What is a protein that transports ions across the plasma membrane without requiring energy or changing shape?

The protein you are referring to is called a channel protein. Channel proteins are a type of integral membrane protein that form specialized channels or pores in the plasma membrane, allowing the passage of ions, such as sodium (Na+), potassium (K+), and chloride (Cl-), without requiring energy or changing their own shape.

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1. Start by understanding the topic: In this case, you need to know about the different types of proteins involved in ion transport across the plasma membrane.

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3. Use appropriate keywords: Some relevant keywords to use in your search could include "protein," "ion transport," "plasma membrane," and "energy-independent."

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6. Read the relevant information: Once you have found a suitable source, read the content to identify the specific protein that transports ions across the plasma membrane without requiring energy or changing shape.

Remember, as an AI bot, I am providing general guidance on how to conduct research to find the answer. It's always important to verify information from trusted and reputable sources to ensure accuracy.