Biology Essay Questions
Sample essays and suggested plans for content
1. The process of diffusion and its importance in living organisms
Definition
Fick’s Law
Types of diffusion e.g. Facilitated diffusion, osmosis
Gas exchange in unicells, fish, mammals and plants
Digestion and absorption of products
Exchange of materials between blood in capillaries and tissues e.g. placenta
Transpiration, root pressure, water and ion uptake by roots
Translocation and mass flow hypothesis
Osmoregulation by blood and kidney, unicells e.g. Amoeba
Action potentials
Synaptic transmission
Muscle action
Intracellular diffusion e.g. mitochondria, chloroplasts, enzyme action, DNA replication and protein synthesis
2. The different ways in which organisms use ATP OR ATP and its roles in living organisms
The nature/structure of ATP and its importance as energy currency.
Production and use of ATP in cytoplasm by glycolysis
Production of ATP by mitochondria in Krebs cycle and ETS – aerobic respiration.
Anaerobic respiration.
Role of chloroplasts in ATP production via light independent reaction
Uses e.g. Active transport (carrier protein shape changes), Nerve action (maintaining resting potentials via Na+/K+ pump and resynthesis of ACh), selective reabsorption by nephron, absorption by gut, Calvin cycle, muscle contraction (cross bridge formation), Biosynthesis of organic compounds, Contractile vacuoles, Translocation (loading of phloem), cell division
(movement of chromosomes via spindle), CP formation in muscles, Nitrogen fixation (Bluegreen algae), Kidney function, movement of sperm, secretion of digestive enzymes in saprophytic fungi, cilia and flagella action
3. The movement of substances within living organisms (Jan 2003) OR Transport mechanisms in living organisms
Diffusion e.g. Ion movement in Roots, Synapse, within a cell, O2/CO2 in lungs and gills, factors affecting rate
Facilitated diffusion e.g. Glucose uptake, action potentials
Osmosis e.g. Turgidity, uptake of water in
1. The process of diffusion and its importance in living organisms
Definition
Fick’s Law
Types of diffusion e.g. Facilitated diffusion, osmosis
Gas exchange in unicells, fish, mammals and plants
Digestion and absorption of products
Exchange of materials between blood in capillaries and tissues e.g. placenta
Transpiration, root pressure, water and ion uptake by roots
Translocation and mass flow hypothesis
Osmoregulation by blood and kidney, unicells e.g. Amoeba
Action potentials
Synaptic transmission
Muscle action
Intracellular diffusion e.g. mitochondria, chloroplasts, enzyme action, DNA replication and protein synthesis
2. The different ways in which organisms use ATP OR ATP and its roles in living organisms
The nature/structure of ATP and its importance as energy currency.
Production and use of ATP in cytoplasm by glycolysis
Production of ATP by mitochondria in Krebs cycle and ETS – aerobic respiration.
Anaerobic respiration.
Role of chloroplasts in ATP production via light independent reaction
Uses e.g. Active transport (carrier protein shape changes), Nerve action (maintaining resting potentials via Na+/K+ pump and resynthesis of ACh), selective reabsorption by nephron, absorption by gut, Calvin cycle, muscle contraction (cross bridge formation), Biosynthesis of organic compounds, Contractile vacuoles, Translocation (loading of phloem), cell division
(movement of chromosomes via spindle), CP formation in muscles, Nitrogen fixation (Bluegreen algae), Kidney function, movement of sperm, secretion of digestive enzymes in saprophytic fungi, cilia and flagella action
3. The movement of substances within living organisms (Jan 2003) OR Transport mechanisms in living organisms
Diffusion e.g. Ion movement in Roots, Synapse, within a cell, O2/CO2 in lungs and gills, factors affecting rate
Facilitated diffusion e.g. Glucose uptake, action potentials
Osmosis e.g. Turgidity, uptake of water in