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extrinsic protein
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Detailed diagram of a plasma membrane's lipid bilayer showing two layers of phospholipid molecules with hydrophilic heads facing outward and hydrophobic tails inward, embedded cholesterol, integral (intrinsic) proteins spanning the membrane, peripheral (extrinsic) proteins attached to the surface, and sugar side chains extending from the outer face.
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extrinsic protein

biology
Also known as: peripheral protein
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Detailed diagram of a plasma membrane's lipid bilayer showing two layers of phospholipid molecules with hydrophilic heads facing outward and hydrophobic tails inward, embedded cholesterol, integral (intrinsic) proteins spanning the membrane, peripheral (extrinsic) proteins attached to the surface, and sugar side chains extending from the outer face.
Molecular view of the cell membrane Intrinsic proteins penetrate and bind tightly to the lipid bilayer, which is made up largely of phospholipids and cholesterol and which typically is between 4 and 10 nanometers (nm; 1 nm = 10−9 metre) in thickness. Extrinsic proteins are loosely bound to the hydrophilic (polar) surfaces, which face the watery medium both inside and outside the cell. Some intrinsic proteins present sugar side chains on the cell's outer surface.

In biology, extrinsic proteins are loosely attached to the surface of the cell membrane's phospholipid bilayer. They can be connected by ionic bonds or calcium bridges. These proteins can also associate with intrinsic proteins, which are embedded within the membrane itself. Extrinsic proteins are not an integral part of the membrane structure, unlike intrinsic proteins which play roles in transport systems like channels and pumps. The term "extrinsic" generally means external or not belonging to the essential nature of something.123

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3 Britannica Sources
  1. cell membrane: Top Questions
  2. cell - Membrane proteins
  3. extrinsic

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