A radioactive isotope decays at a rate proportional to the amount of isotope present. If the concentration of isotope is C (mg l^-I), its rate of decay is:

                                                                    

A solution of the isotope ³²p is used to radioactively label DNA for hybridisation studies. The half-life of ³²p is 14.3 days. According to institutional safety requirements, the solution cannot be discarded until the activity is 1% its present value. How long will this take?____________________

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#Question id: 13092

#SCPH28 | Zoology

To express a yeast gene in E. coli, your task is to design a strategy to insert the yeast gene into the bacterial plasmid. Below is a map of the area of the yeast genome surrounding the gene in which you are interested.

 

The distance between each tick mark placed on the line above is 100 bases in length

Below are the enzymes you can use, with their specific cut sites shown 5’-XXXXXX-3’ 3’-XXXXXX-5’

 

The plasmid is 5,000 bases long and the two farthest restriction enzyme sites are 200 bases apart. The plasmid has an ampicillin resistance gene somewhere on the plasmid distal from the restriction cut sites.

                              

Which two restriction enzymes would you use to design a way to get the insert into the vector if you had to use two enzymes simultaneously?

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#Question id: 10997

#I Life Science/ Life Sciences Group – I-V

A 60-year-old woman has a resting heart rate of 70 beats/min, arterial pressure is 130/85 mm Hg, and body temperature is normal. Her pressure-volume diagram of the left ventricle is shown above.

What is her cardiac output in milliliters per minute?

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#Question id: 9208

#SCPH28 | Zoology

Which of the following threats to biodiversity is targeted at specific species rather than groups of species?

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#Question id: 3652

#SCPH01 Biochemistry

Alkylating agents are electrophilic chemicals which readily add alkyl groups to various positions on nucleic acids. A common example is:

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#Question id: 85

#I Life Science/ Life Sciences Group – I-V

Below is the structure for a cyclic D-monosaccharide. Which is the anomeric carbon atom?