Hydrophobic and hydrophilic interactions

Question 1

How do R at the surface of a protein determine its location within a cell?

Answer 1

Hydrophilic R groups will predominate at the surface of a soluble protein found in the cytoplasm. In these proteins, hydrophobic R groups may cluster at the center to from a globular structure.

Question 2

Describe the fluid mosaic model

Answer 2

Regions of hydrophobic R groups allow strong hydrophobic interactions that hold integral proteins
within the phospholipid bilayer.

Question 3

Describe integral proteins

Answer 3

Integral proteins penetrate the hydrophobic interior of the phospholipid bilayer. Some integral proteins are transmembrane, for example channels, transporters and many receptors.

Question 4

Describe peripheral proteins

Answer 4

Peripheral proteins are not embedded in the phospholipid bilayer, instead they form weak bonds to the surface of the membrane. Peripheral proteins have fewer hydrophobic R groups interacting with the phospholipids.