Lab Final Flashcards
What must be included in a lab notebook?
Title Date Purpose Methods Data Conclusions
C. elegan control
heat killed S. Marcescens
cannot infect C. elegans, but smells good to them
C. elegans experimental plate
Serratia on one side
E. coli on the other
What should be labeled on a plate for c. elegans?
Date Group name Type of plate (evolution or control) Lab section Lab room number Passage number
Parts of a scientific abstract
Introduction
Materials and Methods
Findings/results
Discussion
Components of the introduction of a scientific abstract
Context, knowledge gap, and objectives
Where does the microbiome come from?
Fetus is probably sterile
Bacteria is acquired at birth, changes as the human develops/changes
Bacterial composition is highly variable
What is the microbiome thought to be determined by?
Diet
Genetics/immune system
environment
How can the microbiome negatively affect a person’s health?
certain species have been identified in gastrointensional distress, weight gain, and neurological diseases
Is most bacteria in the microbiome beneficial?
yes
helps with food digestion, wound healing, gut barrier function
Why is the bean beetle a good model organism?
easy to maintain
short life cycle (about 1 month)
tiny, but not too small
eats one bean that larvae was on and never eats again…can completely control diet
Broad and specific research questions of bean beetle project
Broad: How does diet affect the microbiome?
General: Do beetles raised on different bean types have different microbiomes?
PEA plate
selectively cultivates Gram positive microbes
P = Positive
EMB plate
selectively cultivates Gram negative microbes
Cellulose plates
contains indicator that will show color change around microbes that can digest cellulose
Gram negative bacteria
have an outer membrane ontop of their peptidoglycan cell wall
Why do we sterilize the bean beetles?
sterilize their outside, so we only culture internal bacteria
Why do we plate both diluted and undiluted beetle microbiomes?
Some beetles have tons of microbes while others have much less
What should be labeled on the bean beetle plates?
Group name date lab section lab room beetle type beetle # dilution type of plate
What are the 2 ways that scientists think about diversity?
- Species richness
2. Species evenness
Species richness
total number of species present
Species evenness
the numbers of each species are pretty even
Inverse Simpson’s Index
1/ (# of species A /total)^2 + (# of species B/total)^2…
What plates do we use for diversity measures?
EMB and PEA plates
since they show gram-negative vs. gram-positive bacteria