Lab Report Essays

Lab Report Essays Lab Report Paper Lab Report Paper The arm may be a bent portion of the shaft, or a separate arm attached to it. Attached to the end of the crank by a pivot is a rod, usually called a connecting rod. The end of the rod attached to the crank moves in a circular motion, while the other end is usually constrained to move in a linear sliding motion. In a reciprocating piston engine, the connecting rod connects the piston to the crank or crankshaft. Together with the crank, they form a simple mechanism that converts linear motion into rotating motion. Connecting rods may also convert rotating motion into linear motion. Historically, before the development of engines, they were first used in this way. In this laboratory we will investigate the kinematics of some simple mechanisms used to convert rotary motion into oscillating linear motion and vice-versa. The first of these is the slider-crank a mechanism widely used in engines to convert the linear thrust of the pistons into useful rotary motion. In this lab we will measure the acceleration of the piston of a lawn mower engine at various speeds. The results exemplify a simple relation between speed and acceleration or kinematical restricted motions, which will discover. An adjustable slider- crank apparatus and a computer simulation will show you some effects of changing the proportions of the slider-crank mechanism on piston velocity and acceleration. Other linkages and cam mechanisms may also be used for linear- rotary motion conversion and some of these will be included in the lab Abstract The distance between the piston and the centre of the crank is controlled by the triangle formed by the crank, the connecting rod and the line from the piston to the centre of the crank, as shown in [ Figure 1 1. Cappuccino, Natalie Sherman/ 2008/ Pages 74 LAB EXPERIMENT NUMBER 12 The purpose of the Acid fast stain is to identify the members of the genus Mycobacterium, which represent bacteria that are pathogenic to humans. Mycobacterium has a thick, waxy wall that makes penetration by stains extremely difficult so the acid fast stain is used because once the primary stain sets it cannot be removed with acid alcohol. This stain is a diagnostic value in identifying these organisms. MATERIALS: * Bunsen burner * Hot plate * Inoculating loop * Glass slides * Bibulous paper * Lens paper * Staining tray * Microscope METHODS: 1. Prepared a bacterial smear of M. Schematic, S. Erasures, ; a mixture of M. Schematic ; S. Erasures 2. Allowed 3 bacterial slides to air dry ; then heat fixed over Bunsen burner 8 times. . Set up for staining over the beaker on hot plate, flooded smears with primary stain-crystal fuchsia and steamed for 8 minutes. 4. Rinsed slides with water 5. Decolonize slides with acid alcohol until it runs clear with a slight red color. 6. Rinsed with water 7. Countersigned with methyl blue for 2 minutes 8. Rinsed slides with water. 9. Blot dry using bibulous paper and examine under oil immersion * Mycobacterium Schematic * S. Erasures * A mixture of S. Erasures ; M. Schematic RESULTS AND DATA USED: 1. M. Schematic, a bacilli bacteria that colored pink resulting in acid fast. 2. S. Urges, a Cisco bacteria that colored blue resulting in non acid fast. 3. M. Schematic ; S. Erasures resulted in both acid fast ; non acid fast. CONCLUSION The conclusion to the acid fast stain is that S. Erasures lacks a cellular wax wall causing the primary stain to be easily removed during decentralization, causing it to pick up the countersink-methyl blue. This results in a non acid fast reaction, meaning it is not in the genus Mycobacterium. M. Schematic has a cellular wax wall causing the primary stain to set in and not be decolonize; this results in an acid fast reaction meaning it is in the genus Mycobacterium. REVIEW QUESTIONS Question 1: Why must heat or a surface-active agent be used with application of the primary stain during acid-fast staining? Answer: It reduces surface tension between the cell wall of the embarcadero and the stain. Source: Microbiology page 79 Question 2: Why is acid-alcohol rather than ethyl alcohol used as a decontrolling agent? Answer: Acid-fast cells will be resistant to decentralization since the primary stain is more soluble in the cellular waxes than in the decontrolling agent. Ethyl alcohol would make the acid fast cells non-resistant to the decentralization. Source: Microbiology A Laboratory Manual 4th Edition/ James G. Cappuccino, Natalie Sherman/ 2008/ page 79 Question 3: What is the specific diagnostic value of this staining procedure? Answer: Acid-fasting staining represents bacteria that is pathogenic to humans Question 4: Why is the application of heat or a surface-active agent not required during the application of the counter stain in acid-fast staining? Answer: The counter stain methyl blue is only needed to give the stain its color. Source: Microbiology A page 79 Question 5: A child presents symptoms suggestive of tuberculosis, namely a respiratory infection with a productive cough. Microscopic examination f the childs sputum reveals no acid-fast rods. However, examination of gastric washings reveals the presence of both acid-fast and non-acid fast bacilli. Do you think the child has active tuberculosis? Explain. Answer: Yes, the child may have active tuberculosis. Although, acid-fast microorganisms are not easily removed and non-acid fast are. Tuberculosis represents bacteria that are pathogenic to humans, the stain is of diagnostic value identifying these organisms. Source: Microbiology A Laboratory Manual 4th Edition/ James G. Cappuccino, Natalie Sherman/ 2008/page 79 LAB EXPERIMENT NUMBER 13 The purpose of this experiment is to identify the difference between the bacterial spore and vegetative cell forms. The vegetative cells are highly resistant, metabolically inactive cell types. The endoscope is released from the degenerating vegetative cell and becomes an independent cell. MATERIALS: * hot plate * staining tray * inoculating loop * glass slides * bibulous paper * lens paper * microscope 1 . The spore stain (Schaeffer-Fulton Method) is performed on a microscopic slide by making an individual smear of the bacteria on slide and heat fixing until dry. 2. Flood the smears with malachite green and place on top of a beaker of warm eater on a hot plate, allowing it to steam for 5 minutes. 3. Remove the slide and rinse with water. 4. Add counter stain seafaring for 1 minute then rinse again with water and blot dry with bibulous paper. MICROORGANISMS USED: * S. Erasures * S. Erasures B. Rues mix RESULTS/DATA USED 1. B. Cereus- green spores, pink vegetative cells, endoscope located in center of cell 2. B. Cereus S. Erasures- green spores, pink vegetative cells, endoscope located in center of cell CONCLUSION: An endoscope is a special type of dormant cell that requires heat to uptake the primary stain. To make endoscopes readily noticeable, a spore stain can be used. In using a microscope, under oil immersion, you will be able to identify the color of the spores, color of the vegetative cells and be able to locate the endoscope in certain bacteria like S. Erasures and B. Cereus. Question 1: Why is heat necessary in spore staining? Answer: The heat dries the dye into the vegetative cell of the spore. Source: Microbiology Lab Manual, 8th edition, Cappuccino Sherman, p. 85 Question 2: Explain the function of water in spore staining. Answer: The water removes the excess primary stain, while the spores remain green the water nines the vegetative cells that are now colorless. Source: Microbiology Lab Manual, 8th edition, Cappuccino Sherman, p. 85 Question 3: Assume that during the performance of this exercise you made several errors in your spore- staining procedure. In each of the following cases, indicate how your microscopic observations WOUld differ from those observed when the slides were prepared correctly. Answer: a. ) You used acid-alcohol as the decontrolling agent. The alcohol would wash out all coloring from the bacteria. Source: Microbiology Lab Manual, 8th edition, Cappuccino Sherman, p. 5 b. ) You used seafaring as the primary stain and malachite green as the countersink. Seafaring will absorb to vegetative cells and not endoscopes since you need heat for endoscopes to form and malachite green will not absorb without heat but it will to vegetative cells. Source: Microbiology Lab Manual, 8th edition, Cappuccino Sherman, p. 85 c. ) You did not apply heat during the application of the primary stain. Without heat, the endoscopes will not form and it will not penetrate the spore to color the vegetative cell. Microbiology Lab Manual, 8th edition, Cappuccino Sherman, p. 5 Question 4: Explain the medical significance of a capsule. Answer: The capsule protects bacteria against the normal phagocyte activities of the host cells. Source: Microbiology Lab Manual, 8th edition, Cappuccino Sherman, p. 7 Question 5: Explain the function of copper sulfate in this procedure. Answer: It is used as a decontrolling agent rather than water, washes the purple primary stain out of the capsular material without removing the stain bound to the cell wall, the capsule absorbs the copper sulfate and will appear blue. Cappuccino Sherman, p. 88 LAB EXPERIMENT NUMBER AAA The purpose of this experiment is to identify the best chemotherapeutic agents used for infe ctious diseases. S. Erasures is the infectious disease used for this experiment. MATERIALS: * Sense-disc dispensers or forceps * sterile cotton swabs * glassware marking pencil * millimeter ruler Using the Kirby-Bauer antibiotic sensitivity test method is used. This method Uses an Antibiotic Sense-disc dispenser, which placed six different types of antibiotics on an Mueller-Hint agar plate, infected with S. Erasures. The antibiotics are in the form of small, round disc, approximately mm in diameter. The antibiotics are placed evenly away from each other on the S. Erasures infected Mueller-Hint agar plate and incubated at 37 degrees Celsius for up to 48 hours. After the completed incubation time, any area surrounding the antibiotic disc which shows a clearing or an area of inhibition is then measured. Measurements are taken from the diameter of each antibiotic area of inhibition. This measurement will determine which of the antibiotics is best to be used against the specific organism. (In this case, S. Erasures) MICROORGANISMS USED: S. Erasures ANTIBIOTICS USED: Autocratic Erythrocyte Cylindrical Geocentric Fancying Linemen A chart showing the measurements of each antibiotic is used to determine its effectiveness. The three different types of ranges are: Resistant (Least useful) Intermediate (Medium useful) Susceptible (Most useful) The following results are: Zone Size Autocratic mm (Susceptible) Erythrocyte mm (Intermediate) Cylindrical mm (Intermediate) Geocentric mm (Susceptible) Fancying 13 mm (Susceptible) Linemen 21 mm (Susceptible) CONCLUSION: 4 of the 6 antibiotics above can be effectively used against inhibiting this organism (S. Erasures). This information would be passed on to the provider of the infected patient, so the patient can be given the antibiotic chosen by their provider and recover from this infection. LAB EXPERIMENT NUMBER BOB The purpose of this experiment is to evaluate the effectiveness of antiseptic agents against selected test organisms. MATERIALS: The materials used are five Traipses soy agar plates. 24-48 hours Triplicate soy broth cultures of E. Coli, B. Cereus, S. Erasures and M. Specialist. The microorganisms used were E. Coli, B. Cereus, S. Erasures and M. Specialist. The data collected in this experiment shows chlorine bleach having the broadest anger of microbial activity because it has the strongest ingredients. Tincture of iodine and hydrogen peroxide seems to have the narrowest range because the contents arent as strong. CONCLUSION: The Agar Plate-Sensitivity Method shows the effectiveness of antiseptic agents against selected test organisms. The antiseptic exhibited microbial activity against each microorganism. Question 1: Evaluate the effectiveness of a disinfectant with a phenol coefficient of 40. Answer: A disinfectant with a phenol coefficient of 40 indicates the chemical agent being more effective than the phenol. Source: Microbiology A Laboratory Manual 4th Edition/ James G.