QUIZ 1 BIOL340 EXAM QUESTIONS AND ANSWERS WITH
COMPLETE SOLUTIONS GRADED A++ LATEST UPDATE
Cell membranes Definition
Any membrane found in a cell, including the plasma membrane (PM) and many other
membranes surrounding organelles and cytoplasmic structures, which creates
compartments
Membrane functions (7)
- Compartmentalization (closing off small areas of cell to be specialised for functions)
- Scaffold for biochemical activities
- Selectively permeable barrier (NOT to water)
- Transporting solutes
- Responding to external signals (hormones, neurotransmitters, nerve impulses)
- Intracellular interaction (sensing molecules)
- Energy transduction
Membrane domains and cell polarity (4)
- Apical plasma membrane (regulation of nutrient and water intake, Regulated secretion,
Protection)
- Lateral plasma membrane (Cell contact and adhesion, Cell communication)
- Basal membrane (Generation of ion gradients, Integrins are involved in the interaction
between columnar cells at the base and the basal membrane)
, - Sides of cell (Variety of different junctions that function to prevent solutes from moving
across basal lamina
Cell membrane acts as a physical and chemical barrier
- Barrier between cell and the environment
- Attachment site of intracellular cytoskeleton
- Made up largely of proteins and lipids, but maybe also carbohydrates (glycoproteins
and glycolipids)
Lipids: Phospholipids (5)
- Most abundant type
- Phosphoglycerides (Glycerol backbone)
- Sphingolipids (Sphingosine backbone)
- Polar head group (Hydrophilic)
- Fatty acid chains (Hydrophobic)
Lipids: Cholesterol (5)
- Polar head group (directed to outside of membrane) and fatty acid chain as well
- Type of sterol
- Found in all animal cells, packed in between major lipids forming the membrane
- Increases fluidity of membranes
- Important in the formation of 'lipid rafts' (Uneven distribution of lipids and proteins with
membranes, Lipid rafts have high levels of sphingolipids and cholesterol and they
Localise proteins into 'microdomains')
Saturation vs unsaturation
COMPLETE SOLUTIONS GRADED A++ LATEST UPDATE
Cell membranes Definition
Any membrane found in a cell, including the plasma membrane (PM) and many other
membranes surrounding organelles and cytoplasmic structures, which creates
compartments
Membrane functions (7)
- Compartmentalization (closing off small areas of cell to be specialised for functions)
- Scaffold for biochemical activities
- Selectively permeable barrier (NOT to water)
- Transporting solutes
- Responding to external signals (hormones, neurotransmitters, nerve impulses)
- Intracellular interaction (sensing molecules)
- Energy transduction
Membrane domains and cell polarity (4)
- Apical plasma membrane (regulation of nutrient and water intake, Regulated secretion,
Protection)
- Lateral plasma membrane (Cell contact and adhesion, Cell communication)
- Basal membrane (Generation of ion gradients, Integrins are involved in the interaction
between columnar cells at the base and the basal membrane)
, - Sides of cell (Variety of different junctions that function to prevent solutes from moving
across basal lamina
Cell membrane acts as a physical and chemical barrier
- Barrier between cell and the environment
- Attachment site of intracellular cytoskeleton
- Made up largely of proteins and lipids, but maybe also carbohydrates (glycoproteins
and glycolipids)
Lipids: Phospholipids (5)
- Most abundant type
- Phosphoglycerides (Glycerol backbone)
- Sphingolipids (Sphingosine backbone)
- Polar head group (Hydrophilic)
- Fatty acid chains (Hydrophobic)
Lipids: Cholesterol (5)
- Polar head group (directed to outside of membrane) and fatty acid chain as well
- Type of sterol
- Found in all animal cells, packed in between major lipids forming the membrane
- Increases fluidity of membranes
- Important in the formation of 'lipid rafts' (Uneven distribution of lipids and proteins with
membranes, Lipid rafts have high levels of sphingolipids and cholesterol and they
Localise proteins into 'microdomains')
Saturation vs unsaturation
