Scientific Methodology : 5 Second Rule Experiment Lab Report Make sure each of t

Question

Scientific Methodology :

5 Second Rule Experiment Lab Report

Make sure each of the bold parts below are used as section headings in your lab report. The writing should be in a 12 font double-spaced and should not be longer than two to three pages (not including the tables).

Name: [Insert your Name Here]

Section: [Insert your Section Number Here]

Signature   ___________________________________    

Title:

(3 pts for name and creative title)

Introduction (7 pts)

In one large paragraph include the following:

Use references and provide three pieces of background information on the general characteristics of bacteria.

Then clearly state the hypothesis and prediction of your 5 sec drop experiment.

Use one or two sentences to connect your background information with the importance of your hypothesis and your prediction for the experiment.

Materials and Methods (5 pts)

Include Table 6

In a few sentences describe exactly how sampling was done for Part III and the conditions of incubation

Results (10 pts)

Results of Part II: Include the total number of colonies, and total number of different types of colonies that grew on each of the agar plates if possible.

Include Table 7, Hemolysis results table, and/or any other tables

Include drawings or photos

Describe what the bacterial growth looked like on each of the plates in general terms in a paragraph and make sure to refer back to your drawings or photos.

         

Discussion (12 pts)

Summarize the purpose of the 5 second rule experiment based on background information that you researched and read in two sentences.

Describe how the results supported or did not support the hypothesis and your prediction. Refer to data from the Results to do this. You may also need to explain why results were inconclusive. Don’t forget to compare the experimental plates to the controls (1 or 2 paragraphs).

Describe any problems with observing and quantifying the bacteria colony growth on the different plates in a sentence or two.

How do you think the properties of the food you tested affected this experiment? What other factors affected the results of this experiment? If you could repeat your experiment, what would you change or improve? (three sentences total)

Different species of bacteria have growth requirements that are specific to their needs. The needs vary greatly because bacteria grow everywhere from the hot springs of Yellowstone to even snow. Based on this perspective, do you think the same types of bacteria grew on the nutrient agar as the blood agar, why or why not? Do you have any proof of this from your experiment? Explain in a few sentences.

In a couple of sentences, write a conclusion about the 5 second rule in terms of what you learned from this experiment.

References (Minimum of 3 and don’t forget to cite them in report text) (3 pts)

NOTE>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

use this table as well and solve all parts otherwise don't do it

gummy bear Part II: Results and Conclusions Record data in the table below. Take pictures of your plates using your phone (be careful!). Make a conclusion about your results. Did the able that you tested alter the number, diversity, type of bacterial colonies? Any additional of different Total of Colonies colony types based results Agar Type Plates on morphology hemolysis Nutrient 1: first half translu on Nutrient 1: second half 2: first half Tetracycline A 2: second half Tetracycline Blood 3: first half Circ, lar Moderate ref trans uarto Blood 3: second half Nutrient 5 Control Tetracycline Blood 6: ITA) 35

Explanation / Answer

Name: [Insert your Name Here]

Section: [Insert your Section Number Here]

Signature:

Tittle:

The 5-second rule: How fast you should pick up your dropped food.

Introduction.

The microbes are ubiquitous organisms. They are present in air, in water and also on the floor. They are found in soil, plants, animals, in radioactive waste, water, arctic ice, glaciers, hot springs…etc. Tonnes of bacteria live in close groups, for example, one gram of soil contains at least 40 million bacteria. According to 2004-2012, MediLexicon International LTD, around 5 x 10^13 bacteria dwell on earth. Bacteria decompose and break down elements in living or dead organisms, and also in the soil they decompose matter and recycle carbon, nitrogen, sulfur, and other chemical elements (1989, World Book, Inc.).

Many times we pick up the dropped food and eat it without even thinking that the microbe present on the floor might have attached to your food. That contaminated food may enter your stomach and cause gastrointestinal problems. To find out what is the minimum time we have to pick up the fallen food from the surface of floor or a table, a hypothesis is developed, and it is called 5-second rule. It states that food dropped on the ground will be safe to eat and not covered in germs as long as it is picked up within 5 seconds of being dropped. This experiment will evaluate whether there is any truth to this theory.

Materials and Methods

Agar plates (nutrient agar, nutrient agar with Tetracyclines, Blood agar). Laminar air hood.

The plates (mentioned above) were prepared by autoclaving. The Tetracycline was added during plating. The plates after solidification were exposed to the surface/air ( Please write what you did in the lab) at different times ( 5sec and 30 sec). Later the plates were closed and incubated in 37C incubator for 24 – 48 h (Lehman. C]. The colonies were visualised and counted.

Results

The results of the test were noted after the incubation period of 24 – 48 h. The nutrient agar plates exposed to 5sec had 3 colonies, whereas the one exposed to 30sec had no colonies. The colonies from 5sec plate had 2 overlapping colonies circular in shape. The haemolysis results showed pigmentation of colonies either white or grey. And the colonies were translucent.

The antibiotic plate exposed to both 5sec and 30 sec showed no colony growth and hence no hemolysis. The 5sec exposed blood agar also had no colonies. The 30sec exposed blood agar plate showed 1 circular colony with moderate size. The hemolysis results were grey translucence colony.

All the control plates which were not exposed were sterile with no colony growth.

Discussion

The 5 second rule is hypothesized to determine the minimum time we got to pick up any dropped food and exposed media. It can be used in home also in lab.

The results from our study, however, contradicted the above rule. The 5sec exposed plate had 3 colonies and they were beta haemolytic ( complete hemolysis). These colonies belong to streptococci group [Ray et al].

The 30 sec exposed plate had no colonies at all. These results do not follow the 5 second rule. There was no difference in control plates and to the test plates in most of the cases. However, our results are inconclusive due to lack to technical and biological replicates. At least 3 technical and 3 biological replicates are needed to prove or disprove any hypothesis. The property of the food also determines the rule. If the food is sticky, jelly or liquid it is bound to pick up more dust and more microbes. On the other hand, if the food in dry chances of microbes sticking on it a low The colonies were not very small and there was no problem in observing them. The properties of the food also play a role in the experiment. The bacteria occupy various regions and various locations, like hot springs, cold arctic..etc. In our lab set up, such bacteria were not isolated. To grow such bacteria their innate temperature and other conditions must be provided.

Thus the 5second rule is not universal and our results show that the 5 second rule is not scientific.

References:

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