LSAMP
S.T.E.M. Summer Institute
Valencia College
West Campus
How to Write
A Basic College Laboratory Report
(Lab report requirements vary slightly from professor to professor)
Title Page
Your lab report needs a title, that is typically 10-15
words in length, that gives a brief explanation about
the content of your experiment.
Your name as well as the date, the course and your
instructor’s name should also go on this page.
Lab reports are not an exercise in creative writing;
you need to be concise and specific!
INTRODUCTION
The introduction is where you give some
background information about the topic that
you are researching and explain the reason you
are performing the experiment. Your hypothesis
and the design of your experiment can be
discussed here.
Materials and Methods
In a paragraph or a list, write exactly how you
performed the experiment, step-by-step. As with all
parts of your lab report, you need to use complete
sentences and the report must be in your own words.
Include precise measurements (and units of
measurement) and the proper names of all lab
equipment used to perform the experiment.
When you are finished, this part of your report
should be able to be used by other scientists to
exactly replicate your experiment.
RESULTS
In this part of your lab report, you should put
your observations and any data gathered during
your experiment. Graphs, tables, charts and
drawings can be included here.
Conclusions
In this part of your lab report, you want to
analyze your data, discuss the findings of your
experiment and come to some conclusion that
explains how the experiment did or did not
support your original hypothesis.
Tips to use when writing a science lab
report:
1) Make sure you proofread your work before submitting it for a grade;
you must use proper grammar and spelling.
2) Your professor may want you to list any references you used when
writing your report; you will need to use the APA (American
Psychological Assoc.), not the MLA (Modern Language Assoc.), citation
style to cite references.
3) Scientists use the metric system; depending on the field you choose
to explore, you should be able to use both the metric and English
systems of measurement and convert units between the two systems.
4) You will need to correctly write any scientific names of organisms
used in any science experiment.
5) Scientific reports are written in the third person, not the first person
(do not say I or we).
Be careful when using pronouns (they or it).
6) Do NOT plagiarize from your lab partners or references!!
Variations to this basic lab
reporting style exist from professor
to professor, so be sure to follow
the directions given to you by your
professor.
Being able to express yourself clearly
when communicating with colleagues
is essential in science. Whether it is
verbal, written or electronic, you have
to be able to express your ideas well.
Scientists need to be critical when looking at the work
of their colleagues. The only way that science
progresses is if your experiments can be replicated
and substantiated by others. That is why you need to
be very clear in your communications with your
colleagues.
Genetics and Genetic Engineering
Genetics is the study of how traits are passed from one
generation of organism to the next;
it’s the study of heredity.
The shape of the DNA molecule is a twisted
ladder shape called a double helix.
The shape of the molecule was discovered in 1953 by
Watson and Crick.
In 1953, James Watson and Francis Crick display their model of
what DNA looks like.
Rosalind Franklin studied DNA by taking X-rays of DNA crystals. Her
findings were useful in helping Watson and Crick discover the shape of
DNA, yet she did not win a Nobel prize? Why?
Rosalind Franklin
X-ray crystallography image
All bacteria have one chromosome that is made of a single
circular loop of DNA (bacterial cells have no nucleus).
Some bacteria have extra small loops of DNA called plasmids
which carry special genes.
Your cells have paired chromosomes which are
linear molecules of DNA that exist in each of
your cell nuclei.
Both chromosomes and genes are made of DNA. Each entire piece of DNA is
called a chromosome. On a chromosome, there are regions of DNA which
code to make RNA which are called genes.
This is a picture of all the chromosomes from one person, called
a karyotype. Humans have 46 chromosomes on which, some
estimate, there are over 20,000 genes.
Human Sex Chromosomes
What is the relationship between DNA, chromosomes and
genes?
- Each individual entire piece of DNA is called a chromosome.
- In a chromosome, there are smaller fragments of DNA that used in the
production of some characteristic), these DNA fragments within a
chromosome are called GENES.
Are there more chromosomes or genes in a cell?
Each gene contains a code that ultimately results in the
production of a specific protein.
The proteins produced by the codes of your genes makes you
you and not your neighbor or a dog or a rose or E. coli, which
all have their own codes in their genes.
Your genes are the codes to make
all of the proteins of your body.
Can you name some of the parts of your body that are
made of protein?
YOU ARE A BIG BAG of PROTEINS!!
Your hair, skin and nails are all made of keratin protein.
Pigments are proteins, so your hair, eye and skin color are due
to proteins.
Muscles are made of actin and myosin proteins.
Cartilage is made of elastin and collagen protein.
Your red blood cells carry oxygen by using hemoglobin
protein.
Your cell membranes contain proteins.
Enzymes, which control the chemical reactions of your body,
like digestion and metabolism, are proteins.
Your immune system (antibodies) depends upon proteins.
Many of your hormones (insulin) are proteins.
Today’s genetic engineering
experiment will involve trying to
put a bacterial plasmid, which has
a green fluorescent protein gene
from a jellyfish inserted into the
plasmid, into E. coli bacteria.
Where do you commonly find E.
coli bacteria?
E. coli under the microscope
E. coli grown on an agar plate.
TRANSFORMATION = the transfer of
small DNA fragments into living
bacterial cells
Let’s see if you can genetically
engineer E. coli to become
antibiotic resistant and glow
green under U.V. light.
Bioart
Before we begin genetically
engineering bacteria, we will need
to learn about lab safety, and
wear…
protective lab outfits.
BENEFITS GAINED THROUGH GENETIC ENGINEERING RESEARCH
The goal of the Human Genome Project was to determine the
nucleotide sequence of the entire human genome; that goal was
accomplished in 2003.
Medical Applications
- genetic engineering of bacteria has allowed for the design of safer,
more effective vaccines (HepB, HiB) (Experimental malaria
and HIV drugs are being tested)
- genetic engineering of bacteria has allowed for the large scale
production of many new and often scarce pharmaceutical
products such as insulin, interferon, hormones, vitamin B12,
antibiotics, artificial blood, immune treatment drugs and
enzymes
- the ultimate goal in genetic engineering is to be able to cure and
prevent human genetic disorders caused by single defective
genes
Humulin is one of many pharmaceutical products made using
genetically engineered bacteria. You will get to genetically engineer
bacteria in our lab and see how easy it is to do.
Agricultural Applications
-TRANSGENIC plants and animals (those containing genes from different
species) are being designed to improve food quality and productivity
(Genetically modified organisms or GMO’s can be controversial,
particularly when they are intended to be eaten; some groups have
called them FRANKENFOODS)
- Transgenic animals are produced by microinjection of genes into fertilized
eggs, milk from pigs, sheep, rabbits and cows are used to make
products needed to treat patients with hemophilia, emphysema,
septicemia, some cancers, heart attack and stroke, burns and more
- Transgenic plants are produced with a “gene gun” which “shoots” plasmids
into plant cell cultures to make plants resistant to chemicals, drought
and extreme temperatures and to make them more nutritious or
able to make their own insecticides and fertilizers
The gene gun shoots genes
into plant tissue.
Glow in the dark tobacco,
genetically engineered with a
gene from a firefly that makes
the enzyme luciferase.
Transgenic crops can be made to produce their own insecticides (as
seen here) and fertilizers. Genes can also be introduced into plants to
allow the plants to grow in environmental extremes, in drought and in
the presence of herbicides. Genes can also be added to increase
nutrient levels (like B vitamins in rice) in plants.
Animal cells can be
microinjected with genes.
A transgenic mouse genetically
engineered with the gene for
human ear production.
These transgenic goats will
make human antithrombin in
their milk.
This transgenic goat can
produce spider silk in it’s milk.
Genetically Modified Organisms (GMO’s)
Genes can be inserted into animals to make them glow in the dark.
Transgenic maize in Kenya
Transgenic mice are used to
research animal models of
human disease
When will they genetically engineer
humans?
Gene therapy in humans
SAFETY AND ETHICS
Genetic engineering is regulated in the U.S. by the:
NIH (National Institutes of Health)
USDA (United States Dept. of Agriculture)
EPA (Environmental Protection Agency)