IGNOU MSc Zoology | Tutor Marked Assignment (TMA) | Solved Answers for Academic Reference
The Lineweaver–Burk plot is a double reciprocal graph used to analyze enzyme kinetics. It is obtained by plotting 1/V against 1/[S]. It is derived from the Michaelis–Menten equation by taking the reciprocal of both sides. This plot helps in determining Km and Vmax values accurately.
Km represents the substrate concentration at which reaction velocity is half of Vmax and indicates enzyme affinity for substrate. Vmax represents the maximum velocity achieved at saturation. Together, they help understand enzyme efficiency and behavior.
| Competitive Inhibition | Non-Competitive Inhibition |
|---|---|
| Inhibitor competes with substrate | Inhibitor binds at different site |
| Km increases | Vmax decreases |
| Artery | Vein |
|---|---|
| Carry blood away from heart | Carry blood toward heart |
| Thick muscular walls | Thin walls with valves |
| Active Transport | Passive Transport |
|---|---|
| Requires ATP | No energy required |
| Against gradient | Along gradient |
Enzymes have an optimum pH and temperature at which they function best. Extreme pH or temperature alters enzyme structure, leading to reduced activity or denaturation.
The active site is a specific region of enzyme where substrate binds. It is highly specific, three-dimensional, and stabilized by weak interactions.
Well-Fed State: A metabolic condition after food intake characterized by high insulin levels.
Allosteric Enzymes: Enzymes regulated by molecules binding at sites other than active site.
Malpighian Tubules: Excretory organs of insects involved in osmoregulation.
Filter Feeding: Feeding mechanism where suspended particles are filtered from water.
Standard Gibbs Energy Change: Indicates spontaneity of biochemical reactions under standard conditions.
Nernst Equation: Relates redox potential to concentration of oxidized and reduced species.
ATP as Energy Currency: ATP stores and transfers energy through high-energy phosphate bonds.
Electron Transport Chain: Protein complexes transfer electrons and generate proton gradient.
Proton Gradient: Drives ATP synthesis through chemiosmosis.
Insulin/Glucagon Ratio: Low blood glucose increases glucagon and decreases insulin.
Respiratory Response: Lungs adapt to extreme conditions by altering breathing rate and oxygen uptake.
Muscle Contraction: Occurs by sliding filament mechanism involving actin and myosin.
ATP in Muscle: ATP is used for contraction, ion transport and recovery.
Absorption in Large Intestine: Water and electrolytes are absorbed, forming feces.
F0-F1 ATP Synthase: Enzyme complex synthesizing ATP using proton gradient.
Redox Potential: Measures tendency of a substance to gain or lose electrons.