A researcher is studying the transport of a novel molecule across a synthetic lipid bilayer. They observe that the molecule moves down its concentration gradient without the need for any membrane proteins or energy input. However, the rate of transport is significantly slower than predicted for simple diffusion. Which of the following BEST explains this observation?
The molecule is very large and its size restricts diffusion through the membrane.
The molecule is charged and is repelled by the hydrophobic core of the bilayer.
The molecule is polar and its passage is hindered by the hydrophobic core of the bilayer.
The molecule is binding to a specific receptor on the membrane surface, slowing its diffusion.
Related Questions
The cell membrane maintains a distinct phospholipid composition between its inner and outer leaflets. Which of the following transport mechanisms is primarily responsible for establishing and maintaining this asymmetry?
Simple diffusion
Facilitated diffusion
Flippases
Ion channels
Structural lipids of cell membrane are
Simple lipid
Chromolipids
Steroid
Phospholipids
Which component of the cell membrane is primarily responsible for its selective permeability?
Glycoproteins
Peripheral proteins
Phospholipid bilayer
Cholesterol
Which of the following is characteristic of phospholipids of plasma membrane?
One non-polar head and two polar tails
One polar head and two non-polar tails
Two non-polar heads and one polar tail
Two polar heads and one non-polar tail
Which of the following is the primary component of the cell membrane?
Carbohydrates
Proteins
Nucleic acids
Phospholipids
Cell adhesion and cell recognition occur due to biochemicals of cell membrane named
Lipids
Proteins
Glycoproteins and glycolipids
Both (a) and (b)
Cell membrane in animals is composed mainly of the molecules of?
phospholipids
carbohydrates
nucleic acids
proteins
Cell membrane in animals is composed mainly of the molecules of?
Lipids
Proteins
1 and 2
Carbohydrates
The fluidity of the cell membrane is primarily influenced by the:
Amount of cholesterol present
Saturation level of fatty acid tails in phospholipids
Concentration of peripheral proteins
Presence of glycoproteins
Most common type of lipids found in plasma membrane is A and they show B__ movement with in the plasma membrane. Choose the most appropriate option to fill A and B.
Phospholipids; Lateral
Glycolipids; Transverse
Cholesterol; Rotational
Steroids; Flip-flop
