When a person eats a meal rich in carbohydrates, their pancreatic cells begin to produce and secrete the protein insulin, which helps the body process sugar. When the blood sugar returns to normal, the insulin production stops. What is the benefit of this ability to turn gene expression on and off in response to a signal?

In the lac operon, when glucose levels are low, a protein called the catabolite activator protein (CAP) binds to the promoter region and helps RNA polymerase bind more efficiently, thereby increasing the rate of transcription. What type of control is this?

A friend tells you she thinks genetically modified organisms are harmful to the environment, too dangerous to use, and that she avoids them. How might you respond to her comments, and what factual information could you share that might help her understand them better and perhaps worry less? How are GMOs created and used, and how does this compare with traditional breeding approaches? Please explain briefly but clearly in a full paragraph (minimum 4-5 sentences).

A scientist is studying a patient with a rare disease. She analyzes the patient’s entire DNA sequence to look for genetic mutations that might be causing the illness. Another scientist is studying all the proteins expressed in the patient’s liver cells at a specific time to understand how the disease is affecting cell function. What are the names of these two fields of study, respectively?

While mRNA vaccines have numerous benefits, they also present unique challenges. Which of the following is a significant challenge associated with the development and storage of the original COVID mRNA vaccines?

The pain reliever ibuprofen is sold as a racemic mixture of two different forms, a R-form and an S-form. The R-form is therapeutically inactive, while the S-form provides the pain relief. What is the correct term for two molecules that are non-superimposable mirror images of each other?

A scientist is using a bacterium to produce a human protein. To do this, they create a version of the human gene from mRNA that has the introns removed. Why is it important to remove the introns from the gene before inserting it into the bacterium?

A species of bacteria  in a lab grows on a nutrient agar containing glucose. The bacteria have genes for metabolizing other sugars, such as lactose and sucrose, but they are not being expressed. What is the reason for this?

In a forensics lab, a small DNA sample is obtained from a crime scene and amplified. To identify the suspect, the amplified DNA is cut into fragments of different sizes and separated based on their length. Which technique is used to separate the fragments?

Consider what you have learned in Unit 4 of this class. Please pick a single topic, e.g., a single learning objective we have covered. This might be something you found especially interesting, something you initially struggled with but then learned well, something you are especially confident of and perhaps wished was covered more thoroughly on this test, or anything else you want from this content, except please do not pick one of the topics already discussed in the essay questions (i.e., do not re-discuss the essay questions you already answered). For this topic: Identify the topic Explain the topic and why it is important Write a single multiple choice question addressing this topic Your answer should be a paragraph of at least 4-5 sentences. Please do not just list out names of multiple topics, or just tell me that you found a topic to be really interesting. You may tell me you found this topic especially interesting, but you must demonstrate that you learned about and understand this topic by explaining it clearly. Note that there is not a single answer to this question, this is your chance to demonstrate good knowledge of any topic of your choosing from your work in this unit!