A relative of a friend of yours had a spinal cord injury after a bad car accident. The medical team has decided that this patient is a good candidate for a clinical trial using stem cell therapy. Your friend has not had a biology course since high school, so you […]

Suppose that an enzyme uses a catalytic mechanism in which a functional group on the enzyme has to accept a proton from the intermediate formed in the first chemical step. The pKa of that basic functional group on the enzyme is 8.0, and is the only pKa apparent on a […]

1. List at least three functions of our skeletal system. 2. What are two things that our skeletal system stores? 3. What type of bone cells break down bone? What type of event would cause them to break down bone? 4. What type of bone cells form bone tissue? What […]

You’re trying to PCR amplify a gene, but your gel shows that there are two bands instead of only one like you expected. You know for certain that there no homologous genes in the genome from which you’re amplifying, so you assume that the issue must be coming from your […]