2. Molecular Biology Flashcards
The carbon compounds which life are based on…
Carbohydrates, lipids, proteins, nucleic acids
Metabolism
The sum total of all chemical reactions that occur within a living organism
- enzyme catalysed reactions
Anabolism
Synthesis of more complex molecules from simpler molecules
Catabolism
Breakdown of complex molecules into simpler molecules
Four properties of water
Cohesive, Adhesive, Thermal (high specific heat capacity) and excellent solvent properties
Importance of water for living things
- As a coolant from sweating
- Transpiration in plants- pull up xylem by surface tension and capillary action
- Transport of many substances in blood
- Stable environment for aquatic organisms
Effect of temperature on enzyme activity
Increases up to optimum temperature, then decreases rapidly due to denaturation
Effect of pH on enzyme activity
Each enzyme has its optimum pH where its activity is highest
Moving outside optimal pH range- enzyme shape altered, diminishing enzyme activity
Effect of substrate concentration on enzyme activity
Increase in rate of reaction with increase in sub concentration
Increase is halted at Vmax (maximal RoR) where all active sites are occupied by substrates - saturated environment
Further increase in concentration will not increase RoR
Condensation reaction
Two smaller organic molecules combine to form a larger molecule with water produced as a by-product
Hydrolysis reaction
Breaking of chemical bonds by the addition of water molecules
Advantages of the immobilization of lactase in alginate beads
the enzyme can be easily separated from the milk and reused if it is immobilized
Give 5 examples of proteins and brief description
Insulin- hormone released to lower glucose levels in blood
Rubisco- enzyme involved in photosynthesis- fix carbon to RuBP
Spider silk- fibrous protein, long and very strong
Enzymes- globular protein that catalyses reactions
Rhodopsin- a sensitive pigment found in retina cells
Semi-conservative replication
In a new DNA molecule: one strand will always be from the original template molecule. The other strand will be newly synthesised
Transcription
The creation of a single mRNA strand from a DNA strand
