Blood Buffer Essay

Objectives: After completing this exercise and reading the corresponding material in your text, you should be able to 1. Prepare a wet mount slide 2. Identify structures described in this lab on slides 3. Cite examples of the wide diversity of cell types 4. Relate differences in structure among cells to functional differences Introduction Structurally and functionally, all living things share one common feature: all living organisms are composed of cells. The development of this concept began with Robert Hooke’s seventeenth-century observation that slices of cork were made up of small units he called â€Å"cells.† Over the next 100 years, the cell theory emerged. It was formally (and independently) presented by Schleiden and Schwann in 1839, and clarified by Virchow a few years later. This theory has three principles: (1) All organisms are composed of one or more cells. (2) All life processes derive from the activities of cells. (3) All cells arise from preexisting cells. Living organisms are composed of one or many cells, and every activity that occurs in a living organism is ultimately related to metabolic processes in cells. Understanding the processes of life requires an understanding of the structure and function of the cell. Although cells vary in organization, size, and function, all share certain structural features. All are enclosed within a plasma membrane, defining the boundary of the living material. All contain a region of DNA (deoxyribonucleic acid), which forms the genetic code. Inside of the plasma membrane is watery cytoplasm, and the chemical processes inside the cell occur within this watery medium. Upon microscopic examination, we see there are two basic types of cells, prokaryotic and eukaryotic, see the table below to see a comparison of the two cell types. For these following exercise you should use the highest magnification possible, because you will be able to see more detail, and you should record your observations at this magnification. Always begin with the lower magnifications, once you have found your specimen center it and focus it before increasing the magnification. We will not be using the 100X objective because it requires special handling and immersion oil, so you should use the 40X objective for most observations. What is the total magnification of a sample view with the 40X objective? Remember there is a lens in the ocular that magnifies the image 10x, so the total magnification will be 40 x 10 = 400X. Exercise 1: Examining Prokaryotic cells 1. What types of organisms are prokaryotic? 2. What structures are found in a Eukaryotic cell that will not be visible in a Prokayotic cell? 3. Examine the specimens available at the back of the classroom. Locate a prokaryotic cell and bring it back to your microscope. Name of specimen: ____________________ 4. Examine your specimen under the microscope. Sketch your specimen under 40x magnification below. Be sure to label any internal or external structures visible. Exercise 2: Examining Eukaryotic cells The cells on which we focus most of our attention are relatively large and complex, although many details of their structure are only evident with electron microscopy. The word eukaryote derives from the visible nucleus found in most of these cells. No one cell will show all of the features that a cell might have, so you will be observing a variety of eukaryotic cells. Protist cells: The protist kingdom includes eukaryotic unicellular forms (e.g., protozoans, algae, slime molds) as well as some simple multicellular forms. Many are mobile; some are photosynthetic; others are animal-like, ingesting food particles, or fungi-like, secreting digestive chemicals into the environment. Protists are diverse, often having complex cells. 1. What structures do you expect to see in these cells that was not evident in the prokaryotes you saw? Cultures of mixed protists and/or pond water are available in lab. Many different forms may be found in these cultures, including amoebas, flagellates and ciliates. (Many classifications of protists are based on how they move – with flagella, or cilia, or neither of these.) 2. Examine the specimens available at the back of the classroom. Locate the cultures of protist cells. You will examine two separate cultures. One of the cultures you’ll examine is the â€Å"Mixed Pond Protists,† you can pick which specimen you’ll examine for your second sample from the other cultures present in class. Make a wet mount of each culture, drawing material from the debris at the bottom of the culture jar. Name of specimen #1: Mixed Pond Protists Name of specimen #2: ____________________ 3. Observe first with scanning power (4X objective), looking for movement. If you don’t see anything, wash the material back into the jar and get another drop. Once you have located organisms, observe on higher power (40X objective). If the protists are moving very rapidly, they may swim out of the field of view. In this case, remove the coverslip and add a small drop of Detain. Detain is a thick solution that will help slow down the protists. REMEMBER THAT THE MICROSCOPE LIGHT IS HOT. Turn it off when you are not looking at the slide. 4. Examine your specimen under the microscope. Sketch each specimen under 40x magnification below. Be sure to label any internal or external structures visible. 5. What evidence do you see that protists are eukaryotes? 6. Attempt to identify the protists you have observed. There are several keys to protists available. Your instructor can help you use the keys if you’re not familiar with how they work. Write the name of your protists and your rationale for identification based on the characteristics in the key into your notes. When you have finished looking at your slide, place the slide in the bleach water. Plant cells: Plant cells are different from animal cells in many ways. 1. Name three ways plant cells differ from animal cells below. As in animals, cells of plants are organized into tissues, aggregations of similar cells performing a common function in a multicellular organism. In this part of the lab, you will look at several types of plant cells. Onion epidermal cells: 1. Make a wet mount of a colorless scale of an onion bulb by peeling the thin, membranous layer from the inside of one of the bulb scales and placing it on a slide in a drop of water. This usually works best if you partially slice through a ring, allowing the thin layer of tissue on the inner surface of the leaf to be pulled off. Use forceps to arrange the tissue in a drop of Iodine on a slide and cover with a cover slip. 2. Observe your preparation with the microscope, focusing first with the scanning power objective. Continue your study, switching to the low power (10 X) and finally the high power objective (40 X). 3. What shape do most of these cells have? What structure maintains this shape? 4. What structure is stained by the iodine? 5. Examine your specimen under the microscope. Sketch each specimen under 40x magnification below. Be sure to label any internal or external structures visible. 6. Which cellular components present in most leaf cells are absent from onion leaf cells? Elodea leaf cells: 1. Remove a single young leaf and prepare a wet mount. Examine the leaf first on scanning power, then on low power. 2. Examine your specimen under the microscope. Sketch each specimen under 40x magnification below. Be sure to label any internal or external structures visible. 3. After the cells have warmed a bit from the light of the microscope, you may see cytoplasmic streaming. Microfilaments in the cytoplasm are thought to be responsible for this intracellular movement. What cellular structure do you see moving around the cytoplasm? Animal cells: Human epithelial (cheek) cells: 1. Using the broad end of a clean toothpick, gently scrape the inside of your cheek. Stir the scrapings into a drop of saline and a drop of Methylene Blue on a clean microscope slide and add a cover slip. Do not reuse your toothpick. DO NOT PUT IT BACK WITH THE CLEAN TOOTHPICKS AND DON’T LAY IT ON THE TABLE. Discard it in the BIOHAZARD bag. 2. Because the cells are almost transparent, decrease the amount of light entering the objective lens to increase the contrast. Find the cells using the low power objective of your microscope, then switch to the high power objective for detailed study. Find the nucleus of a cell. Many of the cells will be folded or wrinkled due to their thin, flexible nature. 3. Examine your specimen under the microscope. Sketch each specimen under 40x magnification below. Be sure to label any internal or external structures visible. 4. Dark specs on the cells are bacteria, similar to the E. coli you looked at earlier. How big are these bacterial cells relative to your cheek cells? Discard this slide into the bowl containing the bleach water. Sheep’s blood (wet mount): Blood consists of two parts – a liquid portion (water + proteins) called plasma, and a cellular portion, containing many different cell types, including erythrocytes or red blood cells (RBCs), and leukocytes or white blood cells (WBCs). Red blood cells are red because they contain a lot of the oxygen-carrying molecule hemoglobin. The blood sample we have has been treated chemically to prevent clotting. 1. Prepare a wet mount by placing a drop of saline and a small drop of blood on the slide. Add a cover slip. Examine a portion of the slide in which the blood is diluted. 2. Examine your specimen under the microscope. Sketch each specimen under 40x magnification below. Be sure to label any internal or external structures visible. 3. What is missing from these cells that is found in eukaryotic cells? 4. How do the red blood cells compare to your cheek cells in size? What shapes are the cells? Discard this slide into the bowl containing the bleach water. Cells Review Questions Your answers should be specific and to the level of the lecture, book and lab manual. You may need to use outside sources. 1. What characteristics do all cells have in common? 2. What characteristics are common to all eukaryotic cells but not found in prokaryotic cells? 3. Would you expect that all the living cells you saw in lab contain mitochondria? Explain. 4. Did all living plant cells you observed contain chloroplasts? Explain. 5. Describe as many differences as you can between plant and animal cells at a cellular level. Do any of these differences relate to the organismic differences we see between plants and animals? Explain. 6. How do prokaryotic and eukaryotic cells compare in size? 7. How would you compare a protist cell to a cell from your body, a cheek cell for example, in terms of complexity at the cellular level?

Accounting Equation Paper Essay Example for Free

Accounting Equation Paper Essay ? The basic accounting equation is: Assets = Liabilities + Stockholders’ Equity. When looking at the balance sheet one can assume that assets must balance out each transaction and balance the claims to the assets (Kimmel, 2010). A balance sheet provides Assets of the company first and foremost, then Liabilities and Stockholders’ Equity and last retained earnings. This shows the companies incoming money, outgoing payments, and the money left or retained at the end of each time period being documented on the balance sheet. The components of the accounting equation affect each other in many ways. For example, when cash assets are received the company is making profit only as long as it is making more revenue than the liabilities owed. So, when using the Sierra Corporation on pg. 14 from the text the company has to pay the Liabilities: Notes payable, Accounts payable, Salaries payable, Unearned Service revenue, and Interest prior to ever turning a profit above the black. When looking at a balance sheet one needs to know all incoming as well as outgoing money to determine profitability and sustainability of a corporation. Next, when looking at a balance sheet the liabilities + the stockholder’s Equity have to ALWAYS balance out to amount of assets to ensure all things are accounted for and there are no accounting errors. When done properly the balance sheet can be used to verify the company’s revenue and the financial stability of a company based upon debt to stockholders’ equity. References: Kimmel, P. D., Weygandt, J. J., & Kieso, D. E. ( 2010). Financial accounting: Tools for business decision making (6th ed.). Hoboken, NJ: John Wiley & Sons. Accounting Equation Paper. (2016, Dec 10).

Hacker Target and Response Assignment Example | Topics and Well Written Essays - 1500 words

Hacker Target and Response - Assignment Example The principal objective of this paper is to identify the areas and the information that an attacker might want to obtain and the methods that they may employ in undertaking the criminal activity. The paper also seeks to highlight the possible damage that their activities may cause to the information system. It is also important to show the preventive measures and the appropriate responses towards the security threat. As said earlier in the paper, one of the probable offenders is an ex-employee of an organization. The reason for this is that the ex-employee might have negative motives of releasing sensitive information that could destroy the reputation of the organization. The primary objective of an ex-employee would be to revenge. Another area that could be attacked by the ex-employee is the financial security system. The offender could have an objective of crumbling the organizations financial stability. The terminated employee may also target the organization’s foundational information, its economic weaknesses, production information and organizational information (Covaleski, 2013). There are multiple ways in which the terminated employee may use to hack into the company’s information system. One of the ways is using other employees to obtain information; the other means they could employ is to use their knowledge of security passwords and access the organization’s information system. A well-planned data security strategy alternatively posits the objectives of the information system of a business and formulates a plan to attain these goals (Dhillon & Backhouse, 2000). Any leakage of sensitive corporate information is a pragmatic basis of corporation collapse. Precisely the data system lacking a prolific information security is prospective to be a separate collection of check procedures that include numerous severe security threats. Information systems security policies at that instance may frequently be

Interventions to reduce harm associated with adolescent substance use Essay

Interventions to reduce harm associated with adolescent substance use - Essay Example that reduce harm associated with adolescent substance use are because the disease burden and deaths for young people in developed nations is attributed to substance use. The interventions are about to reduce harm. In this course, they have to reduce mortality in the future and morbidity in the short period. The interventions are subjected to review to know about the impact of them on the persons. The positive impact of the intervention is a scale of its efficacy. In order to prevent the attractiveness to substance use, the regular interventions are necessary to avoid the adolescents in vulnerable families, schools and communities being attracted to substance use. However, there is little evidence found in study of JW Touymbourou et al in 2007 that tells about efficacy of treatment. However, they have found that the screening and brief interventions are effective. (J W Toumbourou, 2007, p.1391) This indicates that treatment approaches need long term approach than to observe in a limited time of study. This needs the feedback from the counselors who treat people suffering from substance abuse. They are effective in many contexts because, these reduce the availability of these drugs to majority of adolescents and are universal interventions. However, the efficacy of targeted interventions is more important as it is capable of addressing the problems personally. In contrast to regulatory interventions, the development interventions are more targeted than being universal. These interventions target the reduction of pathways to drug related harm by enhancing the conditions for healthy development of a person through his/her adolescence. Even in these interventions, there are two types. They are the ones that begin before the birth of a person and others are the ones, which are taken in the early stages of adolescence. The interventions before birth proved to be effective. (J W Toumbourou, 2007, p.1395) However, there are second types of interventions that start

Envisioning America & What Caused the Pueblo Revolt Essay - 8

Envisioning America & What Caused the Pueblo Revolt - Essay Example I myself have been witness to some of those distressing racial atrocities and have seen murderous intent of few white who had applied Jim Crow Rules against the blacks. I still feel ashamed of the stunted mentality of those people who reveled in the killings of another human being! America was discovered by Spanish explorer, Columbus in the 16th century, who had developed good relations with the native Indian population. But the early 17th century saw the process of colonization by the British settlers who had brought shipload of African slaves as bonded labors to work on plantation and elsewhere. Jamestown in Virginia became the first place for British settlement followed by colonies in Massachusetts and eastern seaboard in the later part of the century. They also tried to exploit the Native Americans with respect to labor and sea faring activities. The indentured labor consisting of European workers, worked as bonded laborers who were freed after several years so as to pay-off their passage to a new country. The slaves worked in labor intensive tobacco plantations along with Native Americans who later refused to work because they were afflicted with diseased like tuberculosis etc. which were brought by the settlers. Turn of the century saw the raced based slavery becoming a full fledged tradition with Africans and non whites becoming slaves for life. Control over the blacks became the main concern of the white because of the rebellion from the natives. The British Crown delegated the power to the companies who administered in their behalf with rules and regulations. The natives, on the other hand, did not believe in subjugation and rebelled against any revenue imposed by the settlers. I had a fat black lady as my governess who was not only very loving and funny but she was also ferociously protective of me. I remember that once when my parents had to leave in emergency, my Joan, my governess took me to her place for

The Importance of Recruitment and Selection in Public Sector Business Essay

The Importance of Recruitment and Selection in Public Sector Business - Essay Example 2. Recruitment and Selection are two different but related terminologies. This project shall therefore be an opportunity of identifying the difference that exists between these two terms and how each of them contributes to the success of the organization. 3. Through this project, the research shall seek to look into the difference between processes and merits of recruitment private sector and public businesses though the public sector shall be made the experimental sample. 4. Within the public sector business, the researcher shall scrutinize various reasons why human resource managers undertake recruitment and selection on regular basis. 5. Clearly, the various merits or importance of recruitment and selection cannot be realized if certain factors are not adhered to. Through this project therefore, the researcher shall find out the various factors that human resource managers within the public sector business setup must stick to in order to ensure that they benefit from the importanc e of recruitment and selection. 6. ... LITERATURE REVIEW Having noted that human resource personnel in the public sector have always been involved in recruitment and placement, one is left with not more than to ask of the importance of recruitment and placement in the public sector that human resource personnel cannot seem to stop the practice. There indeed exists a number of importance of undertaking recruitment and placement. Five major reasons, merits or importance behind recruitment and selection in the public sector have been discussed below. Satisfies Legal and Social Obligations of Organizations The first importance of undertaking recruitment and selection in the public sector is that it is a process that goes a long way to satisfy the legal and social obligations of institutions. International and various labor laws provide that public institutions make their placement processes very fair and open. For that matter, placement must be done only after certain stipulated guidelines have been fulfilled (Gilmore and Wil liam, 2009). In labor provisions, undertaking recruitment and selection is the legally mandated means to get employees to occupy vacancies. By undertaking recruitment and selection therefore, public organizations are getting themselves out of legal entanglements and fulfilling their social obligations of making the lives of deserving skilled and unskilled personnel better (Thompson and McHugh, 2009). Previously, activities of public sector managers regarding placement was not seen as a social task but strictly business and corporative. Today, it has come to be accepted that there could not be any better way for public institutions to be socially responsible to the people than employing as many deserving people as possible (Arnold, J. et al 2005). This is because research has

Logistics & Physical Distribution Essay Example | Topics and Well Written Essays - 2250 words

Logistics & Physical Distribution - Essay Example The key components of the paper involve company description, supply chain mechanism, key performance indicators, charts and diagram of supply chain and applicable support systems such as ERP, SCM, and APS. My supply chain design of the company ABC is aimed at ensuring that time for clearance and distribution of goods at port is minimized. This paper addresses the design and operation of company ABC in terms of its supply chain. Key Performance indicators (KPI’s) in terms of supply chain of the company ABC concerns improvement of time usage at ports (Kapoor and Kansal 2003). Diagram and charts providing the logistics and physical distribution of the ABC are essential for effective presentation of the strategy. Physical distribution comprises the movement, handling, and storage of products from the point of source to their tip of consumption or employ, via various routes of distribution. Logistics administration comprises the management of these functions for competent and expenditure successful physical distribution. It must be apparent the last 50 meters are fitting more and more leading in these kinds of supply chains. Supply chain organization is the lively administration of supply chain actions to exploit customer value and accomplish a sustainable aggressive advantage. The objective of Company ABC is to increase efficiency through elimination of redundancy distribution and supply processes that are used in many clearance and forwarding organization. The goals of supply chain management are to minimize and reduce organizational inefficiencies. In order to employ this in company ABC’s supply chain, it is necessary to analyze the process of organizing practices among production facilities, suppliers, customers and distribution centres. This will enable a precise distribution of goods at the right time to the correct destination. By doing this, it would be possible to reduce costs while sustaining a desired service level. After assessing the objective of