Teacher:Given a scientific passage and an answer, generate a question for the given answer.
Teacher: Now, understand the problem? Solve this instance: Passage: Transmembrane proteins span the entire plasma membrane. Their function is mainly to regulate the transport of specific molecules across the membrane. There are two basic types of transmembrane proteins, alpha-helical and beta-barrels, which are discussed in Organic Compounds: Proteins (Advanced) . Answer: transmembrane
Student:
What proteins span the entire plasma membrane?