Schwann cells – (PNS myelin) Myelinating Schwann cells wrap around axons of motor and sensory neurons to form the myelin sheath. the conduction of nervous impulses along axons, nerve development and regeneration, trophic support for neurons, production of the nerve extracellular matrix, modulation of neuromuscular synaptic activity, and presentation of antigens to T-lymphocytes. |. Oligodendrocytes - (CNS myelin) their main function is the insulation of axons in the CNS. * Satellite oligodendrocytes are functionally distinct from most oligodendrocytes.
When released by the sending neuron, neurotransmitters travel across the synapse and bind to receptor sites on the receiving neuron, thereby influencing where that neuron will generate a neural impulse. b) What is an agonist?
Also, we will discover its regiochemistry and stereochemistry. Hydration reaction is a process that gives a alcohol functional group and a hydrogen to a carbon-carbon double bond of an alkene. According to Markovnikov's rule the -OH group will be attached to the most substituted carbon which is a carbon connected to the most branches. As the result, in normal hydration reaction of (+)-α-Pinene, the -OH group will attach the carbon attaching to a methyl group. However, the desired product is (-)-Isopinocampheol, in which the -OH group need to attach to the less substituted carbon instead.
Substitutive Nomenclature: treats the halogen as a halo substituent on an alkane chain. The carbon chain is numbered in the direction that gives the substituted carbon the lower number. 4.3 IUPAC Nomenclature of Alcohols Place the Ol at the end 4.4 Classes of Alcohols and Alkyl
#7 In another synapse the neurotransmitter creates a graded potential which triggers an action potential in the lower motor neuron 6. #4 A primary interneuron forms an action potential and crosses to the opposite side of the brain. 7. #6 A stimulus from the Brain causes a graded potential and then an action potential to form in an upper motor neuron 8. #3 At a synapse a presynaptic sensory neuron stimulates the postsynaptic interneuron to form a graded potential in its cell
What do the neurotransmitter molecules do once they are released into the synaptic cleft? As the neurotransmitter chemicals travel across the synaptic cleft, they bind to receptors, such as the ones found on the ligand gated ion channels, on the postsynaptic membrane. 11. Neurotransmitters cause postsynaptic ion channels to open. Explain how this can lead to either a graded potential or a hyperpolarization.
Introduction Nucelophilic substitutions are chemical reactions in which an electron rich nucleophile attacks the electron poor electrophile1. There are two classes of nucelophilic reactions – SN1, and SN2. The SN1 reaction is a 2 step, uni-molecular reaction, which is independent of the nucleophile. It requires a highly substituted electrophile since there is a formation of a carbocation in its rate determining step, good polar protic solvents which stabilize the carbocation and a good leaving group1. On the other hand, a SN2 reaction is a concerted, bimolecular reaction which has one slow, transition state1.
Outline the body’s response to stress (6 marks) There are two types of stress: acute and chronic stress. Acute stress (short-term stress) causes the body to respond through a process called the sympthomedullary pathways. This immediate response is achieved because of the hypothalamus’s direct link to the nervous system which causes the activation of the sympathetic nervous system (SNS). This is a branch from the autonomic nervous system. The SNS also regulates the sympathetic adrenal medullary system (SAM).
This is thought to enhance wakefulness and attention. When a dopamine-producing, or presyneptic neuron is active, vesicles in the neuron release dopamine. Some of the dopamine molecules cross a tiny gap, or cleft, and attach to receptors on a dopamine-receiving, or postsynaptic neuron thereby activating it. Pumps on the transmitting cell then pull dopamine from the cleft and back into the cell. Methylphenidate the active ingredient in Ritalin attaches to this pump and blocks it making more dopamine available in the cleft for the signal-receiving neuron.
0.200 g KOH .1 mol of KOH56.11 g= 0.00356 mol of KOH Given the 1:1 stoichiometry of the reaction, 2-naphthol is the limiting reagent Theoretical yield = 0.5 g Percent yield=actual yieldtheoretical yield .100% 0.3189 g0.5g .100% 63.8 % | Conclusion A 63.8% yield of nerolin was recovered in the reaction of 2-naphthol and ethyl iodide. Given the stoichiometry of the reaction being 1:1, 2-naphthol was found to be the limiting reagent. Since the percent yield was not very high, it is plausible to assume that some errors may occurred that contributed for the lower yield. Those errors may be caused by the incomplete dryness of the product, loss of product during extraction and wrong amount of reagents. If the experiment was to be