Which is/are not transport protein (s):
**Core Concept**
Transport proteins, also known as carrier proteins, are a class of proteins that facilitate the movement of molecules across cell membranes. They play a crucial role in maintaining cellular homeostasis by regulating the concentration of ions, nutrients, and waste products within the cell.
**Why the Correct Answer is Right**
The correct answer includes proteins that do not facilitate the transport of molecules across cell membranes. **Option C**, Glycoproteins, are a type of protein that contains carbohydrate moieties and are involved in various cellular processes, but they are not primarily transport proteins. **Option D**, Enzymes, are proteins that catalyze biochemical reactions, but they do not transport molecules across cell membranes.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is missing, but if it were a transport protein, it would be incorrect because it would be a correct example of a transport protein, not an incorrect one.
* **Option B:** This option is missing, but if it were a transport protein, it would be incorrect because it would be a correct example of a transport protein, not an incorrect one.
**Clinical Pearl / High-Yield Fact**
It's essential to remember that transport proteins can be classified into several types, including channel proteins, carrier proteins, and facilitated diffusion proteins, each with distinct mechanisms of action.
**Correct Answer:** C. Glycoproteins, D. Enzymes.