Amgen Biotech Experience:

For the second year in a row, Magh Ene College is taking part in the Amgen Biotech Experience in connection with UCD.  As part of this programme, the school receives materials on loan for a two week period to allow students to carry out DNA analysis using equipment normally only available at third level or in industry. Forty schools in the country, mainly in the Dublin area are taking part in this programme this year. Thanks to Ms.Higgins to attended the training day for this initiative.  Over the course of the two week period a range of Science classes from different year groups and subject areas (Biology, Chemistry, Agricultural Science and Junior Cycle Science) had the opportunity to take part in this highlyenjoyable programme.

DNA Gel Electrophoresis

Ms Higgins with a variety of year groups carrying out DNA Gel Electrophoresis

LC Biology - DNA Extraction

Photos from Ms Higgins' LC class where they extracted DNA from onion cells. Make sure you know all steps involved and why you do each step.

Chopping onion: 
Breaks cell walls, releasing cytoplasm.
Adding washing-up liquid:
Breaks down cell membranes, releases nuclear material from cell.
Adding salt: 
Minimise attractive forces between DNA and protein, causes DNA to clump together.
Heating mixture to 60 °C for exactly fifteen mins:
Break down of DNAses enzymes. After 15 mins DNA broken down.
Cooling mixture: 
Slowing down any other enzymes before they destroy DNA.
Blending:
Further destroys cell walls and membranes. Causes release of DNA. Blending > 3s cuts DNA strands.
Adding protease:
Breaks down proteins associated with DNA.
Filtering:
Remove large cellular debris. DNA passes through filter with liquid.
Using cold ethanol:
Forms a layer on top of onion filtrate. Alcohol draws water out of DNA molecule, making it less dense - found between two liquids. DNA insoluble in freezing cold ethanol (soluble in alcohol at room temp)
Testing for DNA:
No method of testing for DNA available for use in school labs 

LC Genetics - Extraction of DNA

Recap of Extraction of DNA from Ms Higgins' 6th Year Biology class

LC Biology - Punnett Squares

LC Biology - Dihybrid Crosses

Another 2 questions for tonight's homework

Question 1

The chestnut coat color of horses is due to a recessive gene, while the dominant
allele results in black. The pacing gait is due to a recessive gene, whereas the
dominant allele results in the trotting gait. Show the types of offspring that could
result from a cross of a black trotter (male), heterozygous for both genes, with a
chestnut pacer (female).

a. Possible genotypes for Black coat: ________ Chestnut coat: _______
b. Possible genotypes for Trotting gait: _________ Pacing gait: _________
c. Male genotype: _____________ Male possible gametes: _______________
d. Female genotype: ___________ Female possible gametes: ______________
e. Draw a punnet square
f. Genotypic Ratio:
g. Phenotypic Ratio:
h. What percentage of the offspring will exhibit both dominant traits? _______
i. What percentage of the offspring will be chestnut trotters? ______
j. What are the chances of having a chestnut horse that paces? __ in __

Question 2
(Remember co-dominace)

In shorthorn cattle, the polled condition is dominant over horned. Also, the
heterozygous condition (Rr) of red coat (R) and white coat (r) is roan, an example
of codominance. (The roan coat contains both red and white fur because neither
allele is dominant over the other). If a homozygous polled, white male is bred to a
horned, red female, what will be the appearance of the F1 generation?


a. Possible genotypes for Pulled condition: ________ Horned: _______
b. Possible genotypes for Red coat: _____ White Coat: _____ Roan Coat: _____
c. Male genotype: _____________ Male possible gametes: _______________
d. Female genotype: ___________ Female possible gametes: ______________
e. Draw a punnet square
f. Genotypic Ratio:
g. Phenotypic Ratio:
h. What percentage of the offspring will exhibit both dominant traits? _______
i. What percentage of the offspring will be roan? ______
j. What are the chances of having a horned, white cow? __ in __
k. If you bred two of the F1 generation, what percentage of the new offspring (F2
generation) will exhibit both dominant traits? _______
l. If you bred two of the F1 generation, what percentage of the new offspring (F2

generation) will be horned and have a roan coat? _______

LC Biology - Dihybrid Cross Problems

In grasshoppers, the body color of brown is dominant over green. Also, having
strong legs is dominant over having weak legs. A heterozygous brown, homozygous
strong-legged male meets a heterozygous brown, homozygous weak legged female.
They produce a number of offspring. Complete the following.

a. Possible genotypes for Brown body color: ________ Green body color: _______
b. Possible genotypes for Strong legs: _________ Weak legs: _________
c. Male genotype: _____________ Male possible gametes: _______________
d. Female genotype: ___________ Female possible gametes: ______________

e.Draw Punnet Square

f. Genotypic Ratio:
g. Phenotypic Ratio:
h. What percentage of the offspring will exhibit both dominant traits? _______
i. What percentage of the offspring will have a brown body and weak legs? ______
j. What are the chances of having a green grasshopper with strong legs? __ in __

LC Biology Experiments - Isolation of DNA

Please view photos from today's experiment on the isolation of DNA from onion cells. The reasons for each step is given below

Chopping onion:
Breaks cell walls, releasing cytoplasm.
Adding washing-up liquid:
Breaks down cell membranes, releases nuclear material from cell.
Adding salt:
Minimise attractive forces between DNA and protein, causes DNA to clump together.
Heating mixture to 60 °C for exactly fifteen mins:
Break down of DNAses enzymes. After 15 mins DNA broken down.
Cooling mixture:
Slowing down any other enzymes before they destroy DNA.
Blending:
Further destroys cell walls and membranes. Causes release of DNA. Blending > 3s cuts DNA strands.
Adding protease:
Breaks down proteins associated with DNA.
Filtering:
Remove large cellular debris. DNA passes through filter with liquid.
Using cold ethanol:
Forms a layer on top of onion filtrate. Alcohol draws water out of DNA molecule, making it less dense - found between two liquids. DNA insoluble in freezing cold ethanol (soluble in alcohol at room temp)
Testing for DNA:
No method of testing for DNA available for use in school labs

LC Biology - DNA Profiling