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 PageYour 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!

INTRODUCTIONThe 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 KenyaTransgenic 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)