Prepare for NEET with Botany-specific practice questions. Covering all major Botany chapters, this is perfect for your NEET Biology needs.
Lipid rafts are specialized microdomains within the cell membrane. Which of the following statements about their composition and function is INCORRECT?
They are enriched in cholesterol and sphingolipids.
They are involved in signal transduction and membrane trafficking.
They exhibit reduced fluidity compared to the surrounding membrane.
They are primarily composed of unsaturated phospholipids and peripheral membrane proteins.
Which type of membrane protein is MOST likely to be involved in cell-cell recognition and adhesion?
Peripheral membrane proteins
Integral membrane proteins without glycosylation
Glycoproteins
Channel proteins
A researcher is studying facilitated diffusion of a novel solute 'X' across a cell membrane using an artificial lipid bilayer system. They observe that increasing the concentration of X on one side of the membrane increases the rate of transport, but only up to a certain point. Beyond this point, further increases in X concentration do not affect the transport rate. Which of the following BEST explains this observation?
The membrane has reached its maximum permeability for X.
The solute X is being actively transported at higher concentrations.
Saturation of the carrier proteins
The solute X is inhibiting its own transport through feedback regulation.
In a hypothetical cell, the facilitated diffusion of a solute 'Y' is observed to be significantly faster than predicted by simple diffusion models. However, the transport rate plateaus at high concentrations of Y. Which of the following is the MOST likely explanation for this observation?
The cell membrane is selectively permeable to Y.
The solute Y is transported via carrier proteins.
The solute Y is undergoing active transport.
The cell is modifying Y during transport.
Which of the following statements regarding facilitated diffusion is INCORRECT?
It requires transport proteins.
It is a passive process and does not require energy.
It can move molecules against their concentration gradient.
Transport proteins involved can become saturated.
Which of the following is NOT a primary function of cell membrane proteins?
Transporting molecules across the membrane
Acting as receptors for signaling molecules
Synthesizing lipids
Providing structural support to the membrane
Which component of the cell membrane is primarily responsible for its selective permeability?
Glycoproteins
Peripheral proteins
Phospholipid bilayer
Cholesterol
In facilitated diffusion, molecules move across the membrane with the help of:
ATP hydrolysis
Membrane proteins
Concentration gradient against their movement
Vesicle formation
Which of the following is the primary component of the cell membrane?
Carbohydrates
Proteins
Nucleic acids
Phospholipids
The fluid mosaic model describes the cell membrane as:
A rigid, static layer
A solid barrier
A dynamic structure with embedded proteins
A single layer of phospholipids
