Transport proteins are specialized proteins that facilitate the movement of substances across cell membranes. They play a crucial role in maintaining cellular function by allowing essential molecules, such as ions, nutrients, and waste products, to enter or exit the cell. These proteins can be classified into two main types: channel proteins, which create openings for specific molecules, and carrier proteins, which bind to substances and change shape to transport them. These proteins are vital for various biological processes, including cell signaling, metabolism, and maintaining homeostasis. Without transport proteins, cells would struggle to obtain necessary resources or remove harmful substances, leading to impaired function and overall health issues.