Question

multiple choice question
which type of transporter is best described as an integral membrane protein with cytoplasmic atp - binding domains?
abc transporter
carrier protein
ion channel
porin

Explanation:

To solve this, we analyze each option:

• ABC transporter: ABC (ATP - Binding Cassette) transporters are integral membrane proteins that have cytoplasmic ATP - binding domains. They use ATP hydrolysis to transport substances across membranes.
• Carrier protein: Carrier proteins can transport molecules but not all carrier proteins have cytoplasmic ATP - binding domains (some use other energy sources or are passive).
• Ion channel: Ion channels are usually involved in passive transport of ions and do not have ATP - binding domains for active transport in the way described.
• Porin: Porins are usually beta - barrel proteins that form channels for small molecules and do not have ATP - binding domains.

So the ABC transporter matches the description.

Answer:

A. ABC transporter