By Z. Achmed. Eckerd College.
The digestive system consists of a in the periodontal membrane insert gastrointestinal (GI) tract and accessory into the cementum covering the Large Intestine (pp buy reglan 10mg mastercard. Peritoneal membranes line the abdominal (d) The interior of a tooth contains a wall and cover the visceral organs buy reglan 10 mg low cost. The layers (tunics) of the abdominal GI passageway connecting the oral and nasal tract are discount 10mg reglan mastercard, from the inside outward, the peristalsis, haustral churning, and mass cavities to the esophagus and larynx. The liver is divided into right, left, propria, and thin layers of smooth cavity, pharynx, and esophagus. Peristaltic waves of contraction push food contains liver lobules, the functional units mucosae. The stomach consists of a cardia, fundus, hepatic cells separated by modified muscularis consists of layers of body, and pylorus. The oral cavity is formed by the cheeks, the bile; it releases the bile through the Small Intestine (pp. The cystic duct and common bile duct into tongue and teeth are contained in the 1. The pancreas is both an exocrine and an (a) Lingual tonsils and papillae with common bile duct and pancreatic duct endocrine gland. Fingerlike extensions of mucosa, called the pancreatic islets, secretes the palatal folds, a cone-shaped intestinal villi, project into the lumen, hormones insulin and glucagon. Digestive System © The McGraw−Hill Anatomy, Sixth Edition Body Companies, 2001 674 Unit 6 Maintenance of the Body Review Activities Objective Questions 10. Describe how the gallbladder is filled with (c) covered with peritoneal membranes. What is the (d) located within the thoracic and (d) It is mixed with blood from the function of bile? Which of the following types of teeth are What are the biomechanical movements found in the permanent but not in the Essay Questions of the large intestine that make these deciduous dentition? Distinguish between the gastrointestinal What are some of the causes of cirrhosis? The double layer of peritoneum that supports the GI tract is called tract, viscera, accessory digestive organs, and gut. The deciduous (milk) teeth don’t matter (d) the tunica muscularis in the wall of the GI tract. Which surgery do you think would have (a) the pancreas (c) the tongue the tunic layers.
As table buy discount reglan 10mg on-line, depressed discount 10 mg reglan free shipping, anxious cheap reglan 10 mg mastercard, and resentful dependence on the substance becomes when the substance is not available. Indi- more pronounced, individuals may lose viduals with a psychological craving for a interest in self-care, may show a decreased substance may attribute their need to a desire for food, and may have a variety of personal ﬂaw in their character or may sleep disturbances, resulting in sleep dep- consider their need as a negative reﬂection rivation. Either interpretation fur- focused on obtaining more of the sub- ther contributes to lowered self-esteem stance. Psychosocial and Vocational Issues in Substance Abuse 225 Substance use can affect individuals’ Individuals with a substance use disor- ability to drive. Poor driving performance der may be unable to function within can result in accidents or arrests, which their social network. Social and family rela- problem, so that individuals must depend tionships are strained and often destroyed on others for their transportation needs. Decreas- experience not only decreased libido but ing reliability in performing social roles also adverse effects on sexual perform- and continued inability to maintain com- ance, including impotence, a common mitments cause those affected by the indi- side effect of chronic alcohol abuse. Indi- vidual’s deterioration to feel disappointed viduals recovering from a substance use and angry. Others in the social environ- disorder may need to learn or relearn the ment may have to alter their own roles to components of a healthy lifestyle, such as incorporate duties the individual once good hygiene and grooming, proper diet, had. These concerned and may eventually lead to re- aspects of daily living may be a vital part sentment or even banishment from the of an individual’s rehabilitation. Family members and associates may begin to withdraw from the individ- Social Issues ual emotionally. As individuals become increasingly more isolated, feelings of self- The social effects of substance-related loathing, guilt, and shame may develop. There is a may determine the social implications of strong relationship between substance use substance use. For example, the availabil- disorders and a variety of accidents; motor ity of substances within a group or as part vehicle accidents, for example, can lead to of a social event may determine whether physical disability not only for the indi- or not individuals participate in that vidual with the substance use disorder, but group or event. Thus, the loss of a driver’s The extent of the social tolerance of in- license and more serious criminal charges dividuals’ behavior while intoxicated may are potential effects of substance abuse either curtail or enhance substance use at and/or dependence. As individuals become increasingly sub- uals who become dependent on illegal stance-dependent, however, the substance substances may engage in illegal activities becomes more important and social con- to gain money for the purchase of addi- tacts and activities become less important. Even if they do not face crim- 226 CHAPTER 7 CONDITIONS RELATED TO SUBSTANCE USE inal charges, they can become focused on increases. Physical disability resulting obtaining the drug rather than on func- from substance abuse and/or dependence tioning in a productive social role. In other instances, the loss of these lems that may extend beyond issues of relationships is permanent. Some individual circumstances, therapeutic individuals may need to learn social recovery may involve the development of skills, work-appropriate behaviors, or good new social roles and relationships or the hygiene or grooming practices; some need reestablishment of old ones. Individuals who began abusing substances at an ear- Vocational Issues ly age may not have developed sufﬁcient work skills or work history to obtain In the early stages of a substance-related employment and may require additional disorder, individuals may be concerned education or job training.
When the membrane potential moves towards threshold potential (60±65 mV) an action potential is initiated (c) buy reglan 10mg amex. They can be excitatory (depolarising) or inhibitory (hyperpolarising) generally involving the opening or closing of K channels generic reglan 10 mg mastercard. This can be achieved directly by the G- protein or second messenger but more commonly by the latter causing membrane phosphorylation through initiating appropriate kinase activity buy 10 mg reglan with visa. Thus the activity of a neuron can be controlled in a number of ways by NTs activating appropriate receptors (Fig. Two basic receptor mechanisms are involved: (1) Ionotropic Those linked directly to ion channels such as those for Na (e. ACh nicotinic or some glutamate receptors) or Cl7 (GABA), involving fast events with increased membrane conductance and ion flux. With these the first messenger of synaptic transmission, the NT, activates a second messenger to effect the change in neuron excitability. They are normally associated with reduced membrance conductance and ion flux (unless secondary to NEUROTRANSMITTER SYSTEMS AND FUNCTION: OVERVIEW 15 Figure 1. In the former the neurotransmitter combines with a receptor that is directly linked to the opening of an ion channel (normally Na or C17) while in the latter the receptor activates a G-protein that can directly interact with the ion channel (most probably K or Ca2) but is more likely to stimulate (Gs) or inhibit (Gi) enzymes controlling the levels of a second messenger (e. These in turn may also directly gate the ion channel but generally control its opening through stimulating a specific protein kinase that causes phosphorylation of membrane proteins and a change in state of the ion channel. The latter (metabotropic) effects may either open or close an ion channel (often K) and are much slower (100s ms to min) than the ionotropic ones (1±10 ms). A variety of neuro- transmitters, receptors, second messengers and ion channels permits remarkably diverse and complex neuronal effects an increased Ca2 conductance) and may involve decreased Na influx (inhibitory) or K efflux (excitatory). These two basic mechanisms could provide a further classification for NTs, namely fast and slow acting, although one NT can work through both mechanisms using different receptors. The slow effects can also range from many milliseconds to seconds, minutes, hours or even to include longer trophic influences. What will become clear is that while one NT can modify a number of different membrane ion currents through different mechanisms and receptors, one current can also be affected by a number of different NTs. The control of neuronal excitability is discussed in more detail in Chapter 2. It has been known for many years that stimulation of muscle or cutaneous afferents to one segment of the spinal cord produces a prolonged inhibition of motoneuron activity without any accompanying change in conductance of the motoneuron membrane, i. Such inhibition is probably, therefore, of presynaptic origin and is, in fact, associated with a depolarisation of the afferent nerve terminals and a reduction in release of the excitatory NT. If it is assumed that the amount of NT released from a nerve terminal depends on the amplitude of the potential change induced in it, then if that terminal is already partly depolarised when the impulse arrives there will be a smaller change in potential and it will release less transmitter (Fig. There is no direct evidence for this concept from studies of NT release but electrophysiological experiments at the crustacean neuromuscular junction, which has separate excitatory and inhibitory inputs, show that stimulation of the inhibitory nerve, which released GABA, reduced the EPSP evoked postsynaptically by an excitatory input without directly hyperpolarising (inhibiting) the muscle fibre. Certainly when GABA is applied to various in vivo and in vitro preparations (spinal cord, cuneate nucleus, olfactory cortex) it will produce a depolarisation of afferent nerve terminals that spreads sufficiently to be recorded in their distal axons.