Which is NOT a function of membranes?
Separation of incompatible processes
Creation of concentration gradients
Packaging for transport
Digestion of debris
Which statements about the plasma membrane are CORRECT?
It is a fluid phospholipid bilayer with proteins and other lipids incorporated into it.
It is permeable to hydrophobic molecules like steroid hormones.
It restricts entry of hydrophilic and ionic (charged) molecules/
It is always saturated.
Cholesterol acts as a fluidity buffer for the plasma membrane as it makes the phospholipid layer more viscous, but also lowers its solidifying point,
Proteins are unspecific to cell type.
There are two types of transport in regards to energy transfer: passive and active. Passive is from ❌ concentration, "❌" a gradient. Active is from ❌ concentration, "❌" a gradient.
Facilitated diffusion is a form of ❌ transport where molecules are too large to diffuse through a membrane on their own. Facilitated diffusion involves ❌. Channels can be "leak" channels where molecules can ❌ move, or they can be gated. Voltage-gated channels respond to changes in ❌ whereas ligand-gated channels respond to ❌.
Active transport utilises ❌ that act as pumps which use ❌ to move molecules ❌ a concentration gradient. This is important for maintaining ❌ of ions, and can be direct or indirect. A classic example is the ❌ pump.
Which of the following is not a function of proteins?
Signal transduction
Cell recognition
Linking of membranes to the cytoskeleton or ECM
Linking of cells
Linking of organelles