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Figure 2 from Role of Amyloid Precursor Protein (APP) and Its Derivatives in the Biology and Cell Fate Specification of Neural Stem Cells. Figure 2 from Role of Amyloid Precursor Protein (APP) and Its Derivatives in the Biology and Cell Fate Specification of Neural Stem Cells. Figure 1 from Role of Amyloid Precursor Protein (APP) and Its Derivatives in the Biology and Cell Fate Specification of Neural Stem Cells. Synapse. In the nervous system, a synapse[1] is a structure that permits a neuron (or nerve cell) to pass an electrical or chemical signal to another neuron or to the target effector cell.

Synapse

Chemical or electrical[edit] There are two fundamentally different types of synapses: Neurotransmitter. Neurotransmitters are endogenous chemicals that enable neurotransmission.

Neurotransmitter

It is a type of chemical messenger which transmits signals across a chemical synapse, such as a neuromuscular junction, from one neuron (nerve cell) to another "target" neuron, muscle cell, or gland cell.[1] Neurotransmitters are released from synaptic vesicles in synapses into the synaptic cleft, where they are received by neurotransmitter receptors on the target cells. Many neurotransmitters are synthesized from simple and plentiful precursors such as amino acids, which are readily available from the diet and only require a small number of biosynthetic steps for conversion.

Neurotransmitters play a major role in shaping everyday life and functions. Their exact numbers are unknown, but more than 200 chemical messengers have been uniquely identified.[2][3][4] Dopamine - Wikipedia. We ask you, humbly, to help.

Dopamine - Wikipedia

Hi reader in Canada, it seems you use Wikipedia a lot; that's great! It's a little awkward to ask, but this Wednesday we need your help. We’re not salespeople. We’re librarians, archivists, and information junkies. We depend on donations averaging $15, but fewer than 1% of readers give. Dopamine - Wikipedia. Cysteine - Wikipedia. Cysteine (abbreviated as Cys or C)[3] is a semi-essential[4] proteinogenic amino acid with the formula HO2CCH(NH2)CH2SH.

Cysteine - Wikipedia

It is encoded by the codons UGU and UGC. The thiol side chain in cysteine often participates in enzymatic reactions, as a nucleophile. The thiol is susceptible to oxidization to give the disulfide derivative cystine, which serves an important structural role in many proteins. When used as a food additive, it has the E number E920. It can be seen as serine, but with one of the oxygen atoms replaced with sulfur; replacing said atom with selenium gives selenocysteine. Sources[edit] Dietary sources[edit] Although classified as a non-essential amino acid, in rare cases, cysteine may be essential for infants, the elderly, and individuals with certain metabolic disease or who suffer from malabsorption syndromes.

Cysteine is found in most high-protein foods, including: Like other amino acids, cysteine has an amphoteric character. Melanin - Wikipedia. Melanin pigment (light refracting granular material—center of image) in a pigmented melanoma.

Melanin - Wikipedia

Melanin (/ˈmɛlənɪn/ ( listen); from Greek: μέλας melas, "black, dark") is a broad term for a group of natural pigments found in most organisms. Melanin is produced by the oxidation of the amino acid tyrosine, followed by polymerization. The melanin pigments are produced in a specialized group of cells known as melanocytes.

There are three basic types of melanin: eumelanin, pheomelanin, and neuromelanin. In the human skin, melanogenesis is initiated by exposure to UV radiation, causing the skin to turn tan. Humans[edit] Because melanin is an aggregate of smaller component molecules, there are many different types of melanin with differing proportions and bonding patterns of these component molecules. Dopamine - Wikipedia. Melatonin - Wikipedia. Melatonin, also known as N-acetyl-5-methoxy tryptamine,[1] is a hormone that is produced by the pineal gland in animals and regulates sleep and wakefulness.[2] Melatonin is also produced in plants where it functions as a first line of defense against oxidative stress.[3] As a medicine, it is used for the treatment of insomnia; however, scientific evidence is insufficient to demonstrate a benefit in this area.[8] Melatonin is sold over the counter in the United States, Canada and some European countries.

Melatonin - Wikipedia

In other countries, it may require a prescription or it may be unavailable. History[edit] In 1958, dermatology professor Aaron B. Major Hormones: Origin, Target, Function - SchoolWorkHelper. Serotonin - Wikipedia. Monoamine neurotransmitter Serotonin ([6][7][8]) or 5-hydroxytryptamine (5-HT) is a monoamine neurotransmitter.

Serotonin - Wikipedia

It has a popular image as a contributor to feelings of well-being and happiness, though its actual biological function is complex and multifaceted, modulating cognition, reward, learning, memory, and numerous physiological processes such as vomiting and vasoconstriction.[9] Cerebrospinal fluid. The cerebrospinal fluid (CSF) is produced from arterial blood by the choroid plexuses of the lateral and fourth ventricles by a combined process of diffusion, pinocytosis and active transfer.

Cerebrospinal fluid

A small amount is also produced by ependymal cells. The choroid plexus consists of tufts of capillaries with thin fenestrated endothelial cells. These are covered by modified ependymal cells with bulbous microvilli. BC Online: 9E - Memory and Learning in Aplysis. This page has been compiled from several web pages and is not meant to be a cohesive chapter.

BC Online: 9E - Memory and Learning in Aplysis

For our last class we will listen to a tape of a talk, Remembrance of Things Past, by Nobel Laureate Eric Kandel. He won the 2000 prize in Medicine and Physiology for his study of memory and learning, especially in the sea snail, Aplysia. The information in the following page comes from web links (references) and are threaded together to present the background to the talk we will hear on Monday. Please read this thoroughly so you can be prepared to get the most out of his talk.

Next Yr: Handout from talk. Table of Contents — October 12, 2009, 364 (1531) Melanopsin retinal ganglion cell loss and circadian dysfunction in Alzheimer's disease (Review) 1.

Melanopsin retinal ganglion cell loss and circadian dysfunction in Alzheimer's disease (Review)

Introduction Alzheimer's disease, characterized by β-amyloid deposits and neurofibrillary tangles, is the most common type of dementia in the elderly population. The clinical duration is normally 8–10 years, and mortality often results due to secondary factors, such as pneumonia (1). When diagnosing the disease, pathologic findings of β-amyloid plaques and neurofibrillary tangles as well as the neuroimaging of gross cerebral cortical atrophy are the standard. Melanopsin. Medical lecture note and Powerpoint slides: Pituitary Gland. Median eminence - Wikipedia. The median eminence is part of the inferior boundary of the hypothalamus in the human brain. A small swelling on the tuber cinereum posterior to the infundibulum – atop the pituitary stalk – the median eminence lies in the area roughly bounded on its posterolateral region by the cerebral peduncles, and on its anterolateral region by the optic chiasm.

The median eminence is one of the seven areas of the brain devoid of a blood–brain barrier. It is sometimes considered one of the circumventricular organs.[1] Physiology[edit] The median eminence is a part of the hypothalamus from which regulatory hormones are released. Circumventricular organs - Wikipedia. Circumventricular organs (CVOs) are structures in the brain that are characterized by their extensive vasculature and lack of a normal blood brain barrier (BBB).[1] The CVOs allow for the linkage between the central nervous system and peripheral blood flow; additionally they are an integral part of neuroendocrine function.[2] The lack of a blood brain barrier allows the CVOs to act as an alternative route for peptides and hormones in the neural tissue to the peripheral blood stream, while still protecting it from toxic substances.[3][4] CVOs can be classified as either sensory or secretory organs.

The sensory organs include the area postrema (AP), the subfornical organ (SFO) and the vascular organ of lamina terminalis. They have the ability to sense plasma molecules and then pass that information into other regions of the brain. Research has also linked CVOs to body fluid regulation, cardiovascular functions, immune responses, thirst, feeding behavior and reproductive behavior.[2] Area postrema - Wikipedia. The area postrema is a medullary structure in the brain that controls vomiting. Its privileged location in the brain also allows the area postrema to play a vital role in the control of autonomic functions by the central nervous system.

Basal ganglia - Wikipedia. The main components of the basal ganglia – as defined functionally – are the striatum both dorsal striatum (caudate nucleus and putamen) and ventral striatum (nucleus accumbens and olfactory tubercle), globus pallidus, ventral pallidum, substantia nigra, and subthalamic nucleus.[3] Each of these components has a complex internal anatomical and neurochemical organization.

The largest component, the striatum (dorsal and ventral), receives input from many brain areas beyond the basal ganglia, but only sends output to other components of the basal ganglia. The pallidum receives input from the striatum, and sends inhibitory output to a number of motor-related areas. The substantia nigra is the source of the striatal input of the neurotransmitter dopamine, which plays an important role in basal ganglia function.

The subthalamic nucleus receives input mainly from the striatum and cerebral cortex, and projects to the globus pallidus. Structure[edit] Carbenoxolone - Wikipedia. Retinohypothalamic tract - Wikipedia. Structure[edit] The retinohypothalamic tract consists of retinal ganglion cells.[4] A distinct population of ganglion cells, known as intrinsically photosensitive retinal ganglion cells (ipRGCs), is critically responsible for providing non-image-forming visual signals to the brain. Intrinsically photosensitive retinal ganglion cells - Wikipedia. Intrinsically photosensitive retinal ganglion cells (ipRGCs), also called photosensitive retinal ganglion cells (pRGC), or melanopsin-containing retinal ganglion cells, are a type of neuron in the retina of the mammalian eye.

The presence of ipRGCs were first noted in 1923 when rodless, coneless mice still responded to a light stimulus through pupil constriction, suggesting that rods and cones are not the only light sensitive neurons in the retina. It wasn't until the 1980s that advancements in research on these cells began. Recent research has shown that these retinal ganglion cells, which, unlike other retinal ganglion cells, are intrinsically photosensitive due to the presence of melanopsin, a light sensitive protein. Therefore they constitute a third class of photoreceptors, in addition to rod and cone cells. [1] Suprachiasmatic nucleus - Wikipedia. 1806 The Hypothalamus-Pituitary Complex - Hypothalamus - Wikipedia.

Nervous system organization en - Afferent nerve fiber - Wikipedia. Afferent nerve fiber - Wikipedia. Golgi tendon organ - Wikipedia. The Golgi tendon organ (GTO) (also called Golgi organ, tendon organ, neurotendinous organ or neurotendinous spindle) is a proprioceptive sensory receptor organ that senses changes in muscle tension. Medulla oblongata - Wikipedia. Sense - Wikipedia. Five senses and the respective sensory organs inherent among Homo sapiens An allegory of five senses. Still Life by Pieter Claesz, 1623. Sense - Wikipedia. Physiological capacity of organisms that provides data for perception. Melanocyte - Wikipedia. Stria vascularis of cochlear duct - Wikipedia. Dark cell - Wikipedia. Vestibular system - Wikipedia. Cerebrum lobes - Proprioception - Wikipedia. Proprioception. Golgi tendon organ - Wikipedia.

Basal ganglia - Wikipedia. Area postrema - Wikipedia. Circumventricular organs - Wikipedia. Median eminence - Wikipedia. Hypothalamus - Wikipedia. Suprachiasmatic nucleus - Wikipedia.