INTERNAL ASSESSMENT
AIM: I want to investigate bacteria reaction to savlonHYPOTHESIS: I predict that the savlon will leave a circle to where the bacteria have been killed. I predict this because the savlon in a disinfectant that should kill bacteria in the affected area.
PURPOSE: The purpose of this experiment is to see the effects dettol have on bacteria. And how much bacteria each concentration kills.
VARIABLES:
1.The independent variable that I will be changing is.
EQUIPMENT:
-Agar plate -bunsen burner -pen -cotton bud -yoghurt -savlon -stopping tile
-pipette -hole punch -filter paper -tweezers -ethanol -tape -water - beakers
METHOD:
1.label the agar plate into four sections
VARIABLES:
1.The independent variable that I will be changing is.
The independent variable that we are changing is the concentration of the savlon added to water to kill the bacteria. The consecration of the dettol was
0% - 0:10 -ten drop of water and zero drops if savlon
10%- 1:9- nine drop of water and one drop of savlon
50%- 5:5- five drop of water and five drops of savlon
100%-10:0 - zero drop of water and ten drops of savlon
0% - 0:10 -ten drop of water and zero drops if savlon
10%- 1:9- nine drop of water and one drop of savlon
50%- 5:5- five drop of water and five drops of savlon
100%-10:0 - zero drop of water and ten drops of savlon
2. The dependent variable that I will be measuring is.
The dependent variable that we are measuring is the clear rings around the savlon area to see how far the dettol killed. We are going to measure the rings in mm by using a mm ruler across the rings to measure the diameter.
3. The controlled variables that I will be keeping the same are… and how?. The thing we kept same was the type of bacteria used. we didn't change the concentration of the type of bacteria (yoghurt).
FAIR TEST:
Which variable will have to be measured or observed in order to get some data or information from the investigation? (This is the dependent variable)
FAIR TEST:
Which variable will have to be measured or observed in order to get some data or information from the investigation? (This is the dependent variable)
The variable that we have measured is the circle rings around the savlon coated paper.The rings that are cleared of all bacteria are the variable we are measuring.
How will the dependent variable be measured or observed?
The dependent variable is the circle salvon rings that will be measured in mm. I will be using a ruler to measure across the circle to measure the diameter.
| Other variables that need to be controlled to make your results more accurate. | |
Other variables
|
Describe how this variable will be controlled or kept the same.
|
Bacteria (yoghurt) | The bacteria will have to be controlled by evenly pouring in in the agar plate carefully to making sure that the same amount of bacteria is contained on each. The bacteria will also have to be the same type of bacteria so that the growth time is the same. |
sterilisation | We dipped the tweezers in the ethanol to sterilise it, so we don't disinfect the savlon. By doing it, it will lessen the probability of disinfecting the savlon and the yoghurt. It also kills any bacteria on the tweezers. |
pipette | The pipette will be controlled by cleaning the pipette each time we do a different concentration to make sure the that the concentration clean and acuate to the measurement. we will control this by cleaning the pipette each time after a different concentration added. |
| How will you ensure that your results are reliable? My result was reliable because we used three agar plates and they gave use similar result one each of our agar plates. This helps us determine the average size of the circle disinfectant ring in case of any mistake in our concentration. | |
| Notes from your trials. We note that three agar plates helped us determine the correct result for the experiment in case of any mistake or problem while doing the experiment or after eg contamination. | |
EQUIPMENT:
-Agar plate -bunsen burner -pen -cotton bud -yoghurt -savlon -stopping tile
-pipette -hole punch -filter paper -tweezers -ethanol -tape -water - beakers
METHOD:
1.label the agar plate into four sections
2.smear the yoghurt evenly with a cotton bud around the plate.
3. fill one-half a beaker of water and one-half a small beaker with savlon
3. fill one-half a beaker of water and one-half a small beaker with savlon
4.dilute the savlon in a spotting tile
0% - 0:10 -(ten drop of water and zero drops if savlon
10%- 1:9- (nine drop of water and one drop of savlon)
50%- 5:5-(five drops of water and five drops of savlon)
100%-10:0 - (zero drop of water and ten drops of savlon)
10%- 1:9- (nine drop of water and one drop of savlon)
50%- 5:5-(five drops of water and five drops of savlon)
100%-10:0 - (zero drop of water and ten drops of savlon)
5. hole punch the filter paper four times
6. drip the tweezers in ethanol and wave throw flame.
7. Use the tweezers to pick up one hole punched circle then drop in the 100% concentration
8.then pick up it up and put onto the agar plate
9. Repeat the ethanol in the flame process, use the tweezers to pick up the next whole punched circles in the concentration and repeat the process with all four circles
10. When done tape the end of the agar plate and leave overnight.
MEASUREMENTS/ RESULT
ANALYSIS:
CONCLUSION:
MY DATA SHOWED:
My data showed that my prediction that the savlon will leave a circle to where the bacteria have been killed. I predict this because the savlon in a disinfectant that should kill bacteria in the affected area. After analysing the shown graph my prediction is proven right because of the higher concentration the large the ring around the savlon paper. and the smaller concentration had less of a ring around the paper.
I CONCLUDE......
I conclude that the larger that concentration of savlon or disinfectant the large the circle ring is around the disinfection paper. cause a clear circle to appear around the filter paper.
DISCUSSION AND EVALUATION:
When we were analyzing the data shown and doing the experiment I kept asking my self-questions that I found very strange.
These are some of these questions....
- what is disinfectant?
- why does salvon kill bacteria?
- why do bacteria grow in colonies?
- Bacterial Colony Morphology?
does salvon kill bacteria? Salvon kills bacteria because it is a disinfectant. Salvon works to kill bacteria by using the two antiseptics that salvon has called cetrimide and chlorhexidine gluconate. 3. Why do bacteria grow in colines? I was unable to find out why bacteria grows in colines but I learned about Bacterial Colony Morphology that is the differences that each coline shows from different types of bacteria and how to identify the type of bacteria strain. 4. what is in salvon that kills bacteria and helps wounds? Savlon has the ingredients of Cetrimide-This antimicrobial kills microbes by weakening their membranes and entering the cells. Chlorhexidine gluconate-This is a very powerful antiviral, antibacterial and antiseptic. Cetostearyl alcohol-An alcohol made by heating coconut oil with sodium hydroxide.Liquid paraffin-Distilled from crude oil, this emollient is used in hydraulic fluids, baby oils.Methylhydroxy-benzoate and propylhydroxy-benzoate-These preservatives prevent bacteria and fungi from breeding. Fragrance-It has no medical properties, but it does neutralise the smell of the other ingredients.Purified water-Passed through a filtration membrane, the water is cleared of particles and microbes. These all help what heals and kills bacteria in salvon.
THE STRUCTURE OF BACTERIA.
Bacteria that have to consume and break down complex organic compounds are heterotrophs. This includes species that are found in decaying material as well as those that utilize fermentation or respiration. Bacteria that create their own energy, fueled by light or through chemical reactions, are autotrophs.The savlon breaks through the cell membrane because of the cell membrane therefore when we use savlon they shatter the cell membrane and destroy the balance in the cell. The cell membrane is what keeping things enters and exits the cell.
- Capsule - Some species of bacteria have a third protective covering, a capsule made up of polysaccharides. Capsules play a number of roles, but the most important is to keep the bacterium from drying out and to protect it.
- Cell Envelope - The cell envelope is made up of two to three layers: the interior cytoplasmic membrane, the cell wall, and -- in some species of bacteria -- an outer capsule.
- Cell Wall - Each bacterium is enclosed by a rigid cell wall composed of peptidoglycan, a protein-sugar (polysaccharide) molecule. The wall gives the cell its shape and surrounds the cytoplasmic membrane, protecting it from the environment. It also helps to anchor appendages like the pili and flagella, which originate in the cytoplasm membrane and protrude through the wall to the outside.
- Cytoplasm - The cytoplasm, or protoplasm, of bacterial cells is where the functions for cell growth, metabolism, and replication are carried out. It is a gel-like matrix composed of water, enzymes, nutrients, wastes, and gases and contains cell structures such as ribosomes, a chromosome, and plasmids.
- Cytoplasmic Membrane - A layer of phospholipids and proteins, called the cytoplasmic membrane, encloses the interior of the bacterium, regulating the flow of materials in and out of the cell. This is a structural trait bacteria share with all other living cells; a barrier that allows them to selectively interact with their environment.
- Flagella - Flagella (singular, flagellum) are hairlike structures that provide a means of locomotion for those bacteria that have them.
- Nucleoid - The nucleoid is a region of cytoplasm where the chromosomal DNA is located. It is not a membrane-bound nucleus, but simply an area of the cytoplasm where the strands of DNA are found. Most bacteria have a single, circular chromosome that is responsible for replication, although a few species do have two or more.
- Pili - Many species of bacteria have pili (singular, pilus), small hairlike projections emerging from the outside cell surface. Without pili, many disease-causing bacteria lose their ability to infect because they're unable to attach to host tissue.
- Ribosomes - Ribosomes are microscopic "factories" found in all cells, including bacteria. They translate the genetic code from the molecular language of nucleic acid to that of amino acids—the building blocks of proteins. Proteins are the molecules that perform all the functions of cells and living organisms.
Before binary fission occurs, the cell must copy its genetic material (DNA) and segregate these copies to opposite ends of the cell. Then the many types of proteins that comprise the cell division machinery assemble at the future division site. There are groups of bacteria that use unusual forms or patterns of cell division to reproduce. Some of these bacteria grow to more than twice their starting cell size and then use multiple divisions to produce multiple offspring cells. Some other bacterial lineages reproduce by budding. Still, others form internal offspring that develop within the cytoplasm of a larger mother cell. The following are a few examples of some of these unusual forms of bacterial reproduction.
GROWTH: BATCH CULTURE
Bacterial growth is the asexual reproduction into two daughter cells, in a process called binary fission. Providing no mutational event occurs, the resulting daughter cells are genetically identical to the original cell. If the number surviving exceeds unity on average, the bacterial population undergoes exponential growth. batch culture can be modelled with four different phases: lag phase, log phase or exponential phase, stationary phase, and death phase
Phase 1: lag phase-Bacteria initially placed in the culture begin to take nutrients, synthesize their RNA and their proteins. They are not ready to replicate yet.
Phase 2: Exponential or lag phase- Bacteria replicate quickly, using the readily available nutrients in the broth.
Phase 3: Stationary phase- Depletion of essential nutrients causes the bacterial growth rate and death rate to be equal during this phase.
Phase 4: Death phase- Bacteria as the nutrients are no longer readily available.
The process of binary fission, and a diagram of the 4 phases of bacteria growth. Bacteria is living thing, we know this because of the anagram MRS GREN. MRS GREN stands for:
Movement - all living things move
Respiration - Getting energy from food
Sensitivity - detecting changes in the surrounding
Growth - all living things grow
Reproduction - making more living things of the same type
Excretion - getting rid of waste
Nutrition - taking in and using food
Phase 3: Stationary phase- Depletion of essential nutrients causes the bacterial growth rate and death rate to be equal during this phase.
Phase 4: Death phase- Bacteria as the nutrients are no longer readily available.
The process of binary fission, and a diagram of the 4 phases of bacteria growth. Bacteria is living thing, we know this because of the anagram MRS GREN. MRS GREN stands for:
Movement - all living things move
Respiration - Getting energy from food
Sensitivity - detecting changes in the surrounding
Growth - all living things grow
Reproduction - making more living things of the same type
Excretion - getting rid of waste
Nutrition - taking in and using food
EVALUATION:
This experiment was reliable because we made accurate measurements and ratios that were
appropriate for these types of experiment. The experiment was reliable cause the graph shows no anomalies resulting from a measurement. In the beginning, we have to redo the start the diluting of the savlon again after we accidentally added too much water to ration so to make it accurate and reliable we restarted the dilutions again avoided doing that again to the new samples. The only major anomalies in the data that are obvious are the high diameter on agar plate three because the 50% is large that the 100%. The only major problem that we had doing this experiment we the dilution so next time we could be more careful not to waste resources that could be useful for other classes.
Bibliography
No comments:
Post a Comment
Note: only a member of this blog may post a comment.