Culturing of Bacteria found at Hendrickson High School PreAP Biology

Question or Problem Statement Where in Hendrickson High School do we find bacteria that, when given the proper conditions, will grow and flourish?

Background information: Unicellular Prokaryotic Reproduce quickly if conditions are right Most are helpful Recycle wastes, fix N, help digest food, used in food processing Harmful bacteria are called pathogenic Strep, pneumonia, MRSA

Background information cont. Bacteria are living things and therefore need Water, space, food, warmth

Hypothesis: IF we mark our petri dish into quadrants and collect bacteria from 1. (sample location a) 2. (sample location b) 3. (sample location c) 4. (sample location d) THEN……… (use your brain and tell me what you think will be the result)

Materials: Sharpie Agar filled petri dish Sterile Cotton swab Distilled water Parafilm Incubator Ruler Microscope

Experimental Procedure: Wash hands and sanitize your lab surfaces before beginning this lab. Mark your dish into quadrants (on the bottom) with the sharpie. Put your group leader’s name & period on the bottom of the dish. Moisten your swab with distilled water. Do NOT touch the tip of your swab with your fingers. Locate and jot down the locations from where you will pick up your bacteria (this should match your hypothesis statement!!!!

Experimental Procedure cont. Pick up your bacteria using the swab. Clam-shell your dish and streak your plate ON YOUR ASSIGNED QUADRANT. Close the dish immediately When all 4 of you have streaked your plate, tape closed with parafilm. Place in the incubator on the assigned shelf UPSIDE DOWN.

Experimental Procedure cont. Incubate for 24 hours. Remove dish and collect data Qualitative Quantitative Dispose of your dish following your teacher’s directions. Sanitize all lab surfaces Wash hands with antibacterial soap and water.

Safety: Some bacteria may be pathogenic. Sanitize all lab surfaces and wash hands before beginning this lab. Absolutely NO eating or drinking of any kind before during and after this lab. Sanitize all lab surfaces when lab is complete. Dispose of lab materials following directions.

Experimental Data: see, smell, touch, taste, feel, hear, measure, mass, count Make good scientific observations and descriptions Bad example: it looks and smells really gross Good example: the bacteria culture appears slick, is a pale milky yellow color has a strong mal odor similar to bad breath

Analysis & Discussion of Data results: After getting your data you must discuss the implications of that data. What does the data mean? What inferences can we make from the data. What are the possible reasons for this particular data.

Experimental error: Discuss possible mess-ups in lab protocol that may have affected your results. If you did not get the results expected, tell what you believe may be the cause of this. If your data is quantitative you must include a mathematical equation along with your error analysis statement. Difference between observed and expected/expected = X% error.

Conclusion Statements: Your conclusions must be based upon your hypothesis and your data…nothing else. Use the terms supported and refuted According to data…. The data suggests…. Avoid “it”, “that” and “like”