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Compared to a normal body cell, a normal egg cell contains*
The diagram below represents a microscopic structure observed during mitosis.
The region indicated by letter A is known as*
The diagram below represents a cell.
Which letter indicates the specific structure where most hereditary mutations occur?*
Traits are passed from parents to offspring. These traits are determined by*
Mutations are most directly caused by changes in the*
Which sequence correctly represents the arrangement of structures containing genetic material, from the largest to the smallest size?*
Which statement is correct concerning hereditary information?*
Base your answers to questions 8 on the diagram below and on your knowledge of biology.
The original gene for the production of a human hormone was most likely removed from a*
A weightlifter has spent years building his muscular strength. His newborn daughter has normal strength for a baby. Which statement best explains this situation?*
In a DNA sample, 15% of the bases are thymine (T). What percentage of the bases in this sample are adenine (A)?*
The instructions for the genetic traits of an organism are directly determined by the*
Base your answers to questions 12 on the DNA base sequence below and on your knowledge of biology.
AAC–GCC–GTC–CGC–TAG
Identify the mRNA codons that would be produced using this DNA as a template. [1]
DNA base sequence: AAC GCC GTC CGC TAG
mRNA codons: _____ _____ _____ _____ _____*
Base your answers to questions 13 on the information below and on your knowledge of biology.
DNA samples were taken from three different species and used to determine the amino acid sequence for a portion of a particular protein. The amino acids were then compared in order to determine which species were most closely related. Some of the information is shown on the table below.
TGA ACU
TGA ACU THR AGA UCU SER
State one specific effect on the protein produced if an mRNA code is changed from AGU to AGA. [1]*
A double-stranded DNA sample was analyzed to establish the percentage of different molecular bases present. The data table below shows the percentage of adenine bases found. Calculate the percentage of each of the three remaining molecular bases, and write the percentages of each in the chart. [1]
*
Base your answer to question 15-18 on the information below and on your knowledge of biology.
Chickens as Drug Factories
Scientists in Scotland have successfully produced five generations of chickens that lay eggs containing certain protein-based drugs. The scientists changed the DNA of the chickens so that two drugs, one used to treat skin cancer and the other used to treat multiple sclerosis, were present in the egg whites. Cows, sheep, and goats have already been altered to produce protein-based drugs in their milk. Chickens are considered good “drug factories” because they are inexpensive to care for, they grow fast, and their chicks inherit the special drug-producing ability.
Explain why scientists altered the DNA of the chickens instead of altering a protein already present in the chickens. In your answer, be sure to:
• identify the technique used to alter the DNA [1]
• state one reason why the scientists altered the DNA of the chickens instead of altering a protein already present in the chickens [1]
• state one advantage of using chickens for this procedure [1]
• state one reason why some people might not support this method of drug production [1]*