Understandings:
1.3.U1: Phospholipids form bilayers in water due to the amphipathic properties of phospholipid molecules. [Amphipathic phospholipids have hydrophilic and hydrophobic properties.]
1.3.U2: Membrane proteins are diverse in terms of structure, position in the membrane and function.
1.3.U3: Cholesterol is a component of animal cell membranes.
Applications:
1.3.A1: Cholesterol in mammalian membranes reduces membrane fluidity and permeability to some solutes.
Skills:
1.3.S1: Drawing of the fluid mosaic model. [Drawings of the fluid mosaic model of membrane structure can be two dimensional rather than three dimensional. Individual phospholipid molecules should be shown using the symbol of a circle with two parallel lines attached. A range of membrane proteins should be shown including glycoproteins.]
1.3.S2: Analysis of evidence from electron microscopy that led to the proposal of the Davson-Danielli model.
1.3.S3: Analysis of the falsification of the Davson-Danielli model that led to the Singer-Nicolson model.
1.3.NOS1: Using models as representations of the real world-there are alternative models of membrane structures.
1.3.NOS2: Falsification of theories with one theory being superseded by another-evidence falsified the Davson-Danielli model.
[Text in square brackets indicates guidance notes]
1.3.U1: Phospholipids form bilayers in water due to the amphipathic properties of phospholipid molecules. [Amphipathic phospholipids have hydrophilic and hydrophobic properties.]
1.3.U2: Membrane proteins are diverse in terms of structure, position in the membrane and function.
1.3.U3: Cholesterol is a component of animal cell membranes.
Applications:
1.3.A1: Cholesterol in mammalian membranes reduces membrane fluidity and permeability to some solutes.
Skills:
1.3.S1: Drawing of the fluid mosaic model. [Drawings of the fluid mosaic model of membrane structure can be two dimensional rather than three dimensional. Individual phospholipid molecules should be shown using the symbol of a circle with two parallel lines attached. A range of membrane proteins should be shown including glycoproteins.]
1.3.S2: Analysis of evidence from electron microscopy that led to the proposal of the Davson-Danielli model.
1.3.S3: Analysis of the falsification of the Davson-Danielli model that led to the Singer-Nicolson model.
1.3.NOS1: Using models as representations of the real world-there are alternative models of membrane structures.
1.3.NOS2: Falsification of theories with one theory being superseded by another-evidence falsified the Davson-Danielli model.
[Text in square brackets indicates guidance notes]