Describe the gene and protein defects in phenylketonuria (PKU). How are these defects connected to disease symptoms?

Which of the following describes the 3D structure of multiple polypeptide chains in a single protein?

Which of the following describes the local structures formed in a single polypeptide chain?

Some proteins are composed of two or more polypeptides. Suppose the DNA template strand sequence 3′-TACGTAGGCTAACGGAGTAAGCTAACT-5′ produces a polypeptide that joins in pairs to form a functional protein.

What term is used to identify a functional protein like this one formed when two identical polypeptides join together?