Monday, May 25, 2020

How to Draw a Lewis Structure

A Lewis structure is a graphic representation of the electron distribution around atoms. The reason for learning to draw Lewis structures is to predict the number and type of bonds that may be formed around an atom. A Lewis structure also helps to make a prediction about the geometry of a molecule. Chemistry students are often confused by the models, but drawing Lewis structures can be a straightforward process if the proper steps are followed. Be aware there are several different strategies for constructing Lewis structures. These instructions outline the Kelter strategy to draw Lewis structures for molecules. Step 1: Find the Total Number of Valence Electrons In this step, add up the total number of valence electrons from all the atoms in the molecule. Step 2: Find the Number of Electrons  Needed to Make the Atoms Happy An atom is considered happy if the atoms outer electron shell is filled. Elements up to period four on the periodic table need eight electrons to fill their outer electron shell. This property is often known as the octet rule. Step 3: Determine the number of bonds in the molecule Covalent bonds are formed when one electron from each atom forms an electron pair. Step 2 tells how many electrons are needed and Step 1 is how many electrons you have. Subtracting the number in Step 1 from the number in Step 2 gives you the number of electrons needed to complete the octets. Each bond formed requires two electrons, so the number of bonds is half the number of electrons needed, or: (Step 2 - Step 1)/2 Step 4: Choose a Central Atom The central atom of a molecule is usually the least electronegative atom or the atom with the highest valence. To find electronegativity, either rely on periodic table trends or else consult a table that lists electronegativity values. Electronegativity decreases moving down a group on the periodic table and tends to increase moving from left to right across a period. Hydrogen and halogen atoms tend to appear on the outside of the molecule and are rarely the central atom. Step 5: Draw a Skeletal Structure Connect the atoms to the central atom with a straight line representing a bond between the two atoms. The central atom can have up to four other atoms connected to it. Step 6: Place Electrons Around Outside Atoms Complete the octets around each of the outer atoms. If there are not enough electrons to complete the octets, the skeletal structure from step 5 is incorrect. Try a different arrangement. Initially, this may require some trial an error. As you gain experience, it will become easier to predict skeletal structures. Step 7: Place Remaining Electrons Around the Central Atom Complete the octet for the central atom with the remaining electrons. If there are any bonds left over from Step 3, create double bonds with lone pairs on outside atoms. A double bond is represented by two solid lines drawn between a pair of atoms. If there are more than eight electrons on the central atom and the atom is not one of the exceptions to the octet rule, the number of valence atoms in Step 1 may have been counted incorrectly. This will complete the Lewis dot structure for the molecule. Lewis Structures vs Real Molecules While Lewis structures are useful, especially when youre learning about valence, oxidation states, and bonding, there are many exceptions to the rules in the real world. Atoms seek to fill or half-fill their valence electron shell. However, atoms can and do form molecules that are not ideally stable. In some cases, the central atom can form more than other atoms connected to it. Also, the number of valence electrons can exceed 8, especially for higher atomic numbers. Lewis structures are helpful for light elements but less useful for transition metals, including lanthanides and actinides. Students are cautioned to remember Lewis structures are a valuable tool for learning about and predicting the behavior of atoms in molecules, but they are imperfect representations of real electron activity.

Thursday, May 14, 2020

Short Story Chapter 1 - 1321 Words

â€Å"Yes, Captain I am fine with that.† â€Å"Okay, you are dismissed, if you have any questions or concerns, please don’t hesitate, come straight to me.† â€Å"Don’t worry Captain if I have any questions I am sure Warren here will help me out.† He said with a dazzling smile and the first words I heard him speak. His country drawl hung deep in his words when he spoke. He clearly didn’t live around here his whole life. With that I got to my feet and left the Captain’s office and headed for my desk. He followed me like a lost puppy and pulled up a chair from another desk and sat with the back of the chair to his chest. â€Å"So, partner what do we got in store today?† He said with a sly smile on his face. â€Å"We don’t have anything to do, but I have something†¦show more content†¦I wanted to smack that smile off his face. I stared at him for a few minutes and realized that people were starting to stare and I felt my cheeks heat. I walked over to the elevator and hesitated, I really didn’t want to be trapped on there with him. So, I veered to the right and made my way down the stairs to the case file room. He followed me even though he stopped and looked at the elevator. He shrugged and kept going behind me. When we got down to the file room there was an officer sitting at the desk behind the locked gate. â€Å"Hey Warren† he stood up and dusted the chip crumbs from his uniform. His name was Stanley Upton and he was a good cop, but he stammered a lot when he spoke to me. He was about ten years older than me and put down here since he was shot on the job during a bank robbery five years back. I ignored the chip crumbs that he had still in his beard and smiled at him. â€Å"Hey Upton, I am here to sign out a cold case and I am showing the new Detective around the station. This is Detective Ford, Ford this officer Upton.† Upton’s smiled faded for just a second. Clearly not excited to see the new handsome Detective strutting around the station. That makes two of us. Upton handed me the sign in sheet and a bin to place our guns in, then he hit the buzzer to unlock the gate. â€Å"Do you need me to look up the case number and show you where it is?† â€Å"No, Upton I have looked into this case a few times I know exactly where itShow MoreRelatedShort Story : A Short Chapter : Chapter 1971 Words   |  4 PagesIse said nothing though she did raise an eyebrow. Naoko coughed nervously and continued, â€Å"It’s just an idea but I’d like to at least try it out to see if it’ll even work and since you’re said to be really god with kidÃ…  I thought you could help me.† Ise’s face still looked unamused though when she spoke there was a hint of interest in her voice, â€Å"How did you come up with that idea?† The teen shrugged, â€Å"I read about a weapon Quincies have used called Seele Schneider. It’s like a sword but made ofRead MoreShort Story : A Short Chapter : Chapter 1739 Words   |  3 Pagesâ€Å"I guess Yuri was right, which is mildly convenient† Sabra said. â€Å"The place is almost empty, their numbers are extremely low.† Screaming from a young woman could be heard coming from another room, surprising them. Turning their attention in the direction the scream was coming from. Everyone tried to move towards the screaming, before being halted by Paisley. â€Å"One group can go check that out. We need to go and look for Vittorio, it shouldn’t be an issue to split up for a little.† â€Å"I’m certainRead MoreShort Story : A Short Chapter : Chapter 11430 Words   |  6 Pagesher eyes, which were unable to see his in the darkness, then he checked to see Torins hand placed against her small waist more in reassurance than in having to hold her close to the wall. Once they reached the top landing, Duncan pulled the short braided rope attached to an old bronze ships bell. The clang rang off the stone walls which echoed loud enough to surly raise the dead at the very least to alert the household as was the intent. Duncan stepped back to let the door swing outward, whichRead MoreShort Story : A Short Chapter : Chapter 12137 Words   |  9 Pagesbrothers got in and went back to the motel. â€Å"Fay gets the bed,† Sam was about to protest when Dean quickly shut him up. â€Å"She stabbed a ghost in the eye twice, killed him, made friends with a ghost, and saved both our asses,† Fay just grabbed her black shorts and tank then walked into the bathroom. Stripping down, she turned on the hot water, letting the warmed rinse off the dirt and grime from the asylum. Turning off the water, she grabbed her toothbrush. As she got out the toothpaste there was a knockRead MoreShort Story : A Short Chapter : Chapter 12195 Words   |  9 Pageshappened to me would be considered within parameters. From there, they let me out of the machine and I faked being Sister long enough to be sent on my way.† Finishing off my water I set it down and nervously licked my lips. â€Å"And that’s basically my story. After leaving I got a new kit, put myself up in a hotel and over the next few days I wandered around, saw the city, did some research, and experimented a bit with being an Esper... Any questions?† Mikoto and Kuroko stared at each other and at Mikoto’sRead MoreShort Story Chapter 11266 Words   |  6 Pagesfright. Drakes smirk grew as he noticed this. You dont have a choice. As soon as those words made their way into the dead air he bolted towards the other boy. Shadow pushed Jace behind him and braced for the incoming attack, and not like other stories, this one hit its mark. He winced, and noted the body behind him. Activating the pipes in his calves he dashed towards a clearing only to take a fireball to the back. Come back and fight me coward! Drake was catching up fast. Shadow struggledRead MoreShort Story Chapter 1774 Words   |  4 PagesThey made it out of Viridian Forest not long after defeating that swarm of Beedrill. It was getting close to evening by the time they made it to the next route, so they stopped to make camp for the night. It would be another two hours before they could make it to Pewter City if they continued. It was safest to just make camp. They sat around the fire Spitfire had made for them. Misty was the only one who didnt release her Pokà ©mon. Rattata snuggled in Gabbys lap and ate from the bag of chips inRead MoreChapter 1 Short Story922 Words   |  4 Pagesfather’s council table. He looks to her for advice even in granting justice. Since her mother’s death, the Princess is more the Queen than anything els e. She might offer you some perspective.† Gwen nodded. She glanced toward the sky to see Sol just short of his zenith overhead. â€Å"Perhaps we should ride on then?† â€Å"We’d make Whitgate in a few hours. Perhaps we might find suitable lodgings afterwards?† Seeing Gwen’s reluctance to put her out further in her eyes, Blancheflor insisted, â€Å"You are my guestRead MoreChapter 1 : A Short Story1136 Words   |  5 PagesKaterina stepped out of the shadow of the filing cabinet. She pushed her hood down and swung her sniper off of her back before leaning it against the wall. â€Å"Hey Maria.† She said as she placed the suitcase onto agent Hills desk. The brunette glanced at her before she looked back to her computer screen and continued to type. â€Å"Hello, Shadow.† The young woman snorted and quickly appeared next Hill, slinging an arm over her shoulders. â€Å"Oh, don’t be like that. You know calling me ‘Agent Volkova’ overRead MoreShort Story : Chapter 11085 Words   |  5 PagesThe pillow seemed to sink a little, and Johnny died. I looked towards Dally, his face turned ten times younger, his face, his hard, mean, face had tears rolling down it. â€Å"...Johnny†¦Ã¢â‚¬  his voice whispered faintly, but Johnny said nothing. He could not. Dally had a pained expression that only someone who knew him could recognize, his hands were in fists. â€Å"We’re leaving,† Dally demanded, â€Å"Wait† the nurse said jogging towards us, â€Å"Johnny wanted you to have this.† she handed me Gone With the Wind. I took

Wednesday, May 6, 2020

Symptoms And Symptoms Of Alzheimer s Disease - 1642 Words

Abstract Alzheimer’s disease is a brain disorder when brain cells degenerate and die. Alzheimer’s dieses destroys the patient’s memory within time. The mental functions of the brain also get destroyed when a person gets Alzheimer’s. Alzheimer’s disease is most commonly seen when the patient is sixty to seventy years old. In this research paper the reader will learn about the signs and symptoms, causes, course of disease, outcome and secondary diagnosis, treatment, and prognosis and survival. Signs and Symptoms There are several different ways to tell if a person has or is getting Alzheimer’s disease. There are ten early signs and symptoms of Alzheimer’s disease. The first symptom is memory loss. Memory loss is the most common symptom. People with Alzheimer’s disease tend to forget new things, names, and dates of important events such as anniversaries or birthdates. Another thing that Alzheimer’s effects with memory is the short term part. This will make people with Alzheimer’s disease ask questions over and over again in anchors amount of time in between. The second symptom is having trouble to plan or solve problems, or completing familiar tasks at home. This is where it is hard for the people who have Alzheimer’s disease it is hard for them to do simple tasks such as cooking or following a recipe. Also, working with numbers such as paying the bills or balancing a checkbook. People with Alzheimer’s disease may a lso have trouble with doing the simpleShow MoreRelatedSymptoms And Symptoms Of Alzheimer s Disease930 Words   |  4 PagesAlzheimer’s Disease Kevin Arnold from the Wonder Years said â€Å"Memory is a way of holding on to the things you love, the things you are, and the things never want to lose.† Memories are the things that are upheld, whether good or bad, those memories are imprinted in the mind and cannot be taken away that is, until later in life. As one ages it is natural for some memories to fade. Loss of memories and brain function deficits that occur and are not from normal aging may indicate a person is sufferingRead MoreSymptoms And Symptoms Of Alzheimer s Disease3214 Words   |  13 Pages NEU ID: 001983161 Donepezil and other acetylcholinesterase inhibitors in Alzheimer’s disease Abstract: Alzheimer’s disease (AD), discovered by Dr. Alois Alzheimer in 1907, is the most common form of dementia. The early symptom of Alzheimer’s disease is having difficulty in remembering recent events. At the advanced stage, the signs and symptoms of AD include: memory loss, confusion, trouble concentrating, frustration, irritability difficulty in saying, difficultyRead MoreSymptoms And Symptoms Of Alzheimer s Disease2317 Words   |  10 Pagesthey age and the various experiences they go through. One of the most common diseases among older people is dementia. Among the different types of dementia, the most prevalent one is Alzheimer’s disease (AD). It is important to look at all of the signs and symptoms of each type of dementia to see which specific type best describes a person’s condition. There is one patient in particular, Betty, who has many signs and symptoms related to dementia. Betty is a 65-year old woman who has dementia runningRead MoreSy mptoms And Symptoms Of Alzheimer s Disease2374 Words   |  10 PagesAs a society, we are constantly faced with negative news about different diseases and genetic disorders. One genetic disorder that has affected the lives of many is, Alzheimer’s Disease. Alzheimer’s is the most common type of dementia that affects and causes problems with thinking, behavior and memory. Most of the time, symptoms of Alzheimer’s develop slowly and progress and worsen over time. Eventually the symptoms become severe enough that they begin to interfere with normal and daily tasksRead MoreSymptoms Of Alzheimer s Disease715 Words   |  3 PagesAlzheimer’s disease has long been considered as a irremediable illness for old people. According to the data collected by Alzheimer s Association(2016), the overall 5.4 million American suffers from Alzheimer s disease, and this population is growing in a certain rate for majority of this population aged 65 and up. Identify possib le Alzheimer’s symptom could be rather difficult because people are lack of the awareness of their implicit illness, which later contribute to the Alzheimer s disease. AlsoRead MoreSymptoms Of Alzheimer s Disease1006 Words   |  5 PagesAlzheimer s disease is a severe illness that affects the brain and leads to gradual memory loss, reduced intellectual ability and deterioration function of thinking. Alzheimer s disease (AD), the most common type of dementia, is a progressive neurological disorder that increasingly robs individuals of cognitive, behavioral, and functional skills (Demakis, 2007). The reason for the appearance this disease is a collection of disorders in the brain due to which its cells are dying partially. In theRead MoreSymptoms Of Alzheimer s Disease2043 Words   |  9 PagesAlzheimer’s disease. It took an emotional toll on me and my family members. I believe Alzheimer is much harder on me and my loved ones than on my grandfather; because he was un aware of what was going on. It’s painful watching my grandfather degrade and get worse each and every day. The worst thing is that he doesn’t even know who I am anymore. In this paper I will discuss certain risk factors, background of Alzheimer’s, Background of Alzheimer’s Alzheimer’s disease was first identifiedRead MoreSymptoms Of Alzheimer s Disease810 Words   |  4 PagesAlzheimer’s disease As the world becomes more happy and joyful, people haven’t stepped into the world of Alzheimer’s yet. Just imagine losing your ability to do normal things you do every day and then you can’t do them anymore. Alzheimer’s is a type of dementia that causes changes and differences in memory, behavior, and how the person’s brain works. The symptoms of Alzheimer’s worsen over time. (Alzheimer’s Association 2015). All of the family members will be affected if one person gets this disease. ThisRead MoreSymptoms And Symptoms Of Alzheimer s Disease1222 Words   |  5 PagesAbstract Alzheimer’s is a disease that attacks the brain and can result in brain death. This disease is chronic and lately a lot of elderly are being diagnosed with it. Alzheimer’s disease can be referred to as a silent killer because once a person gets the diagnosis, they will have it permanently. Alzheimer’s Patients have a decreased short-term memory; this can result with the onset of confusion. At times, families with loved ones that encounter this disease usually have to change their lifestyleRead MoreSymptoms And Symptoms Of Alzheimer s Disease1530 Words   |  7 Pages Hereditary Alzheimer’s Disease Introduction In the year 2015 5.3 million people in the US will have Alzheimer’s Disease. Alzheimer’s Disease, also known as Presenile and Senile Dementia can have a genetic or environmental basis. Alzheimer’s Disease is the most common form of a more general group of memory disorders known as dementia. What differentiates Alzheimer’s from Dementia is how quick the progression of symptoms is. Characterized by debilitating memory loss, confusion, comprehension and

Tuesday, May 5, 2020

Moby Dick Characters of Captain Ahab and Ishmael Essay Example For Students

Moby Dick Characters of Captain Ahab and Ishmael Essay Moby Dick Essays Moby Dick Characters of Captain Ahab and Ishmael The characters of captain Ahab and Ishmael are almost opposites. About the only things the two share in common are that they are both seamen and they both are on a hunt for a whale. Ishmael is a pleasing character, who plays the role of the main character as well as narrator. He is a common man who has a love for the sea, and goes to it to clear his mind whenever he feels down or feels that it is a damp, drizzly November in his soul. As for his physical appearance, he doesnt really specify. However, one might assume that he is a middle-aged man and probably holds the characteristics of the stereotypical seaman. But, what the character lacks in physical description, he makes up for with a full personality that his described extensively throughout the book. Ishmael is a man who seeks what is best described as inner peace. He is very content with himself when on the water, and has a great love for being a seaman. He joins the crew of the Pequod to satisfy his longing to be back on the ocean, but as it turns out, the particular voyage he is to set out on is not what he had suspected. For this ship would be commanded by a half-crazed captain in a desperate search for a viscous white whale. Over all, Ishmael is definitely the most civilized and wise man in the story. Captain Ahab is an overwhelmingly intimidating character in the story, and can probably be considered the most deranged of them all. His radical obsession with finding and killing the white whale known as Moby-Dick causes Ishmael and others of the crew to become frightened at his abnormal behavior. Ahabs physical appearance is best described as foreboding and evil. He is a tall man with gray hair, and is missing a leg due to a death-defying confrontation with Moby-Dick himself. His new artificial leg is made from the bone of whale and once again adds to his intimidating form. His personality is also quite mad. He has a maniacal presence about him and would risk his life and the lives of his crewmen just to fulfill his mission of demented revenge. Melville does a fine job describing this particular character with the utmost extremeness. The characters of Ishmael and Ahab are two that have a great and critical impact on the book. Ishmaels character allows the reader to relate to a love for nature and the earth, as well as a feeling of inner peace and serenity. While on the other hand, Ahabs character is one of chaos and udder madness. The two characters attitudes, thoughts, and feelings permit the reader to explore two polar opposites of the human personality. Ahabs character is critical to the story element in that without him, the reader could not really experience the insaneness of the voyage and the cruelty of the mission that they have set out to accomplish. On the other hand, without the character of Ishmael, the reader would not know how to react to Ahab, and furthermore would only be able too experience one side of the voyage. The reader would be unable to relate to Ahabs demented character, and therefore would have no one in the story to relate themselves to. Ishmaels character gives the reader someone to relate to and identify with. All in all, both characters let the reader better understand the story, and allow for an intense reading experience.

Saturday, April 11, 2020

Environment Essay Example

Environment Essay Name: Tutor: Course: Date: We will write a custom essay sample on Environment specifically for you for only $16.38 $13.9/page Order now We will write a custom essay sample on Environment specifically for you FOR ONLY $16.38 $13.9/page Hire Writer We will write a custom essay sample on Environment specifically for you FOR ONLY $16.38 $13.9/page Hire Writer Environment Argument essay 1 The building of the Keystone XL pipeline has been considered by some as unavoidable. It is a known fact that any pipeline poses significant risks to the area around. Several risks to the environment are raised with the first one already underway. Clearing of forests especially in Canada where the pipeline is expected to pass has already begun. Other risks such as spillage resulting from high pressure are likely to occur every year as some sources cite. The impacts of such adverse risks are hard to recover (Korman 2011). Despite these risks, one side feels that it is necessary to have the pipeline considering the ever-increasing demands of energy. The proponents suggest that the effects brought by the pipeline will not be greater than effects of driving a vehicle every day. Precisely, proponents suggest that, without a near alternative such as enough solar energy, the pipeline is an option that cannot be ignored. While the opponents to the pipeline feel that risks poses are too much t o bear, the main question is whether the current demands or urgency for energy surpasses the need to ensure the soundness of the environment. When one mentions a pipeline, the idea of environmental degradation comes into mind. Almost every person knows that a pipeline would pose a serious danger to the environment. One fact is that completion of this pipeline means clearing an area equivalent to the whole state of Florida or even more. With such a large area to clear, one should consider other environmental effects such as loss of habitat for some wildlife. This further means loss of biodiversity among other effects associated with clearing of forests. This will also see the displacement of many people from their homes and their sources of income. The pipeline poses a risk due to possible spillages. One might say that spills are not likely to happen soon. However, statistical data does prove that, in United States alone, around 50 or more barrels of oil are spilled every three days only from pipelines (Hopkins 2013). With such spills, the environmental pollution is greater and permanent since reversing such damage is quite hard. A recent example of pipeline spillage is the Exxon Mobil pipeline in Mayflower, Arkansas where around 157,000 gallons of crude oil were spilled to the surrounding area. With such risks, completion of what is to become one of the biggest pipelines would mean a greater danger. While the damage to the environment is quite huge and irreversible, the biggest harm comes from what it takes to get oil from the tar sands or bitumen. Unlike other crude oils, it requires three barrels of water for the production of one barrel of oil. The worst part is that, when used, this water becomes contaminated with pollutant chemicals such as cyanide, ammonia and others, making it unusable or unsafe for consumption. This water is later released to the environment, causing increased harm, especially when the tar deposits sink below the water bodies, thereby contaminating them forever. Further, development of oil from tar sands produces three times the amount of greenhouse gases produced by other oil types. This makes it a very unclean source of energy. Such risks are causing many people to oppose the building of this pipeline considering the cost to the environment will be immense. However, some people are for the opinion that the pipeline should be completed. One of the major benefits to the economy is employment to many people especially during construction. Several companies have received contracts from the Canadian company building the pipeline. Proponents do contend to the fact that this pipeline will have unfortunate damage to the environment. However, they cite that urgency should be the main point to consider. While environmental and climatic changes are important, they are not as urgent as the need for energy. Thus, United States should not refuse the oil from Canada. Moreover, realities concerning the current situation in environmental risks caused by burning of fossil fuels involve huge damage to the environment, as well as other forms of energy. â€Å"The idea of turning away the oil from Canada because of its higher greenhouse-gas profile—about 17% higher than other fossil fuels, according to some sources—strikes us as a luxury, not a life-and-death issue† (Korman 2011). In this regard, the proponents to b uilding of the pipeline feel that environmental degradation should not be an issue considering the current demand for energy. Although it is not a life and death issue, environmental degradation costs us future generations, which I consider a matter of life and death. A further argument is made citing that United States and other nations across the whole world will continue to depend on fossil fuel burning for energy in a long time considering there is no close substitute to oil (Korman 2011). This is very true. However, I do not think that this allows us to continue exploiting unclean sources of energy. This implies that, as demands for energy increase, we shall have to keep exploiting such sources of energy while instead we should be seeking cleaner sources of energy. According to Pastel, â€Å"Dams and Diversions now alter the timing and volume of river flow on a wide geographic scale,† (2). In a world where the best action means reducing reliance on fossil fuels and increasing cleaner energy such as solar energy and wind energy, making a decision to continue with production of energy that increases production of greenhouse gases by 17% than usual is unethical. Considering the current issues about environment, increasing environmental degradation on the account of urgency in demand for energy does not make sense. The demand for energy will continue to rise even in the coming future. At this time, the government should be exploring cleaner sources of energy to meet the increasing demands. Continuing with building of the pipeline because of the current urgency for energy at the expense of our environment is not worth especially considering that this could go on for many decades. Instead, the government should start the exploration of newer and clean sources immediately. Argument essay 2 In an effort to meet our needs, we humans have tamed the environment. The environment now comes back with a lash threatening every person’s life. Water is one of the basic commodities without which any living organism cannot live. Yet, water is becoming a precious commodity that many cannot get. It is surprising that in an effort to produce more crops and generate electricity people have constructed dams and dykes on rivers to reduce impact of floods. As usual, changing nature comes with its costs to the same people who changed it. Additionally, human activities continue to make water unsafe for drinking while preventing most of it from flowing to the seas. This has caused serious consequences never foreseen before. Therefore, allowing rivers to flow ensures the maintained health of ecosystem as opposed to stopping water flow through dams and irrigation (International Rivers 2012). While irrigation is necessary for growing food considering that rain is not enough, it comes with costs especially when water is blocked from flowing. Building of dams slows the flow of water and allows creation of sediments or alluvial deposits at the bottom of the dam. With slowed water, breeding of insects such as mosquitoes increases and causes diseases to the people around. Such diseases can be prevented by allowing flow of water down the river. Water is considered life despite being a basic commodity that many take for granted. When dams are built, animals down the river are faced with a hard time. For instance, fish that swim upriver for spawning are blocked. This poses a risk to the extinction of such a species since it cannot reproduce. The sediments trapped at the bottom of the dam are necessary for supporting fertile plain lands downstream, coastal wetlands and productive deltas. Further, people living down stream are faced by huge water crisis when rivers are blocked up stream. The stagnant water changes some of the water properties such as temperature, oxygen levels as well as dissolved chemicals making the water unsuitable for aquatic plants and animals living around the area as well as downstream. Variation in river flow has the greatest environmental impact where life evolves depending on the amount of water flow and sediments transported downstream. Slight changes can change the ecosystem balance and cause change s in aquatic as well as riparian life. Considering these effects of building a dam, it is clear that having one costs the river’s ecosystem. This means that preserving and conserving rivers in their natural form is the best way of ensuring a balance in the ecosystem of the river. The current number of dams and artificial lakes in the United States is said to be more than 2 million small ones and about 75,000 large dams. Many rivers in the United States are dammed some with several dams. Although they are important for farming and hydroelectric power generation, supplying water to people and other places, it is important to consider the environmental impacts. Although we cannot eliminate all dams and reservoirs, we can reduce them to leave those that do not affect the flow of the river greatly. It is not surprising that some lakes that got their water from rivers are shrinking rapidly. Reduced flow of water downstream is reducing the flow of water into these lakes, which further threatens the life of some of the species (Muir 2013). Dams tend to favor predators especially with increase in water temperatures. The reduced levels of water especially near the dams ten to give predators a higher hand. Lack of balance threatens some fish species that swim upriver for spawning. Further, rivers ensure the existence of some places such as wetlands, floodplains and watershed that have their purpose such as absorbing rainwater and slow runoffs, which they help in recharging groundwater. The natural ecosystems have a great value that all people should value. Although damming is not good for the ecosystem, the economy has to be considered. Sometimes such activities have to be engaged considering their value to the economy. For instance, hydroelectric power is one of the clean energies that provide a substantial percentage of electricity worldwide, as opposed to other means such as nuclear power that people would not want near their homes (Postel 2009). Additionally, dams are important for supplying water to the people. However, the dams should only be limited to those that serve such important purposes. Otherwise, those that do not serve such purposes should be removed to allow natural ecosystems to thrive. Dams and reservoirs have their functions in the environment such as supplying water to people, irrigation and production of hydroelectric power. Although many purposes exist including entertainment, I feel that the three are the most important that can be allowed to exist since they support human life. Other purposes that might not be so significant should not hinder the flow of rivers downstream (Pastel 2). However, despite the purpose of a dam, water should continue to flow downstream in order to support the life downstream to avoid the adverse effects of varying flows down the river threatens the lives of both animals and people living in the lower areas. Work Cited Hopkins, Ruth. Keystone XL equals Death., April 30, 2013. Web. July 2, 2013. International Rivers. Environmental Impact of Dams., 2012. Web. July 2, 2013. Korman, Richard. â€Å"Building the Keystone XL pipeline: A Necessary Evil.† Engineering News-Record, 267.11 (2011): 104. Print. Muir, John. Dams and Rivers: Human and Ecological Consequences., February 12, 2010. Web. July 2, 2013. Postel, Sandra. â€Å"Water for Life.† Guest Editorial, Frontiers in Ecology and the Environment, 2009. Print.

Tuesday, March 10, 2020

Marine Biodiversity essays

Marine Biodiversity essays If New Zealand had no restrictions or control over the fishing industry, then fish might start appearing as a rare species on cute-endangered-animal posters. By government control of fisheries, we can help to ensure the future biodiversity of our waters. Biodiversity means having a large range of organisms living in an area. This is important for keeping a large range of fish and wild organisms in New Zealand seas. By controlling commercial and recreational fishing, the government can help to maintain biodiversity. For this reason in June 2000, the government allowed $14.1 million to go towards research for increasing our insight into marine ecosystems. A range of laws are set down by the Ministry of Fisheries help to regulate fishing. The key to this is the 1986 Quota Management System, introduced for the management and conservation of commercial fisheries. There are rules such as closed areas and seasons for different species fishing, fish size limits, mesh size limits for trawler nets, trawling area restrictions and total volumes allowed to be caught. These volume regulations are the Total Allowable Catch (TAC), which limits numbers of fish that can be caught by fishers and the Total Allowable Commercial Catch specifically for commercial volumes. The TAC is re-evaluated and determined each year through scientific research into the abundance and survival of different fish species. There are also restrictions for recreational fishing, because these fishers have almost as much impact on fish populations as commercial fishers. The rules for recreational fishers include things such as size restriction: in the North Island snapper shorter than 27cm long must be thrown back; bag (volume) limits, net size limits, controlled areas and not selling or trading catch. Gear restrictions also apply for things like the size of net mesh and lobster pots. Infringement fees are the penalty for anyone ...

Saturday, February 22, 2020

Discuss the history and evolution, justifications for, and ultimate Essay

Discuss the history and evolution, justifications for, and ultimate impact(s) of Canadian content regulations in Canadian radio and television broadcasting from the industrys inception to the present - Essay Example the region’s largest media producer, Canadian broadcasting systems have found it cheaper and more convenient to buy popular American music and programs packages as opposed to creating original Canadian content. In response to this, the Canadian Broadcasting Act created regulations and specifications that Canadian programming broadcasters had to meet and fulfill. The aim with this was to raise viewership of Canadian content with the intent to promote national identity and increase support for Canadian talent. The final essay will have a dipper analysis of the Broadcasting Act, Section 3(1) that sets out the general requirements for the broadcast of Canadian content. The Canadian Radio-television and Telecommunication Commission is a key player in terms of broadcasting policy, ensuring that private and public broadcasting systems follow the requirements of the Broadcasting Act for Canadian programming. The essay will also explain the way in which the MAPL system is used to categorize which music is Canadian as well as the detailed airtime requirement for radio and television and what a program must do to get classified as a Canadian program. The Canadian Broadcasting Corporation will be presented as an example of Canada’s national public broadcaster, which follows the requirements set for ‘Canadian content’ on radio and television. According to Armstrong (2010), in 2007-2008 the CBC aired 81 per cent Canadian programming during its primetime (p.116). The Broadcasting Policy in Canada and other readings in the course kit will provide a general idea about creation of radio and television broadcasting as well as serving as a guide to the changes that Canadian broadcasting went through. They will also help in taking a look at the different commissions that were established in order to make recommendations on Canadian broadcasting system. The use of outside sources such as journal articles by Johansen, Boardman and Vipond will allow an in-depth look into the