Traditional genetic engineering methods like transformation lack the ability to target where genes are inserted into an organism’s genome. In contrast, the CRISPR-Cas9 system can precisely locate the gene in the genome to be edited. What component of the CRISPR-Cas9 system ensures it will only edit the target gene?

The diploid chromosome number of the house fly, Musca domestica, is 12 (2n = 12). After completing meiosis, how many chromosomes would you find in each house fly gamete?

Which phylogeny is best supported by the DNA sequence similarity data in the table below? birds crocodilians lepidosaurs (lizards) turtles mammals birds 100% crocodilians 88% 100% lepidosaurs (lizards) 72% 71% 100% turtles 70% 72% 91% 100% mammals 60% 58% 60% 59% 100% Hint: Compare all of the DNA similarities.  

The “ABO” blood group in humans is characterized by a single gene with three alleles: A, B, and O.  A and B are co-dominant with each other, while O is recessive to both A and B. These allelic interactions give rise to four possible phenotypes: type A, B, O, or AB blood. Given the allelic interactions described above, some phenotypes can result from more than one genotype (e.g., the genotypes AO and AA both result in type A blood). Suppose a woman with type AB blood gives birth. After taking her child home from the hospital, she discovers the child has the following phenotype: type O blood. Given both the mother and child’s phenotypes, which of the following conclusions is correct?

DNA is built of nucleotides. There are four unique nucleotides found in DNA, cytosine (C), guanine (G), adenine (A), and thymine (T). What component of a nucleotide gives its unique characteristics and corresponds to its shortened name?

In 2000, the artist Eduardo Kac unveiled his bio-engineered art piece named “Alba,” a transgenic rabbit created using transformation. Alba’s cells carried a gene derived from jellyfish that produces GFP, a green fluorescent protein. When Alba was illuminated with UV light, she fluoresced a bright lime green color. To create Alba, genetic engineers had to first create a/an recombinant DNA vector that consisted of a jellyfish [coding] gene that produced GFP and a rabbit [regulatory] gene. This vector was then inserted into the genome of the embryo that ultimately developed into Alba.

To make copies of specific DNA sequences in the lab, scientists use polymerase chain reaction (PCR). During PCR, heat is used to “unzip” the two strands that comprise the DNA molecule. PCR mimics DNA replication in some ways, but not in how the two strands are pulled apart. How are the two strands of DNA unzipped during DNA replication in the cell? 

“Splicing” is one way eukaryotic organisms regulate gene expression. What is involved in the process of splicing?

We reviewed multiple definitions of life, including one from the textbook. All of these definitions identified a common set of basic characteristics that must be met for something to be considered alive. Which of the following characteristics is not included in the basic definition of life?

Interactions in gene networks describe…