Saturated chains pack tightly, resulting in a more rigid, less fluid membrane.
The phosphate group is negatively charged and highly attracted to water.
Carrier proteins bind specific molecules and shift conformation to move them across the membrane.
It is passive (no ATP) but uses a protein facilitator.
Many peripheral proteins are connected to the cytoskeleton on the cytoplasmic side of the membrane.
Plants typically have higher levels of unsaturated fats to adapt to ambient temperatures.
Singer and Nicolson proposed the Fluid Mosaic Model in 1972.
Most cytoskeletal anchors are peripheral proteins attached to the cytoplasmic surface.
The fatty acid tails create a hydrophobic region that prevents passage of polar substances.
The Robertson model (Unit Membrane) described a fixed, trilaminar structural arrangement.
Because facilitated diffusion uses a limited number of proteins, the rate can reach a maximum (saturation).
While proteins may contribute more by mass, phospholipids are the most numerous molecules.
Mosaic implies a diverse pattern of different components (proteins, lipids, carbs) packed together.
Small, non-polar molecules move easily through the non-polar lipid bilayer.
Plasmalemma is essentially the plasma membrane of a cell.
Membrane proteins can act as enzymes to catalyze reactions at the membrane surface.
Selective permeability ensures only specific molecules can pass, keeping internal homeostasis.
Glycoproteins and glycolipids on the surface form the glycocalyx, involved in cell adhesion.
The Na+/K+ pump moves ions against their gradients using ATP, defining it as active transport.
nmdcat.online
10980 MCQs
NMDCAT.ONLINE
1 MCQ
GULABsb
1 MCQ
