Motor Neurone Disease Health And Social Care Essay

Motor Neurone Disease Health And Social Care Essay sensory neuron and motor neuron. Sensory neuron brings the signal from the target organ to brain in the form of electrical impulses and motor neuron has just the opposite function i.e. it brings the impulses from brain to target organ to respond against the particular stimulus. In MND these motor neurons are get affected that control voluntary muscle including speaking, walking, breathing, sawalloing and general movement of body. Skeletal muscle are innervated by a group of neurons (lower motor neuron) located in the ventral horn of spinal cord which projectout the ventral roots to the muscle cells. These nerve are innervated by corticospinal tract or upper motor neuron that project from motor cortex of brain. In microscopic pathology there is degeneration of ventral horn of spinal cord as well as atrophy of ventral roots. Introduction: Motor neuron disease (MND) are the group of neurological disorder. It affects the motor neurons. Motor neurons have main function in bringing the signal in form of impulses from brain to the effectors organs (target organ) and in this way control the voluntary activity like walking, speaking, swallowing and other general movements. A French neurologist, Jean Martin Charcot, first suggested club together all conditions that affect the lateral horn of spinal cord in 1869. The other common name for MND are- ALS (amyotrophic lateral sclerosis), primary lateral sclerosis (PLS), progressive muscular atrophy (PLS). The cause of MND is sporadic. Genetic factor and environmental factor are responsible for it up to some extent. The motor system mainly consist of four parts: pyramidal system, basal ganglia, cerebellum and neuromuscular system. The lesion in any of them can lead to neurodegenerative disease. There may be several reason associated with lesion like intracellular hemorrhage, stroke etc. There is not much scope available for treatment of this disease permanently. Medical science still does not have any effective and permanent cure. Here I am trying to use stem cell technology approach for the treatment of this disease. As stem cells are the master cells of human body and can have capacity to derive all kind of cells. Because of its versatile nature, these cell can generate the motor neuron cells which get degenerated in MND. Here some stem cells cell approach is being consider and technique involved for its treatment are neural stem cell approach, the delivery of stem cells into multiple site and affected area, induced pluripotent cells approach, glial restricted precursor approach, cell therapy approach etc. The motor system: The motor system consist of: Pyramidal system (upper motor neuron) The basal ganglia (extrapyramidal system) The cerebellum Neuromuscular system The normal motor pathway contain upper motor neuron that synapse in the brainstem and spinal cord with lower motor neuron. The nerve cell bodies of of upper motor neuron (UMNs) lie in the precentral gyrus of the cerebral cortex and in several brainstem nuclei, their axon synapse with motor nuclei in brainstem (cranial nerve nuclei) and the spinal cord (peripheral nerve). Lower motor neuron (LMNs) have their cell bodies in the anterior horn (AHC); their axon transmit impulse through their anterior root into peripheral nerve terminating at neuromascular [junction Rosa-Eva Huettl et al, Feb 2011]. Skeletal cells which are voluntary in nature are innervated by group of neurons (LMNs) which are located in the ventral horn of spinal cord and these nerve cells are innervated by corticospinal tract(UMN) which project from motor cortex of brain. Three kinds of motor pathways impringe on the anterior horn cells ; the corticospinal tract, the basal ganglia system, and the cerebellar system. These are additional pathway originating in brainstem that mediate flexor and extensor tone in limb movement and posture most notable in coma. All these higher motor pathways affect movement through the LMNs- so called the final common pathway. C:UsersGUDDU-SUDDUDesktoppari2.gif Fig 1: representation of motor cortex and internal capsule. The principal motor pathway (pyramidal tract) is depicated. The movement whether initiated voluntarily in the cortex, automatically in the basal ganglia or reflexly in the sensory receptors, must ultimately be translated into action via anterior horn cells. A lesion in any of the above mentioned area will affect movement or reflex activity. The three principal motor pathway are: The corticospinal (pyramidal) tract: the cortiocospinal (pyramidal) tracts mediate voluntary movement and integrate skilled, complicated, or delicate movement of selected muscular actions and inhibit others. They also carry impulses that inhibit tone, hence, their lesion results in hypertonia. The corticospinal fibres originate in the cerebral cortex (precentral mortex cortex) pass through corona radiata and condense in the internal capsule, pass through its posterior limb and travel own through mid brain, pons and comes down into lower medulla, where they form an anatomical structure resembling a pyramid. There most of the fibres cross to the opposite or contralateral side of the medualla, pass downwards and synapse with the anterior horn cells or with internuncial neurons. Tracts synapsing in the brainstem with motor nuclei of the cranial nerves are termed corticobullar fibres (tract). The basal ganglia system: it included motor pathways between the cerebral cortex, basal ganglia, brain stem and spinal cord. It controls tone, posture and body movement especially gross automatic movement such as walking. The cerebellum: it receives both sensory and motor inputs and controls the co-ordinates the motor activity, maintains equilibrium and control posture. Body part representation in motor cortex and internal capsule: The body part are represented in contraleteral hemisphere in a characteristic fashion i.e. lower limb occupies upper position, face occupied lower most, arm and trunk occupy a large area. Similarly, the parts of the body capable of performing delicate movements have largest cortical representation. In internal capsule, the representation of the part is reserved. The upper limbs, trunk and lower limbs occupy upper middle and lower parts of posterior limb of the internal capsule. Change in the posture and alteration in the tone of many muscles requires for the movement of body. Some quite distant from the part being moved. The motor system consist of hierarchy of control mechanism that maintain body posture, baseline, muscle tone upon which a specific movement is superimposed. The lowest order of the hierarchy lies in the gray matter of spinal cord which control the muscle tone in response to stretch and the reflex withdrawl to noxious stimuli. Above the spinal cord, circuits between basal ganglia and motor cortex constitute the extrapyramidal system which control background muscle tone and body posture and gate the initiation of movement. Cause of MND and symptoms associated with it: Almost 90% of MND cases are sporadic [Leyanx Xu et al, April 2009] i.e. the patient have not family record of this disease. Genetic factors and environmental factor is important in determing individuals sucettibility. Some genes linked to ALS are: Cu/Zn superoxide dismutase SOD1, ALS2, NEFH, SETX and vesicle associated with protein B (VAPB). SOD1 mutation is responsible for about 20% of the MND case among in a family. The main product of SOD1 gene is superoxide dismutase enzyme. It act as a free radical scavenger and function as to reduce the oxidative stress of cells throughout body [Gurney ME et al, April 1997] . Till now about more than 100 different kinds of mutation in SOD1 gene have been found, which account for development of MND and its some other forms as well (ALSOD database). AV4 is the most commonly mutation occurring in North America and occur in up to 50% of SOD1 cases. In such a way different region and countries have different mutation which directly or indirectly affect SOD1 gene. For instance, in Japan the most common mutation is H46R. D90A mutation is associated with the slow progression of ALS is found in the people of Scandinavian [Gurney ME et al, April 1997]. As SOD1 gene is involved in the reduction of oxidative stress so its mutation confers a gain in toxic and affect the nerve cells. Rather than this aspect lesion in various parts of the motor system produce distructive pattern of motor deficit. These can induce negative symptoms of weakness, lack of coordination, lack of stability and stiffness or positive symptoms such as tremor, dystonia, chorea, athetosis, hemiballism, tics and myoclonus. When the lower limbs are affected, characteristic pattern of gait disorder may result. Lower motor neuron lesion: It consist of anterior horn cells, nerve roots, peripheral nerves and myoneural junctions. Groups of muscle fibres innervated by single anterior horn cells (LMN) from a motor unit, hence, it will cause loss of function of these motor unit and muscle fibres innervated by them result into weakness, flaccid, paralysis, atrophy and wasting the muscles and these muscle fibres depolorise spontaneously producing fibrillation. Sign and symptoms of lower neuron lesion: Weakness or loss of movement. Decrease tone (hypotonia-flaccid paralysis). Loss of tendon and superficial reflexes. Wasting of muscle leading to atrophy. Fasciculation. Trophic change in skin and nail in neutropathies. Contractures of muscle. Upper motor neuron lesions: The corticospinal tract (UMM) extended from the cortex to spinal cord, when damaged or destroyed, its function are reduced or lost below the level of lesion. When UMNs are damaged above the crossover of tract in medulla, motor impairment develops on opposite or contralateral side. In damage below the crossover, motor impairment occur on same or ipsilateral side of body. A UMN lesion manifests clinically: Weakness of limb or limbs. Brisk tendon stretch reflexes and loss of superficial reflexs. Hypertonia i.e. spastic increase in tone greater in the extensors of lower limb and flexors of upper limb which is a characteristic pattern of hemiplegia. Extensor plantar responses. The weakness is more pronounced in extensors of upper limbs and flexors of lower limb. Little or no wasting of muscles. Extrapyramidal lesions: Disease of basal ganglia or extrapyramidal system does not cause paralysis but produce an increase in tone, disturbance in posture and gait, a slowness or lack of spontaneous and automatic movement termed bradykinesia, and a variety of involuntary movements. Cerebellar lesions: it leads to: Lack of coordination on the same side of body. The initial part of movement is normal but as target is approached and accuracy of movement deteriorates resulting in intention termor. Impairment of gait, equilibrium and postures. Lesions involving the cerebellar hemisphere lead to ataxic gait; while involvement of central vermis leads to truncal ataxia (patient has difficulty in sitting up, or standing). Decrease in muscle tone due to involvement of red nucleus. Paralysis is not a feature of cerebellar disease. Except all these stroke is also one of the commonest cause for motor neuron disorder. Diagnosis: Clinical diagnosis established by neurologist on the basis of neurological examination. Investigation such as blood test, EMG (electromyography), MRI (magnetic resonance image) and sometime genetic testing to diagnose the disease. The other way to diagnose the disease is by concentrating on symptoms and body condition. Treatment: Riluzole is the only drug that affect the course of disease [Theiss RD, et al, mar 2011]. This drug function by blocking the effect of neurotransmitter glutamine and is extend the life spain of an an ALS patient by only few months. Still there is no total cure of MND. The other treatment is being used are acute stroke management, as stroke is one of commonest cause of development of this disease. Stem cell approach for treatment of motor neuron disease: As mention above the main cause of this disease is degeneration of motor neurons. So application of stem cell technology in the generation of motor neuron can be very useful technique to treat this disease. Stem cells are the master cells of the human body. Because of versatile nature, stem cells have potential to repair or replace the degenerated cells. There are many issue which are important to be consider if we translate the current knowledge of stem cell into the treatment of neurodegenerative disease. First of all the clinically competitive and risk to the patient acceptable is necessary to be define. One of the important issue is that the proliferation and differentiation are difficult to control. Animal model may not fully predict their toxicity and risk involve for development of tumor formation after implantation [ Olle lindvall et al,4 jan 2010]. The disease pathology has to be determine that which cell be generating from stem cells. Different cells will be needed for different disease in replacement therapy. Prior to the clinical application, it must be demonstrated in animal model that stem cell based approach induce substantial improvement of function deficits that resemble the debilitating symptoms in patient. It is also important to determine biological mechanism involved the observed effect of stem cell treatment in animal model. Motor neuron cell has been developed invitro from different stem cells sources including mouse and human stem cells [Roy et al, year 2005]. Neural stem cells (NSCs) has been derived from fetal rat spinal cord [Lee H, et al. year 2007] and human forebrain and some other cells like iPS cells. These stem cell derived motor neuron precursors and neuroblast inviro. The motor neuron have extended axon to ventral roots. After transplanting into spinal cord of adult rabbit having the motor degeneration problem, form the neuromascular junction and it give rise to partial recovery from paralysis. after transplantation into the affected area of adult mice and maturation, the stem cells derived motor neuron and attend muscular atrophy. C:UsersGUDDU-SUDDUDesktoppari.jpeg Fig 2 : stem cell based therapeutic approach for motor neuron disease (ALS). ALS leads to degeneration of motor neuron in the cerebral cortex, brainstem, and spinal cord. The stem cell based approach can be induce neuroprotector or dampen detrimental inflammation by implanting stem releasing growth hormone. Finally stem cells derived spinal motor neuron precursor or neuroblast could be transplanted into damaged area to replace damaged or dead neurons. [ Olle lindvall et al,4 jan 2010] Still this approach has not been successful totally to cure MND in case of human. There a several experiment hurdle which must have to overcome so that the cell replacement therapy to become successful. To achieve this goal we must know the specificity of the cell target, homing and special markers. The stem cell must be delivered at multiple site along the spinal cord . the upper motor neuron formed must be innervates to the lower motor neurons the other important aspect is that differential of spinal motor neurons can be directed to the correct cervical, thoracis or lumber phenotype and finally cell project at axial or limb muscles . The central motor neuron like corticospinal neuron also can be replaced which gate degenerated in motor neuron disease. The life Spain of new motor neuron generated should be appropriate. It should also be determine weather the environment in the spinal cord of patient with ALS, which hostile to motor neuron, can be altered [ Olle lindvall et al,4 jan 2010]. The genetical factor is one of the important factor to be consider. The person having ALS carrying genetic mutation in the glial cell so modification of the microglial cell or astrocyte for long term survival of transplanted motor neuron. Stem cell transplantation to counteract motor neuron loss by releasing neurotrophic molecules or modifying the inflammatory environment, play a major role in disease progression. It is more near term clinical goal for ALS [ Olle lindvall et al,4 jan 2010]. Induced pluripotent stem (iPS) cells approach: Induced pluripotent stem (iPS) cell as indicated above in the previous section, can be one of the important approach to treat motor neuron disease. These iPS cells are derived from epigenetic reprogramming of somatic cells through the exogenous expression of transcription factor. These iPS cells are also having the characteristic property like to that of embryonic stem cells and hence can have the major impact on disease like neurodegenerative disorder and regenerative medicine. These iPS cells are also self renew and retain potential to be differentiated into all cell type of body [Evangelos kiskins et al]. The another approach to treat MND is directed differentiation of human induced pluripotent (iPS) cell to functional neural phenotype is unknown. Human embryonic stem cells, specified to neural lineage, this cell could be differentiated to form motor neuron with similar efficiency [S karumbayaram et al, July 2010]. Spinal muscular atrophy (SMA) is also one of the common type of neurological disorder leading to infant mortality. This cause selective loss of lower motor neurons which finally result into muscle weakness, paralysis and often death. In this iPS cells were used. iPS cells were taken from skin fibroblast from the child with SMA. These cells expanded robustly in culture, maintained the disease genotype and generate motor neuron that showed selective deficits compared to those derived from childs unaffected mother. This was very essential in many other aspects like it can be used to model the specific pathology seen in a genetically inherited disease, study disease mechanism, screen drug compounds and develop new therapies [Allison D Elbert et al, 15 jan 2009]. Recently human neural stem cells (NSC) graft ameliorate MND in SOD1 transgenic model [Leyan Xu et al, April 2009]. One of the important stem cell approach for treatment of MND is that stem cells derived motor neuron may not survive when exposed to the harsh microenvironment in spinal cord of ALS. Rather than this stem cell may be used for studying glia- mediated toxic mechanism and other therapies in ALS [Jason R Thonhoff et al, June 2008]. Cell therapy may be a promising new treatment for MND. Recently it has been shown a single low dose (106 cells) of mononuclear human umbical cord blood cells administrating intravenously to mice delayed symptoms progression and modestly prolong life span [Svitana Garbuzova Davis et al, 17 June 2010]. Conclusion: Motor neuron disease is due to degeneration of motor neurons. The reason associated with it may be several like genetic factor, environmental factor etc. lesion in the parts of motor system is also one of the important cause of motor neuron disease. Although still there is no permanent cure of this disease. Medical science is concentrating on controlling the factors which are responsible for account of this disease to cure this disease like stroke is one of the common cause for MND so medical science is concentrating to overcome this stroke. Except this, medical science is also concentrating on lesion cure this disease. The main problem with medical science is that it is unable to activate the degenerated cell. Once the cell is dead or degenerate is impossible to make active. The only possible way is replacement of those degenerative and dead cells. Studies are being done to replicate the function of the neuron in term of MEMS (microelectromechanicalsystem) which can be used to replicate the degenerated neurons with these MEMS based microdevices. Apart from all these aspect according to me, stem cell technology approach is the best way to cure this disease. Because the cell which gets degenerated are being replaced here by the new cells produced by stem cells. So the biological environment is being maintained and the normal physiology can be retained by development of same cells which gets degenerated. Still this approach is not being successful because of the experimental hurdle. There is need of more study specially in specificity of the cell target, homing and special markers so that the transplantation is appropriate and it produce the degenerated cells. The various clinical trials are in progress in USA and hopefully as in other animal models it will be also work on human.

College Admissions Essay: A Stepping Stone for Others :: College Admissions Essays

A Stepping Stone for Others    I have always had a passion to learn. My interest is in political theory and economics, hoping someday to become a lawyer and stateswoman. I realize that in order to reach any of these goals, a college degree is vital. When I in turn reach my goals, I will use them to encourage and uplift my community by investing my time, money, energy, and influence to become a stepping stone for others.    I feel the most important step in giving back to the community is to stay in the community. As a Mississippi native, I witness first hand some of the financial and economic set backs it faces. Although we are making tremendous progress, I know that I too must do my part in contributing to the well being of my community. So many times the best and brightest of our youth graduate from top Mississippi high schools, continue their college careers in another state, never to return again. After I have obtained my college degree from a Mississippi University, I will become an entrepreneur, contribute to my state by opening up a business, and provide jobs to help stimulate the economy.    With a college degree in the field of political science, and a career in law and politics, I would encourage youth to be active in the political arena. I would offer intern positions in my law firm to help provide youth with first hand experience to further understand our legal and justice system. I would also volunteer my time in becoming a speech and debate coach for a local high school, because it is very important to have corporate and professional involvement with schools. In a hopeful career as a state legislator, or perhaps a congresswoman, I would support legislation that would promote better conditions for our schools and teachers.    My community is very important to me.

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DBQ Federalist vs Antifederalist essays

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Biology Yeast Experiment Essay Example

Biology Yeast Experiment Essay Example Biology Yeast Experiment Essay Biology Yeast Experiment Essay Design Experiment to investigate the effect of the concentration of Sodium Hydrogen Carbonate on the rate of photosynthesis using Cobomba plant. Aim: The aim of the experiment is to investigate the effect of the concentration of Sodium Hydrogen Carbonate (NaHC03) on the rate of photosynthesis using a Cobomba plant. Hypothesis: As the concentration of NaHC03 increases the rate of photosynthesis of the Cobomba plant should increase, as there is a greater presence of a carbon dioxide, obtained from the carbonate, which is a key reactant in photosynthesis. However it is also expected that the rate of photosynthesis should plateau with reater amounts of NaHC03, because the Cobomba plant will not be able to use all the extra, available C02 as its enzymes physically do not have the ability to do so. Background Information: When dissolved in water, NaHC03 produces carbon dioxide gas: . As can be seen in the equation for photosynthesis, carbon dioxide is a reactant in photosynthesis: 6 C02 + 12 H20 + photons -+ C6H1206 + 6 02 + 6 H20. The presence of NaHC03 means that C02 is more readily available in larger quantities, to speed up the process of respiration. However if a large amount of C02 is present in the water the Cobomba plant will not be able to use it all, as the nzymes cannot function quick enough. Other limiting factors may also cause the rate to slow, such as light intensity. As can be seen in the equation for photosynthesis, 02 is a product of photosynthesis and thus the rate of photosynthesis can be calculated by the amount of 02 released when photosynthesis occurs. Variables: Independent Dependent Controlled How to measure/control Amount of NaHC03 added to water Using the same weighing scale and weighing boat each time to measure the amount of NaHC03. Also using fresh tap water each time, so that the concentration of NaHC03 would be exact Amount of oxygen released Measured using the water bath and 100cm3 measuring cylinder Temperature of water Stayed in the same room, and used a heat barrier to prevent any heat from the lamp from affecting the rate of photosynthesis. Light intensity Used a lamp, kept in the same position each time to keep the light intensity equal for each repeat. pH of water Used tap water each time, and used fresh tap water for every measurement to ensure no NaHC03 was left in the water. Apparatus Application/Justification 1 x 500cm3 beaker To contain water to allow the NaHC03 to dissolve in 1 x glass funnel To put Cobomba plant under so that oxygen released goes into the easuring cylinder 1 x 10cm3 measuring cylinder To collect oxygen that is released Cobomba plant The plant which will respire and provide the results 5gof NaHC03 It will dissolve in water to release C02 which will affect the rate of respiration 100cm3 measuring cylinder To act as a heat shield from the light Lamp To ensure that the Cobomba plant has a constant light source to enable photosynthesis. Weighing scale and boat To measure the amount of NaHC03 Glass stirring rod To stir the NaHC03 when it is put in water to evenly distribute the concentration Stopwatch To ensure that time lengths are accurate for each time the xperiment is carried out Scissors To cut the Cobomba stem Ruler To measure length of Cobomba plant Method: 1. Measure a length of IOcm of Cobomba plant using the ruler 2. Fill the 500cm3 beaker, up to 500cm3, with tap water and place the Cobomba in the water underneath the glass funnel 3. Place the 10cm3 measuring cylinder upside down on top of the funnel, and ensure that it fills up with water 4. Set up a heat barrier using the 100cm3 measuring cylinder and fill it with water. Place it in between a lamp and the 500cm3 beaker 5. Switch on the lamp and start the timer 6. Once four minutes has passed stop the timer, and note down what the volume of 02 is in the measuring cylinder 7. Start the timer again, and after six minutes stop it. Note down the volume of 02 in the measuring cylinder 8. From this it can be deduced how much 02 has been collected 9. Repeat steps 1-4, but next measure 0. g of NaHC03 using the weighing boat and the weighing scales 10. Add the NaHC03 to the beaker and stir it with the glass rod 11. Start the timer and stop it after four minutes to allow the Cobomba to adjust to the water with added NaHC03, and make sure to note down the volume of 02 after four minutes 12. Then start the timer again for a further so minutes. When this time is up write dow n the volume, and from that it can be deduced how much 02 has been released 13. Repeat steps 10-12, making sure to replace the water in the beaker each time with new water, but adding another 0. gof NaHC03 each time 14. Repeat steps 1-13 a minimum of four more times to allow an average to be obtained Risk Assessment: Risk Precaution Being burnt by the lamp Take care and move slowly Swallowing a large quantity of NaHC03 or getting it in your eyes Do not put NaHC03 near to face 02 Amount of NaHC03 (g) +1- 0. 001 g Volume of 02 collected (cm3) +1- 0. 1 cm3 2 3 4 5 Average (2 s. f) Standard Deviation (2 s. f) 0 0. 2 0. 1 0. 2 0. 1 0. 2 0. 16 0. 05 0. 5 1. 0 1. 5 2. 0 2. 5 0. 2 0. 3 0. 4 0. 6 0. 7 0. 1 0. 8 0. 28 0. 44 0. 72 0. 06 0. 07 0. 05 0. 4 Graph to show the amount of 02 released with different amounts of NaHC03 from photosynthesis attached Discussion: The results show a positive correlation that evidences that as the amount of NaHC03 increases, so does the volume of 02 collected. This shows that NaHC03 speeds up the rate of photosynthesis, as all each amount time the experiment was done the time limits were kept the same but with more NaHC03 the olume of 02 increased. Therefore this partly proves the hypothesis, because it is shown that the addition of more C02, provided by the NaHC03, increases the rate of photosynthesis. However the rate of photosynthesis did not begin to plateau, as the hypothesis had stated. This may have been because there was not a great enough range of measurements of NaHC03 used to allow this pattern to be shown. Evaluation: The time restraints were quite limiting, and had there been more time a greater amount of repeats could have been done which would have allowed a more accurate average to be calculated. A systematic human error was not being able to add the NaHC03 to the water at the same time as starting the stop clock, which means there may have been a difference of a few seconds between each time the experiment was done. The act of measuring was not as precise as it could have been, and to resolve this equipment with a greater degree of accuracy could have been used. Another error was the decision to use small amounts of NaHC03. The consequence of this was that the digits of the results obtained were very small. Not only did this make them hard to measure, but also it meant that there was not a hugely significant ifference with the amounts of NaHC03 added to the water. Furthermore the ratio of for a comparatively large volume of water. Therefore a greater amount of NaHC03 should be used if this experiment were to be repeated again. Another human error was the repeated use of the same Cobomba plant. This may have affected the results, because the plant will have been respiring for a long time and also may still have remains of NaHC03 on it that would not make the next measurement of NaHC03 precise. To solve this the same mass of Cobomba plant, but from a different stem, could have been used each time. However this also poses problems as different stems may respire at different rates in the first place. If time had allowed then the time that the plant was given to respire could have been extended. This would have given a greater volume of 02, and the results may be clearer. An increased range of NaHC03 masses could be used, and this would hopefully show the results as expected in the hypothesis. The light intensity in the room may have changed during the time the experiment was done in, as it was turning into evening, and this may have had an affect on the results. To improve this, the experiment ould have been carried out in a dark room, but with several lamps shining on the beaker with heat barriers in front of them. This would have allowed the light intensity to remain constant. Conclusion: To conclude, it can be seen from the results obtained in the experiment that the rate of photosynthesis of the Cobomba plant increases with an increased amount of NaHC03 in its surrounding water. Therefore this suggests that C02 has an affect on photosynthesis, and that with greater amounts of it available there is a greater rate of photosynthesis. Bibliography: 1B Study Guides, Biology, Oxford, Andrew Allott Appendix: Attached

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Microeconomic Questions - Assignment Example Unfortunately, since the heavy commercialization of Pepsi and Coca Cola in the 1980s, RC Cola has struggled to keep up with bringing its name forth to the general public. Presumably, RC Cola did not see the merit of wasting so much revenue on advertisements; its owners now of course, see the errors of their ways. RC cola must resort to advertising rather an lowering its prices because both Pepsi and Coca Cola have substantially-prominent name-recognition. Rather than using penetration pricing strategy (a strategy that involves undercutting the prices of competitors), RC Cola must get name recognition out there to compete on the same level as Pepsi and Coca Cola. Monopolistic Market Structures have a unique set of stratagems for optimal pricing and optimal profits. In a monopolistic market structure, the competition is between firms selling similar but not entirely-substitutable products. It is open to all firms that want to earn profits. The firms within a monopolistic market structure are profit maximizers and all of the firms have some market power. Saudi Arabia has strong government controls over major economic activities. It possesses one-fourth of the worlds proven petroleum reserves, ranks as the largest exporter of petroleum, and plays a leading role in OPEC. With its multiple oil reserves, the country still maintains low production costs and therefore will most likely remain the number one exporter of petroleum for a long time to come. The oil reserves also help in lowering the unemployment rate which generally hovers around 15%. The petroleum sector accounts for roughly 75% of revenues and 45% of GDP. About 40% of GDP comes from the private sector.1 By producing a consistently high amount of oil daily, the prices per barrel have continued to rise, as an increasing demand meets the expected quota. Other countries have ceased exporting their own oil because of the adequate amount produced by other leading contributors of the world’s

'The Secret Garden' by Frances Hodgson Burnett, it is frequently said, Essay

'The Secret Garden' by Frances Hodgson Burnett, it is frequently said, shows us the triumph of patriarchy. To what extent is this statement valid - Essay Example Mary is sent to live temporarily at the English clergyman, Crawford's house until she was to travel to her uncle in England. It seems Mary is passed from one patriarch to another in a patriarchal world. Basil Crawford acts like a young patriarch by singing and leading the other children to sing a rhyme to make fun of Mary and bully her. Mary goes to live at her uncle Archibald's Misselthwaite Manor, where the staff relate stories about Archibald's patriarchy. Mrs. Medlock, Archibald's housekeeper, tells Mary that she sacrificed attending her niece's wedding because she wanted to keep her job and 'do at once what Mr. Archibald Craven told her to do. She never dared ask a question.' (Burnett 1994). Mary is introduced to the patriarchal world of Archibald. Martha, the maid, reveals that the secret garden used to be the lovers' paradise that only Mr. and Mrs. Craven were allowed to access.. The secret garden is an enclosed space that symbolises the woman's space that is sharply defined away from the man's space. (Knauss 1987). Archibald appreciated the honor of sharing in it. He understood that it was his wife's sanctuary in her male dominated world of patriarchy. He allowed it when she was alive. After her death, Archibald felt helpless and needed to regain some control. The secret garden is opened with a symbolic key . This key denotes power and understanding. When Mrs. Craven died, Archibald does not understand his grief. He hides the key because he desires to exert his power through his patriarchy, which keeps his staff subdued and powerless. (Russell 2002). Martha's mother, Mrs. Sowerby, understands the need for a lonely female to do some gardening. She predicts correctly that Mary might like to do some gardening of her own. The garden is viewed as a type of female utopia where the female has her own private domain to rule. (Qian Ma 2004). Mary may not understand the psychology behind her action and none of this explanation is necessary in this work as it belongs to 'children's literature. Burnett uses an older or adult character (Martha) to explain the difficult concepts in the story in a simple way. Martha helps Mary to settle into Misselthwaite Manor by making her as comfortable as possible in Archibald's patriarchal household. Even the male gardener, Ben Weatherstaff, exercised his own ai r of patriarchy when he deliberately avoids her. Although Mary has a higher social status than himself, he is not a servant to 'be merely commanded by them (members of his employer's family) to do things'. (Burnett 1994). However, Ben is subject to his employer, Archibald's patriarchy, which rules over his own.Archibald finally consents to see Mary only after Mrs. Susan Sowerby talks to him about it. This is evidence that Archibald is a flexible patriarch who listens to advice. He is kind to Mary and readily gives her permission to do and have what she likes. Archibald does not seem to be a triumphant patriarch who gives orders to his charge. Mary observes that 'he is really a nice man, only his face is so miserable and his forehead is all drawn together.' Mary loves her secret garden. The secret garden with its isolation is a sign of rebellion against the surroundings of patriarchy. (Abalos 2002). She is under the control of her uncle, who exerts secondary control over her by his orders to his servants. Mary complained that she has nothing to do and nothing