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What is the ratio of expected phenotypes in the offspring produced by the cross Aa × Aa? Assume complete dominance for the trait. 

Background Sulfa drugs are a type of antibiotic that interfere with how bacteria make the building blocks of their DNA. These Sulfa antibiotics work by targeting a bacterial enzyme that is essential for the bacteria’s survival. These antibiotics mimic a normal substrate the bacteria needs; they bind to the enzyme’s active site and block the real substrate from entering. As a result, the bacteria cannot produce nucleotides, which are necessary for their reproduction and survival. Question Identify the name of this ‘bacteria-building blocking’ process and describe the specific mechanism by which these drugs prevent bacterial growth. Then, explain how these antibiotic drugs function at the molecular level.

List all possible gametes of an organism that is AaBb.  HINT:  FOIL

A cell with 10 chromosomes undergoes mitosis and complete cell division. How many daughter cells are produced, and what number of chromosomes do they have? 

If the DNA of a certain organism has guanine as 30% of its bases, then what percentage of its bases are adenine? 

Patau Syndrome is a chromosomal condition known as Trisomy 13 and is caused by a translocation. Surviving children with this condition have several developmental disabilities, polydactyly, and multiple organ defects among other issues. Explain what Trisomy 13 means, what a translocation is, and when it might occur during meiosis.

In mink, black is completely dominant to brown.  The allele designated B causes the black color, and b when homozygous, results in brown.  What would be the expected phenotypes in the offspring of a cross of two brown minks? 

If a parent cell has 16 chromosomes, how many sister chromatids will be present after duplication of the chromosomes? 

Scenario A shipwrecked man drinks salt water in an attempt to quench his thirst. The salt increases the solute concentration in his blood plasma, affecting water movement between his red blood cells and plasma due to osmosis. Question Fill in the two blanks to best describe how the tonicity in his bloodstream will change. The blood plasma will become ________ relative to his red blood cells. The red blood cells will be ________ relative to the blood plasma.

Question Which of the following is an example of a NON-scientific study?