Abiotic and Biotic Stresses

Abiotic and Biotic Stresses What causes a plant to be stressed? As with humans, stresses can originate from the surrounding environment or, they can come from living organisms that can cause disease or damage. Water Stress One of the most important abiotic stresses affecting plants is water stress. A plant requires a certain amount of water for its optimal survival; too much water (flooding stress) can cause plant cells to swell and burst; whereas drought stress (too little water) can cause the plant to dry up, a condition called desiccation. Either condition can be deadly to the plant. Temperature Stress Temperature stresses can also wreak havoc on a plant. As with any living organism, a plant has an optimal temperature range at which it grows and performs best. If the temperature is too cold for the plant, it can lead to cold stress, also called chilling stress. Extreme forms of cold stress can lead to freezing stress. Cold temperatures can affect the amount and rate of uptake of water and nutrients, leading to cell desiccation and starvation. Under extremely cold conditions, the cell liquids can freeze outright, causing plant death. Hot weather can affect plants adversely, too. Intense heat can cause plant cell proteins to break down, a process called denaturation. Cell walls and membranes can also melt under extremely high temperatures, and the permeability of the membranes is affected. Other Abiotic Stresses Other abiotic stresses are less obvious but can be equally as lethal. In the end, most abiotic stresses affect the plant cells in the same manner as do water stress and temperature stress. Wind stress can either directly damage the plant through sheer force; or, the wind can affect the transpiration of water through the leaf stomata and cause desiccation. Direct burning of plants through wildfires will cause the cell structure to break down through melting or denaturation. In farming systems, the addition of agrochemicals such as fertilizers and pesticides, either in excess or in deficit, can also cause abiotic stress to the plant. The plant is affected by an imbalance of nutrition or via toxicity. High amounts of salt taken up by a plant can lead to cell desiccation, as elevated levels of salt outside a plant cell will cause water to leave the cell, a process called osmosis. Plant uptake of heavy metals can occur when plants grow in soils fertilized with improperly composted sewage sludge. High heavy metal content in plants can lead to complications with basic physiological and biochemical activities such as photosynthesis. Biotic Stresses Biotic stresses cause damage to plants via living organisms, including fungi, bacteria, insects, and weeds. Viruses, although they are not considered to be living organisms, also cause biotic stress to plants. Fungi cause more diseases in plants than any other biotic stress factor. Over 8,000 fungal species are known to cause plant disease. On the other hand, only about 14 bacterial genera cause economically important diseases in plants, according to an Ohio State University Extension publication. Not many plant pathogenic viruses exist, but they are serious enough to cause nearly as much crop damage worldwide as fungi, according to published estimates. Microorganisms can cause plant wilt, leaf spots, root rot, or seed damage. Insects can cause severe physical damage to plants, including the leaves, stem, bark, and flowers. Insects can also act as a vector of viruses and bacteria from infected plants to healthy plants. The method by which weeds, considered as unwanted and unprofitable plants, inhibit the growth of desirable plants such as crops or flowers is not by direct damage, but by competing with the desirable plants for space and nutrients. Because weeds grow quickly and produce an abundance of viable seed, they are often able to dominate environments more quickly than some desirable plants.

How to Grow a Big Alum Crystal

How to Grow a Big Alum Crystal Alum is found in the spices section of the grocery store. That little jar contains small white crystals that, with a bit of time and effort, you can grow a big alum crystal  that looks a bit like a diamond. This takes days to weeks. What You Need for Alum Crystals 1/2 cups hot tap water2-1/2 tablespoons alumnylon fishing linepencil, ruler, or knife2 clean jarsspooncoffee filter/paper towel Grow the Crystals Pour 1/2 cup of hot tap water into a clean jar.Slowly stir in alum, a little at a time, until it stops dissolving. Dont add the whole amount; just enough to saturate the water.Loosely cover the jar with a coffee filter or paper towel (to keep dust out) and allow the jar to sit undisturbed overnight.The next day, pour the alum solution from the first jar into the clean jar. You will see small alum crystals at the bottom of the jar. These are seed crystals that you will use to grow a big crystal.Tie nylon fishing line around the largest, best-shaped crystal. Tie the other end to a flat object (e.g., popsicle stick, ruler, pencil, butter knife). You will hang the seed crystal by this flat object into the jar far enough so that it will be covered in liquid, but wont touch the bottom or sides of the jar. It may take a few tries to get the length just right.When you have the right string length, hang the seed crystal in the jar with the alum solution. Cover it with the coffee filter and gr ow a crystal! Grow your crystal until you are satisfied with its size. If you see crystals starting to grow on the sides or bottom of your jar, carefully remove your crystal, pour the liquid into the clean jar, and put the crystal in the new jar. Other crystals in the jar will compete with your crystal for alum, so it wont be able to get as big if you let these crystals grow. Crystal Growing Tips You can use sewing thread or other string instead of nylon fishing line, but crystals will grow on the entire length of the submerged string. Crystals dont adhere to nylon, so if you use it, you can get bigger and better crystals.Alum is an ingredient used to make pickles. It makes them crispy.

The reality of Global Warming in the Modern World Research Paper

The reality of Global Warming in the Modern World - Research Paper Example Many techniques have been developed to study how for instance the sea levels have changed over the last few millions of years, even before mankind walked the world. Some of the techniques which have been developed include studying annular rings of old trees, coastal fossils, coral reefs and even fossils in the dry land. Most of these techniques have been used to reveal how climatic change has affected the earth and the life in it, even without the help of the human race. Evidence of coral reefs which have been found in what is now dry land indicates that the coastal lines I most places in the world were further inland. This is evidence that temperature changes can and will lead to changing coast lines and this is a very serious issues for the modern world where big cities have been build on coastlines. There is therefore a need to make sure that these issues are well understood by everyone and that everyone understands what hey need to do. Yet, in the modern world, human activities have increased the rate of climatic change in a very drastic way, making it possible for the climate change to be the fastest in the history of the earth. By studying coral reefs, and coastal reefs, it has been revealed that in the past, coastal levels have been changed a lot leading to the extinction of vitreous specials of both plants and live. In the past, climatic change has been in two ways such as towards receding the coastal line as well as advancing it.

Avatar Essay Example | Topics and Well Written Essays - 750 words

Avatar - Essay Example It is a beautiful story set in the future and teaches people how to take care of resources and minerals while there is still time to do so. The film has been widely acclaimed by most of the world and is also one of the all time best sellers in the box office. Bill Gibron of Film Critic writes, â€Å"At first, Avatar is a bit disconcerting. The lush landscapes, the primeval forests bursting with alien life, the gorgeously lithe Na’vi and their graceful yet strong athletic movements — it’s impossible not to marvel at the creative process involved here.† The movie has taken almost two decades to get out there and has been regarded as wholesome with delicate touches by this particular critic. However, the script has several cheesy dialogues which are predictable and most people think that the silence and music in the movie is what really captivates the audience. The dialogues on the other hand could have been ignored. The performances are extremely solid and within the context. Gibron states that Saldana acted better than even Worthington or Lang in a very stunning manner indeed. On the other hand, another critic from Portland Media Centre writes that the movie was a painful treatise of racism where a white man tries to claim ownership over the last remains of the planet. It talks about acceptance of Jake into the Na’vi society as he wins over even their blood in the end by completely converting into a species of the other form, so that he may win over his lady love, Neytiri. In popular culture this was not accepted by a lot of people and it took over the impressive effects that the movie had to offer. This is because most people understood that one cannot simply give up on their identity in order to grasp another one and at the same time, it is not possible for someone to intrude into another’s society and take over what belongs to them. Thus, this critic has provided the audience with a very sharp take on the film by

The Human Resource Function Essay Example for Free

The Human Resource Function Essay Heathfield (2007) defines Human Resource Management (HRM) as an organizational function; focusing on recruitment, management, and directing the people who work in the organization. HRM can hence be viewed as an organizational function that deals with the human resource â€Å"people who start and operate an organization, (Ramlall, 2003). Owing to the continuous political, economic, social and psychological changes within our societies, there is an increasing need for organizations to constantly evaluate their internal and external environment in response to the challenges and opportunities in the society; so as to remain competitive and to sustain organizational growth. This article examines the strategic role of Human Resource (HR) and its main practices, describes the outcomes of the respective category of (HR) practices and explains the critical reasons for measuring HRs efforts. The fundamental role of the HR to an organization is to â€Å"create value† (Ramlall, 2003) to the organization. It can hence be inferred that the critical HR’s role is to maximize profitability. Every organization, in pursuit of its strategic goals, must determine how particular HR practices correlate with improved business results and be more accountable for each major HR activity. This entails determination of the value of each HR activity in creating a competitive advantage for the organization. Without this, achievement of the organization’s goals and corporate missions may remain a dream that is never attained. There are many factors influencing change in organizational structure today. These factors include technological advancement, globalization, changes in workforce demographics, the elimination of bureaucracies in organizational structures, and the need to strike a balance between work and family issues. Understanding the potential of an organizations resources and optimizing the output of such resources, given the changes, provides an impetus for HR to become the key source of creating the competitive advantage for the organization. It is the role of the HR to build a competitive organization though strategic management of human resources, management of firm infrastructure, management of employee contributions and management of transformation and change. This can be summarized as â€Å"defining the deliverables of work† (Ulrich, 1997). This entails going beyond the strategic business partner role to becoming a player in the business. Ulrich, (1997) identifies six roles of a player in an organization. The player coach, designs, construct, creates followers, plays the rules and changes the organization. This ensures that the functioning of the organization is directed towards its goals. An effective HR personnel acts as a â€Å"facilitator and a collaborator† (Brewster, 2000). As a facilitator, the HR will function as an agent of change- providing rationale, support, and readiness for planned changes designed to support the business strategies. As a collaborator, the HR provides a link between the senior leaders and all employees to implement business strategies forming the strategic link throughout the organization. This is essential to the organization as it helps to maximize its profits. A research by Brewster, (2000) postulates that less than 10 percent of the 968 firms that participated in the study had a formal estimation procedure to measure HRM. This implies that most companies have little or no assessment of their HR department’s efforts and therefore they cannot give any quantitative measures of HRs value to the organization. Hailey, (1999) stated that the best way for HR to gain credibility in order to make meaningful changes is for practitioners to measure the cost and effectiveness of what they do. As such, the HR should be credible enough to lead the rest of the workers towards giving value to the organization. To achieve a competitive advantage, it is necessary to identify the skills that need to be developed internally for current employees and the fundamental areas of effectively managing an organization. The HR function has the most experience and knowledge in addressing these critical issues. It is therefore necessary for an organization to have an effective human resource that can efficiently achieve these vital objectives. The integration of human resources into the organizational strategy provides the basis for enabling the HR function to support and implement the strategic plan to achieve a competitive advantage, (Wofford, 2002). This strategy provides for the maximization of human capital, reduction of wasted and inefficient labor, and other financial investment, eventually to maximize profitability. An efficient HR increases the likelihood of more efficiently achieving the business outcomes and avoiding chaos, massive layoffs, crises resulting from not having skilled employees to carry out particular tasks and not having the right fit among employees, corporate strategies, and business environments, (Hailey, 1999). HR function plays a pivotal role in determining the business strategy through the assessment of the organizations capabilities to compete successfully through a particular strategy, determining the appropriate rewards system, determining appropriate organizational structures, and developing strategies to increase employee performance. All these work in achieving firm’s objectives and assessing the effectiveness of its strategic plan. Given the definition of strategic planning as how an organization will compete, the question arises as to how an organization would be able to assess the effectiveness of its strategic plan. Indicators of a successfully crafted strategic plan include creating advantages that are sustainable over a long period, (Ramlall, 2003). These include attainment of the organizations goals and objectives, the financial profitability of the organization, organizational positioning to create advantages for the short-term and long-term, and creation of a stronger sense of social responsibility. In essence, this process determines the decisions and actions an organization will undertake to create and sustain competitive advantage. It is evident that any organization that endevours to achieve a competitive advantage over its rivals and move towards its strategic goals is left with no choice but to have an effective human resource. The constant evaluation of the effectiveness of the organization results in the need for the HR professional to frequently champion change. Both knowledge about and the ability to execute successful change strategies make the HR professional exceptionally valued. Knowing how to link change to the strategic needs of the organization will minimize employee dissatisfaction and resistance to change. Only an effective HR can champion these important changes.

The Midwife :: essays research papers

The Midwife’s Apprentice is written by Karen Cushman. The setting takes place in the past nearly five hundred years ago from now. It is also a fiction book   Ã‚  Ã‚  Ã‚  Ã‚  Alyce formerly known as Beetle or Dung Beetle has found a home in a village with a Midwife who feeds her only morsels of what hard work she does. But before that the tale of how she was found must be told.   Ã‚  Ã‚  Ã‚  Ã‚  Beetle found herself snug as a bug in a dung heap. She slept for warmth, completely dismissing the horrid smell of it. Then a sharp question asked â€Å"You girl. Are you alive or dead?† she promptly opened her eyes and was taken in after tell the woman she could do hard work and not eat much. So that’s how she ended up as where she is.   Ã‚  Ã‚  Ã‚  Ã‚  Well the midwife didn’t really treat her as an apprentice for she spoke unkindly and forbid that Alyce would ever see what she was helping women do. But Alyce did! And how horrible it was, the Midwife would scream, curse and slap the poor women until they could take no more and push out the baby.   Ã‚  Ã‚  Ã‚  Ã‚  Once the midwife was not there and Alyce had to help the woman with the baby. She told the husband to brew whatever was needed to help her. Then she began talking to her softly and soothing her till the baby came out into the world when it was almost certain that it would not make it. When the midwife got there she was thoroughly mad. The husband of the wife said Alyce was more kind and efficient and that the midwife was no good.   Ã‚  Ã‚  Ã‚  Ã‚  In the end she fled to a small inn near the village where she saved another baby. The Midwife :: essays research papers The Midwife’s Apprentice is written by Karen Cushman. The setting takes place in the past nearly five hundred years ago from now. It is also a fiction book   Ã‚  Ã‚  Ã‚  Ã‚  Alyce formerly known as Beetle or Dung Beetle has found a home in a village with a Midwife who feeds her only morsels of what hard work she does. But before that the tale of how she was found must be told.   Ã‚  Ã‚  Ã‚  Ã‚  Beetle found herself snug as a bug in a dung heap. She slept for warmth, completely dismissing the horrid smell of it. Then a sharp question asked â€Å"You girl. Are you alive or dead?† she promptly opened her eyes and was taken in after tell the woman she could do hard work and not eat much. So that’s how she ended up as where she is.   Ã‚  Ã‚  Ã‚  Ã‚  Well the midwife didn’t really treat her as an apprentice for she spoke unkindly and forbid that Alyce would ever see what she was helping women do. But Alyce did! And how horrible it was, the Midwife would scream, curse and slap the poor women until they could take no more and push out the baby.   Ã‚  Ã‚  Ã‚  Ã‚  Once the midwife was not there and Alyce had to help the woman with the baby. She told the husband to brew whatever was needed to help her. Then she began talking to her softly and soothing her till the baby came out into the world when it was almost certain that it would not make it. When the midwife got there she was thoroughly mad. The husband of the wife said Alyce was more kind and efficient and that the midwife was no good.   Ã‚  Ã‚  Ã‚  Ã‚  In the end she fled to a small inn near the village where she saved another baby.

Examine different sociological views on the change of child

There is really only two views on the change of childhood and they're ‘The march of progress view and ‘The conflict view' both of which are every different to the other. The march of progress view is the view that the position of children In western societies has greatly improved. Aries and shorter , two sociologists of whom hold a march of progress view, argue that children are more valued , better cared for , are more protected and educated , have better healthcare and have more rights all due to sociological changes throughout history.These Include things such as laws estricting child labour, the establishment of policies controlling at what age a child can do things (such as smoke), the introduction of compulsory schooling (1880) , new child protection and welfare legislations and the growth of the idea of children's rights. Lloyd deMause , a social thinker of whom seemed to hold a march of progress view , said In 1974 that ‘ The history of childhood Is a nightm are from which we are Just recently awakening from'. Other sociologists of whom agree with this argue that this Is because not only has society changed as a whole due to new laws, legislations and iews etc. ut also because families seemed to have become more child centred as well as society as a whole. This Is clear as children are no longer to be seen and not heard as they where in Victorian times. They also argue that children are given a better chance of survival due to the development of proper healthcare and higher standards of living thus making childhood better. Many people hold the conflict view that childhood Is quickly disappearing , Iona ople argues against this as through her lifelong research she has found strong evidence hat there Is a very separate culture between adults and children of which didn't exist 50 years ago.The opposing view to that of the marching progress view is the conflict view. This is the view of which Is , held by feminists and Marxists, that childh ood hasn't improvised. Sociologists of whom hold the conflict view argue that one of the main reasons childhood hasn't improved is due to Inequality between both children and adults. They argue that children from different status's , nationalities , gender , ethnicity and class do not have the same resources , chances or backgrounds herefore leaving them unequal.For example according to Mayer Hillman (1993) boys are more likely to be allowed to cross or cycle on roads, use buses and go out in the dark unaccompanied , whereas Jens Bonke (1999) found that girls do more housework than boys , so much so that in some families girls do five times more than the boys in inequality through ethnicity was discovered by Julia Brannens (1994), she found through her study of 15-16 year old girls that Asian parents were more likely than others to be strict towards their daughters.They also argue that there is also inequality between adults and children therefore causing children to experience more control and oppression to that of a child 50 years ago. March of progress writers argue that adults use this power of inequality to the benefit and protection of children. However , critics such as Shulamith Firestone (1979) and John Holt (1974) argue that many things march of progress writers see as care and protection are in fact Just new ways to to force control and injustice on Modern age children.For example Firestone argues that ‘protection' of hildren from paid work is not a form of protection on a child but in fact a way of keeping them dependant on their parents and forcibly creating a segregation between adults and children, of which again is a form of inequality. Another reason they believe childhood hasn't improved is due to the control children experience. Due to the change in society through history and the segregation between adult and children it is seen that adults have more authority over their children, therefore allowing them to control certain aspects of their lives.Such as the pace/places children are and aren't allowed to go, what their child spends time doing and how much time there child spends doing things, there child's bodies and the ways in which they and other people can touch them and the resources their child receives. For example people are allowed to put signs up saying â€Å"no school children† or can band there child from entering a particular estate or place. They can also disallow there child to go out at specific times or set them a time in which they do distinct tasks such as homework or chores.They can also tell a child how to wear here hair or what clothes they can and cannot wear and they can also disallow a child access to the internet etc. These things alone do not come across as an issue but when put together sociologists argue that these things stops the independence of a child and and can even cause a child to be unhappy. Another thing sociologists argue and that isn't rare is that adult control can often lead to abuse in many levels. This can be in 4 different forms physical abuse , emotional abuse, sexual abuse and neglect all seen even in modern day (Daniel Pelka, Baby P etc. ).Another thing sociologists argue that childhood hasn't improved is the way in which technology has taken over our children's lives even in such a way they are constantly glued to a television or games console. This then effects their behaviours and learning abilities which can lead to loss of imagination, shortening of attention span and may cause confusion with fact and knowledge. Sue palmer also found that there where many concerns with teachers as computer games and television was causing children to become more impulsive and distractable therefore compromising ntellectual,emotional and social development.A particular sociologists Neil Postman believed that childhood was disappearing due due to telivisation unsupervised child hood games and rhymes etc. where disappearing therefore children's child hoods where beginning to fade away. In my own opinion I believe in neither the conflict view or the march of progress view as there is lots of little things you have to take into consideration like the way in which life as a whole has changed , for example the fact that theirs at least a case of murder , rape or abduction on the news every single week.Most parents feel as if they have to protect they're children from this and rightfully so. Although some parents may be stricter with they're children than others and some more over protective they all have they're own personal reasons for that. Some parents are strict because they simply want they're children to succeed whereas other because that's the way in which they where brought up. Some parents are more overprotective than other as they only have one child or simply because they're terrified of the disgusting and horrific things that happen here even in the modern era.On one hand I believe that childhood has improved as children are no longer working from the age of 3 and are now given a chance to mature before being pushed into the world of work. On the other hand I think particular aspects of childhood life hasn't improved as children as still being neglected and abused and are very much so reliant on there parents sometimes when they don't actually need to be , also a lot of independence and freedom is being taken away from children from no fault of they're own. So overall I believe in some aspects childhood has improved in others not so much.