returns to RMP .VG Na+channels close; VG K+ channels open , Electrochemical gradient drives K+ outward. Repolarizes axon back to RMP repolarization occur via diffusion. Do not require active transport, After an AP, Na+/K+pump extrudes Na+, recovers K+, |
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Term
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Definition
| channels are opened by depolarization. |
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Term
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Definition
| Is a wave of MP change that sweeps along the axon from soma to synapse. Wave is formed by rapid depolarization of the membrane by Na+ influx; followed by rapid repolarization by K+ efflux . APs Are All-or-None APs Are All or None. - When MP reaches threshold an AP is irreversibly fired.Because positive feedback opens more and more Na+ channels . Shortly after opening, Na+ channels close. and become inactivated until repolarization. |
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Term
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Definition
| Absolute refractory period: Membrane cannot produce another AP because Na+ channels are inactivated. |
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Term
| Relative refractory period |
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Definition
| occurs when VG K+ channels are open, making it harder to depolarize to threshold . |
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Term
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Definition
| Refer to how axon’s properties affect its ability to conduct current. Includes high resistance of cytoplasm. Resistance decreases as axon diameter increases. Current leaks out through ion channels. |
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Term
| Conduction in an Unmyelinated Axon |
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Definition
| After axon hillock reaches threshold and fires AP, its Na+ influx depolarizes adjacent regions to threshold. Generating a new AP. Process repeats all along axon. So AP amplitude is always the same. Conduction is slow. |
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Term
| Conduction in Myelinated Axon |
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Definition
| Ions can’t flow across myelinated membrane. Thus no AP’s occur under myelin. and no current leaks. This increases current spread. Gaps in myelin are called Nodes of Ranvier. AP’s occur only at the nodes. VG Na+ channels are present only at nodes. Current from AP at 1 node can depolarize next node to threshold . Fast because AP’s skip from node to node. Called saltatory conduction. |
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Term
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Definition
| Synaptic transmission at chemical synapses is via neurotransmitters (NT). Electrical synapses are rare in NS. |
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Term
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Definition
| Depolarization flows from presynaptic into postsynaptic cell through channels called gap junctions. Formed by connexin proteins. Found in smooth and cardiac muscles, brain, and glial cells. |
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Term
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Definition
| Synaptic cleft separates terminal bouton of presynaptic from postsynaptic cell. NT’s are in synaptic vesicles. Vesicles fuse with bouton membrane; release NT by Exocytosis. Amount of NT released depends upon frequency of AP’s. |
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Term
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Definition
| AP’s travel down axon to depolarize bouton. Open VG Ca2+channels in bouton. Ca2+is driven in by electrochemical gradient. Triggers exocytosis of vesicles; release of NT’s. |
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Term
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Definition
| is widely used NT. Used in the brain and ANS. Used in most neuromuscular juctions. |
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Term
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Definition
| These can be excitatory or inhibitory. Contain both NT receptor cite and an ion channel. Open when ligand (NT) binds. Formed by 5 polypeptide subunits. 2 units contain ACH binding cites. Opens when 2 ACHs bind. Permits diffusion of Na+ into and K+ out of postsynaptic cell. In ward of Na+ dominates. Produces EPSPs |
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Term
| G protein-couple channels |
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Definition
| NT receptor is not part of the ion channel .Is a 1subunit membrane polypeptide. Activates ion channel indirectly through G-proteins . |
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Term
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Definition
| Binding of 1 ACh activates G-protein cascade which affects gated K+ channels. Opens some, causing hyperpolarization . Closes others, causing depolarization. |
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Term
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Definition
| Inactivates ACh, terminating its action; located in cleft. |
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Term
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Definition
| neurons use acetylcholine as NT |
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Term
| neuromuscular junctions(NMJ)- |
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Definition
| The large synapses on skeletal muscle are termed |
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Term
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Definition
| Include serotonin, norepinephrine and dopamine. After release, are mostly inactivated by: Presynaptic reuptake and breakdown by monoamine oxidase (MAO) MAO inhibitors are antidepressants. Their receptors activate G-protein cascade to affect ion channels. |
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Term
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Definition
| Involved in regulation of mood, behavior, appetite and cerebral circulation. LSD is structurally similar . SSRIs(serotonin-specific reuptake inhibitors) are antidepressants e.g., Prozac, Zoloft, Paxil, Luvox . Block reuptake of serotonin, prolonging its action . |
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Term
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Definition
| There are 2 major dopamine systems in brain Nigrostriatal dopamine systemoriginates in the substantia nigra and is involved in motor control .Degeneration of this system causes Parkinson's disease. Mesolimbic dopamine systemis involved in behavior and emotional reward. Most addictions activate this system . Overactivity contributes to schizophrenia. Which is treated by anti-dopamine drugs |
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Term
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Definition
| Used in PNS and CNS. In PNS is a sympathetic NT . In CNS affects general level of arousal . Amphetamines stimulate NE pathways . |
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Term
| Polypeptide NTs (neuropeptides)- |
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Definition
| Cause wide range of effects .Not thought to open ion channels .Many are neuromodulators .Involved in learning and neural plasticity. Most neurons release a classical and polypeptide NT. CCKpromotes satiety following meals Substance P is a pain NT. Endorphins, enkephalinsand dynorphinare endogenous opioidNTs . Promote analgesia and mediate many placebo effects. Effects are blocked by naloxone, an opiate antagonist. Neuropeptide Yis most common neuropeptide. Inhibits glutamate in hippocampus. Powerful stimulator of appetite. Endocannabinoids similar to THC in marijuana. Are the only lipid NTs. Not stored in vesicles; are produced from lipids of the plasma membrane. Are retrograde NTs: they act on neuron that releases them. And thereby may be involved in learning. Like THC, they stimulate appetite |
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Term
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Definition
| Graded in magnitude. Have no threshold. Cause depolarization. Summate. Have no refractory period. |
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Term
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Definition
| Cable properties. cause EPSPs to fade quickly over time and distance Spatial summation takes place when EPSPs from different synapses occur in postsynaptic cell at the same time. |
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Term
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Definition
| occurs because EPSPs that occur closely in time can sum before they fade. |
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Term
| Central Nervous System (CNS)- |
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Definition
| Consists of brain and spinal cord Receives input from sensory neurons. Directs activity of motor neurons. Association neurons integrate sensory and motor activity. Perform learning and memory |
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Term
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Definition
| consists of neuron bodies and dendrites. |
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Term
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Definition
| (myelin) consists of axon tracts |
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Term
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Definition
| Is largest part of brain (80% of mass) Is responsible for higher mental functions. Its right and left hemispheres are interconnected by tract of the corpus callosum. |
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Term
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Definition
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Term
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Definition
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Term
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Definition
|
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Term
| Frontal and parital lobes of the Cerebral Cortex |
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Definition
| are separated by the central sulcus |
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Term
| Temporal lobe of the Cerebral Cortex |
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Definition
| contains auditory centers; receives sensory info from cochlea. Also links and processes auditory and visual info. |
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Term
| Occipital lobe of the Cerebral Cortex |
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Definition
| is responsible for vision and coordination of eye movements. |
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Term
| Insula of the Cerebral Cortex |
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Definition
| - plays role in memory encoding. Integrates sensory info with visceral responses. Coordinates cardiovascular response to stress. |
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Term
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Definition
| of frontal lobe is involved in motor control. |
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Term
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Definition
| of parietal lobe receives sensory info from areas controlled by precentral gyrus . |
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Term
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Definition
| Language areas of brain are known mostly from aphasias = speech and language disorders due to brain damage. |
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Term
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Definition
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Term
|
Definition
| is involved in language comprehension |
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Term
| Limbic System and Emotion |
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Definition
| The hypothalamus and limbic system are crucial for emotions. Including aggression, fear, feeding, sex and goal-directed behaviors. |
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Term
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Definition
| is critical for acquiring new memories. And consolidating short-into long-term memory. |
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Term
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Definition
| is a relay center thru which all sensory info (except olfactory) passes to cerebrum ) And plays role in level of arousal |
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Term
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Definition
| Is most important structure for homeostasis. Contains neural centers for hunger, thirst, body temperature. Regulates sleep, emotions, sexual arousal, anger, fear, pain and pleasure. Controls hormone release from anterior pituitary. Produces ADH and oxytocin |
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Term
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Definition
| Are body's daily rhythms Regulated by SCN(suprachiasmatic nucleus) of hypothalamus SCN is the master clock. Adjusted daily by light from eyes .Controls pineal gland secretion of melaton in which regulates circadian rhythms. |
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Term
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Definition
| Contains several nuclei of cranial nerves And 2 important respiratory control centers Apneustic and pneumotaxic centers . |
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Term
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Definition
| 2nd largest structure in brain Receives input from proprioceptors (joint, tendon and muscle receptors) Involved in coordinatng movements and motor learning |
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Term
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Definition
| Contains all tracts that pass between brain and spinal cord. And many nuclei of cranial nerves. And several crucial centers for breathing and cardiovascular systems. |
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Term
| Reticular Activating System (RAS) |
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Definition
| Is an ascending arousal system that originates in groups of neurons in the pons, midbrain reticular formation, hypothalamus and basal forebrain .These project to the cerebral cortex and control its level of arousal. Activation of the RAS promotes wakefulness; inhibition promotes sleep. |
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Term
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Definition
| Sensory info from body travels to brain in ascending spinal tracts Motor activity from brains travels to body in descending tracts. Ascending sensory tracts decussate (cross) so that brain hemispheres receive info from opposite side of the body Same for most descending motor tracts from brain. Descending Spinal Tracts Are divided into 2 major groups: Pyramidal (or corticospinal)tracts descend from cerebral cortex to spinal cord without synapsing Originate in motor cortex. Function in control of fine movements. Extrapyramidal (or Reticulospinal) tracts descend with many synapses Influence movement indirectly. |
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Term
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Definition
| (= collection of cell bodies outside CNS) |
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Term
|
Definition
| Consists of 12 pairs of nerves, 2 pairs arise from neurons in forebrain 10 pairs arise from midbrain and hindbrain neurons, Most are mixed nerves containing both sensory and motor fiber. |
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Term
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Definition
| Are mixed nerves that separate next to spinal cord into dorsal and ventral roots, Dorsal rootcomposed of sensory fibers, Ventral rootcomposed of motor fibers.There are 31 pairs: 8 cervical, 12 thoracic, 5 lumbar, 1 coccygeal |
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Term
| Autonomic nervous system(ANS) |
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Definition
| manages our physiology. By regulating organs and organ systems, and their smooth muscles and glands. |
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Term
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Definition
| ANS has 2 neurons in its efferent pathway 1st neuron (=preganglionic neuron) has cell body in brain or spinal cord Synapses with 2 neuron (=postganglionic neuron)in an autonomic ganglion. Postganglionic axon extends from autonomic ganglion to target tissue |
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Term
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Definition
| Most visceral organs receive dual innervation (supplied by both Symp and Parasymp) The 2 branches are usually antagonistic, e.g. in controlling heart rate , But can be complementary(cause similar effects), e.g. in controlling salivation , Or cooperative(produce different effects that work together to cause desired effect) such as with micturition. |
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Term
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Definition
| Hormones go to target cells that contain receptorproteinsforitreceptor proteins for it |
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Term
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Definition
| are derived from tyrosine or tryptophan.Include NE, Epi , thyroxine , melatonin. |
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Term
| Polypeptide/protein hormones |
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Definition
| are chains of amino acids Include ADH, GH, insulin, oxytocin, glucagon, ACTH, PTH. |
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Term
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Definition
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Term
|
Definition
| derived from cholesterol Include testosterone, estrogen, progesterone and cortisol. |
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Term
| Steroid and thyroid hormones |
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Definition
| are lipids Can diffuse into target cells |
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Term
| Common Aspects of Neural and Endocrine |
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Definition
| Both NS and endocrine system use chemicals to communicate. Difference between NTs and hormones is transport in blood and more diversity of effects in hormone targets . Some chemicals are used as hormones and NTs .Targets for both NTs and hormones must have specific receptor proteins. Must be way to rapidly inactivate both. |
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Term
| To function in physiological regulation:- |
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Definition
Targets must have specific receptor proteins
Regulatory molecule and receptor proteins causes a specific change of events.
Must be a way to rapidly inactivate both. |
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Term
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Definition
| A tissue usually responds to # of hormones |
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Term
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Definition
2 hormones work together to produce an effect .
Produce a larger effect together than individual effects added together . |
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Term
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Definition
| if it enhances responsiveness of a target organ to 2nd hormone. |
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Term
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Definition
| If action of 1 hormone inhibits effect of another |
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Term
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Definition
| is time required for blood level to be reduced by half . Ranges from mins to hrs for most (days for thyroid hormones) Normal tissue responses are produced only when hormones are in physiological range. |
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Term
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Definition
| doses can cause # of side effects. Probably by binding to receptors of other hormones . |
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Term
| Priming effect(upregulation) |
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Definition
| occurs when a hormone induces more of its own receptors in target cells. Results in greater response in target cell. |
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Term
| Desensitization(downregulation) |
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Definition
| occurs after long exposure to high levels of polypeptide hormone .Subsequent exposure to this hormone produces a lesser response .Due to decrease in # of receptors on targets .Most peptide hormones have pulsatile secretion which prevents down regulation |
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Term
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Definition
| Target cell receptors show specificity, high affinity, and low capacity for a hormone.Lipophilic hormones have receptors in target's cytoplasm and/or nucleus because can diffuse thru plasma membrane . |
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Term
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Definition
| Their target is the nucleus where they affect transcription and takes at least 30 mins Receptors for water solubles are on surface of target cell |
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Term
|
Definition
| These act through 2nd messengers; effects are quick Some steroids also act on cell surface receptors |
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Term
| Nuclear Hormone Receptors |
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Definition
| Lipid hormones travel in blood attached to carrier proteins .They dissociate from carriers to pass thru plasma membrane of target Receptors. Serve as transcription factorswhen bound to hormone ligands . Activate transcription. Constitute a "superfamily" composed of steroid family and thyroid hormone family (which includes vitamin D and retinoic acid).Have ligand (hormone)-binding and DNA-binding domains. Binds hormone and trans locates to nucleus. Binds to hormone-response element (HRE) on DNA located adjacent to target gene. |
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Term
| Mechanisms of Steroid Hormones |
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Definition
| HRE consists of 2 half- sites 2 ligand-bound receptors have to bind to each HRE (dimerization) This stimulates transcription of target gene. |
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Term
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Definition
| Water soluble hormones use cell surface receptors because cannot pass through plasma membrane. Actions are mediated by 2nd messengers . Hormone is extracellular signal; 2nd messenger carries signal from receptor to inside of cell. |
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Term
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Definition
| Mediates effects of many polypeptide and glycoprotein. Hormone binds to receptor causing dissociation of a G-protein subunit. G-protein subunit binds to and activates adenylate cyclase, Which converts ATP into cAMP . cAMP attaches to inhibitory subunit of protein kinase. Inhibitory subunit dissociates, activating protein kinase . Which phosphorylates enzymes that produce hormones effects cAMP inactivated by phosphodiesterase. |
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Term
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Definition
| +- Serves as 2nd messenger system for some hormones. Hormone binds to surface receptor, activates G protein, which activates phospholipase C. Phospholipase C splits a membrane phospholipid into 2nd messengers IP3and DAG IP 3diffuses through cytoplasm to ER. Causing Ca2+channels to open. Ca2+diffuses into cytoplasm and binds to and activates calmodulin.Ca2+-Calmodulin activates protein kinases which phosphorylate enzymes that produce hormone's effects. |
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Term
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Definition
| Is used by insulin and many growth factors to cause cellular effects. Surface receptor is tyrosine kinase. Consists of 2 units that form active dimer when insulin binds. Activated tyrosine kinase phosphorylates signaling molecules that induce hormone/growth factor effects. |
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Term
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Definition
| Insulin stimulates glucose uptake by means of GLUT 4 carrier proteins 2nd messengers cause vesicles containing GLUT4 transporters to be inserted into plasma membrane. |
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Term
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Definition
| Pituitary gland is located beneath hypothalamus at base of the forebrain. Posterior pituitary stores and releases the hormonesAntidiurectic hormone-ADH- asopressin which increases H2O readsorption in the kidneys(And an decrease of Urine output). Inserts aquaporins. and oxytocin-is responsible for child birth and organism that are made in the hypothalamus. |
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Term
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Definition
| makes , stores and releases7hormones. Releasing of hormones controlled by releasing and inhibiting hormones from the Hypotalamus. 1. Growth hormone(GH) promotes growth, protein synthesis, and movement of amino acids into cells. 2. Thyroid stimulating hormone(TSH) stimulates thyroid to produce and secrete T4and T3 3. Adrenocorticotrophichormone(ACTH) stimulates adrenal cortex to secrete cortisol, aldosterone. 4.Follicle stimulating hormone(FSH) stimulates growth of ovarian follicles and sperm production 5.Luteinizinghormone(LH)causes ovulation and secretion of testosterone in testes 6.Prolactin(PRL) stimulates milk production by mammary glands. 7. Melanocite Stimulating Hormone- Increase skin pigmentation (in frogs). |
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Term
|
Definition
| Sit on top of kidneys. Each consists of outer cortex and inner medulla which arise differently during development, Medulla synthesizes and secretes 80% Epi and 20% NE , Controlled by sympathetic. Cortex is controlled by ACTH and secretes: Cortisol which inhibits glucose utilization and stimulates gluconeogenesis Aldosteronewhich stimulate kidneys to reabsorb Na+andsecreteK+. And some supplementary sex steroids |
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Term
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Definition
| Is located just below the larynx. Secretes T 4and T3 which set BMR and are needed for growth, development Consists of microscopic thyroid follicles Outer layer is follicle cellsthat synthesize T 4 . Interior filled with colloid, a proteinrich fluid. |
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Term
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Definition
| Are 4 glands embedded in lateral lobes of thyroid gland. Secrete Parathyroid hormone(PTH) Most important hormone for control of blood Ca2+levels. |
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| Is located in basal forebrain near thalamus. Secretes melatonin in response to activity of suprachiasmatic nucleus(SCN)of hypothalamus |
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| Solutes that cannot freely pass thought a membrane are said to be: |
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| In the phospholipase C more chanism , most of the increase intra-cellarular calcium comes from _________. |
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| Inositoltriphospate (IP3) |
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Definition
| Which of the following directly intiates the release of calcium ions from the endoplasmic reticulum. |
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| Both reploarization and relative refractory period are correct. |
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| The period of time when Na+ channels are recovering from their inactive state and K+ channels are still open is: |
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| The Na+/K+ pump transport ______ in to the cell and ______ out the cell per cycle. |
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| The paravertebral and collectral ganglia are associated with __________ division of the autonomic nervous system. |
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| The mylin sheaths of CNS nervous system are produced by___________. |
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