Chapter 12
Membrane Structure and Components
A cell's plasma membrane demarcates the cell's borders and determines the nature of its interaction with the environment. Cells exclude…
Membrane fluidity is explained by the fluid mosaic model of the cell membrane, which describes the plasma membrane structure as a mosaic of…
Scientists identified the plasma membrane in the 1890s and its principal chemical components (lipids and proteins) by 1915. The model for plasma…
Lipids are an essential component of all biological membranes. The average lipid content in mammalian membranes is 50%, though it can be as low as…
Biological membranes show uneven distribution of different types of lipids in the inner and outer layers, resulting in transverse asymmetric…
Enzymes like flippase, floppase, and scramblase transfer phospholipids from one layer to another in the membrane, thereby affecting membrane…
The plasma membrane is a dynamic barrier composed of lipids, proteins, and carbohydrates. It is the epicenter of many cellular processes required for…
Plasma membranes have integral transmembrane proteins involved in facilitated transport. These proteins are collectively referred to as transport…
In the plasma membrane, the lipids forming the bilayer can also act as an anchor to tether proteins to the membrane. The three main types of lipid…
Integral membrane proteins are tightly associated with the cell membrane and play a crucial role in cell communication, signaling, adhesion, and…
In multi-pass transmembrane proteins, the polypeptide chain crosses the membrane more than once. The transmembrane polypeptide chain either forms an…
Detergents are used to purify the integral proteins of the membrane. The hydrophobic portion of the detergent can replace membrane phospholipids…
Proteins show rotational as well as lateral diffusion across the membrane. The lateral diffusion of proteins was confirmed through the cell fusion…
The membrane domains concentrate specific lipids and proteins at one place within the membrane, which helps in cell signaling, adhesion, and other…
Different physical properties of lipids and proteins allow them to localize and form distinct islands or domains in the membrane. Some membrane…
The living membranes are flexible due to their fluid mosaic nature; however, their bending into different shapes is an active process regulated by…
Robust in vitro investigations of the structure and function of integral membrane proteins has been a challenge due to the complexities of the plasma…
Several methods have been developed to functionally characterize novel membrane transporters. Polyamines are ubiquitous in all organisms, but…
Lipid bilayers form the main matrix of cell membranes and are the primary platform for nutrient exchange, protein-membrane interactions, and…
