16 public questions tagged with this topic.
The sodium-potassium pump actively transports ions using ATP, preventing free movement across the membrane.
Ref: NCERT Class 11 Biology Chapter 18: Neural Control and Coordination Sensory Organs - Eye - Structure and Physiology of Vision
Phospholipids are structural components of membranes but do not store genetic information.
Ref: NCERT Class 11 Biology Chapter 9: Biomolecules Enzyme Action and Factors Affecting Enzyme Activity
Phospholipids form the bilayer structure of cell membranes, contributing to their fluidity and integrity.
Ref: NCERT Class 11 Biology Chapter 9: Biomolecules Enzyme Action and Factors Affecting Enzyme Activity
Phospholipids are a key structural component of cell membranes, forming the lipid bilayer.
Ref: NCERT Class 11 Biology Chapter 9: Biomolecules Enzyme Action and Factors Affecting Enzyme Activity
Phospholipids are key structural components of cell membranes, forming the lipid bilayer.
Ref: NCERT Class 11 Biology Chapter 9: Biomolecules Enzyme Action and Factors Affecting Enzyme Activity
Phospholipids form the bilayer structure of cell membranes but do not contain peptide bonds or store genetic information.
Ref: NCERT Class 11 Biology Chapter 9: Biomolecules Chemical Analysis and Biomolecules - Amino Acids Lipids
The tonoplast transports several ions and other materials into the vacuole against concentration gradients. Loss of this function would prevent the vacuole from maintaining concentrations significantly higher than those in the cytoplasm.
Ref: NCERT Class 11 Biology Chapter 8: Cell: The Unit of Life Mitochondria Plastids Ribosomes and Other Organelles
Detailed membrane structure became accessible with electron microscopy, while chemical and biochemical studies—especially of erythrocyte membranes—revealed lipids, proteins, cholesterol and carbohydrates. Together, these findings supported models of bilayer organisation and membrane proteins.
Ref: NCERT Class 11 Biology Chapter 8: Cell: The Unit of Life Eukaryotic Cell - Cell Wall and Cell Membrane - Fluid Mosaic Model
Cell membranes mainly contain lipids and proteins, and also possess cholesterol and carbohydrates. Different cell types may contain these basic components in different proportions, so their protein-to-lipid ratios need not be identical.
Ref: NCERT Class 11 Biology Chapter 8: Cell: The Unit of Life Eukaryotic Cell - Cell Wall and Cell Membrane - Fluid Mosaic Model
Membrane fluidity results from lateral movement of proteins within the quasi-fluid lipid bilayer. This property is important in cell growth, formation of intercellular junctions, secretion, endocytosis and cell division.
Ref: NCERT Class 11 Biology Chapter 8: Cell: The Unit of Life Eukaryotic Cell - Cell Wall and Cell Membrane - Fluid Mosaic Model
Polar molecules cannot pass readily through the non-polar interior of the lipid bilayer. They therefore require membrane carrier proteins to facilitate their movement across the plasma membrane.
Ref: NCERT Class 11 Biology Chapter 8: Cell: The Unit of Life Eukaryotic Cell - Cell Wall and Cell Membrane - Fluid Mosaic Model
The plasma membrane is selectively permeable, allowing only certain molecules or ions to move across it. Substances may cross by passive transport, facilitated transport or active transport.
Ref: NCERT Class 11 Biology Chapter 8: Cell: The Unit of Life Cell Theory and Overview of Cell
