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Hi kids. Keep up the good work! I made some comments and corrections for you. Corrections are mostly in red. I hope this helps. – Dr. Knotts. Use full names (first and last) for scientific presentations. Bacterial Growth. Carter, Braeden, Maxwell, and Giles Our group is G5F1 . Our EQs.
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Ms. Moffitt’s Class Hi kids. Keep up the good work! I made some comments and corrections for you. Corrections are mostly in red. I hope this helps. – Dr. Knotts Use full names (first and last) for scientific presentations. Bacterial Growth Carter, Braeden, Maxwell, and Giles Our group is G5F1
Our EQs EQ 1 What does bacteria grow best on? EQ 2 Can bacteria growth be harmful? EQ 3 How is bacteria growth influenced by the concentrations of the nitrousnutrientsin the substrate? EQ 4 Can you use a aseptic culture procedures to measure the population growth of bacteria?
How to cultivate bacteria These things are used to prepare specimens for viewing under the microscope why? You need to get amber bottles, cover slips, 1% crystal violet stain, disposable pipettes, disposable lighter, gram iodine solution, metric ruler, microscope slides, 1% safranin stain, screw cap plastic centrifuge vials,you will also need halobacteriaum, a triple bacteria,a standard transmitted light microscope scale,and a pipettor Name the bacteria you studied: Halobacterium NRC-1 and a triple species mix consisting of Micrococcus luteus, Bacillus subtilis, and Rhodospirillumrubrum These things are use to culture – another name for grow – bacteria.
You used the triple species mix, not Halobacterium, for this experiment. Check me – maybe I’m wrong. Summary of what we did You let the tubes of incubate for one week to allow time for the bacteria to grow. Then you used the tubes to inoculate Petri dishes We added halo bacteria to tubes filled with 10 ml of nutrient broth containing 1% sugar, 64%sugar, 6412% salt, and nutrient brothno added salt or sugar. Then our group added the solutions to plates of nutrient agar using the pippetor (and pipettes).In three weeks the 64%sugar did not have many bacteria colonies. The 6412% salt did not contain many colonies either. The nutrient broth had many bacteria colonies, though it did not have as much bacteria as the 1% sugar. We did the same experiment with a triple mixture of bacteria (Micrococcus luteus, rhodospirillum rubrum, and Bacillus subtilis). You did two other experiments not described in your PowerPoint. Can you say something about them? Experiment 2 compared Halobacterium NRC-1 and the triple species mix using agar in Petri dishes (regular nutrient agar and halobacterium agar containing a large quantity of salt). Experiment 3 involved serial dilutions and comparing growth rates at different temperatures. Italicize the scientific names of organisms such as your bacteria species.
Lesson Review 1 What does bacteria grow best on? 1 In this experiment we learned that bacteria grows best on 1% sugar and nutrient broth but it grows the least 64% sugar and salt. It grows best in warm temperatures such as 16 degrees. 2 Can bacteria be harmful? 2 Yes bacteria can be harmful but not all bacteria can for example frozen yogurt is full of bacteria. It is also frozen alive! 3 How is bacteria growth influenced by the concentrations of the nitrous in the substrate? 3Yes it is affected the bacteria because the need oxygen and Glucose molecules to use in there mitochondria because large nutrient molecules cant just pass through the cell membrane. 4 You can use a aseptic culture to produce bacteria.
Words to know Bacteria Aseptic technique Bacterial suspension Broth cultures Colony counting Nutrient agar Salt sensitive Salt resistant Serial dilutions Substrate Triple mixture