Bmsc 200 (Slide 2) - Water, Weak Interactions and Buffers

tasnimjaisee's version from 2017-09-18 16:04


Question Answer
What is the most abundant molecule in living organisms?Water
Passive role of waterStructure of biomolecules are formed in response to water interactions
Active role of waterParticipates in many biochemical reactions
Water vs. Oxygen: Which is more electronegative?Oxygen
Dipole of water will dictate it’s ability to?form electrostatic interactions and hydrogen bonds
Hydrogen bondselectrostatic interactions of electronegative atom with hydrogen linked (donor) to another electronegative atom with a free electron pair (acceptor)
Most common hydrogen bond donors and acceptors within biomolecules?Oxygen - Nitrogen
Hydrogen bonds are double the length of?Covalent bonds
Strength of hydrogen bond depends on?Geometry
Are hydrogen bonds strong?No, they are non-covalent and weak
How much strength do hydrogen bonds have in %?5% strength of covalent bonds
Hydrogen bonds in water contributes to?Heat of vaporization and specific heat capacity of water
Heat of VaporizationHeat required vaporizing liquid at boiling
Specific Heat CapacityHeat required raising temperature of substance 1 degree
Water has a higher ____ than common solventsmelting point boiling point and heat of vaporization
IsothermicMost living organisms needing to regulate their temperatures
What helps us to stay cool?high composition of water within our bodies, coupled with high specific heat capacity of water
Ice propertiesH2O molecules participates in 4 H bonds with other H2O bonds
Why is water an effective hydrogen-bonder?Accepts/donates H bonds - Small size
How do water molecules interact and dissolve charged solutes?Formation of layers of hydration
Solubility depends on?Ability to interact with water molecules
Which molecules have the greatest solubility in water?Carry a charge - Hydrogen bonds
Hydrophilic (water-loving)Polar
Hydrophobic (water-fearing)Non-polar
Amphipathichydrophobic and hydrophilic portions (e.g. fatty acids)
Why are specialized transport proteins and strategies are required?For non-polar gasses with limited solubility in water (blood)
When an amphipathic compound mixes with water?nonpolar regions cluster together presenting smallest hydrophobic surface to water
Hydrophobic interactionsForces that hold non-polar regions of molecule
Hydrophobic driveforce in formation and stabilization of biomolecular structures and interactions
Non-covalent forces influenceFormation & stabilization of biomolecule structures - biomolecule interactions - Reactant-Enzyme binding
Non-covalent importance to biomolecules?H-Bonds - Interactions: Iconic, Hydrophobic & van der Waals
These groups can form hydrogen bonds withWater, intramolecular & intermolecular
Hydrogen bonds are critical for?Biomolecular interactions
In unfolded state hydrogen bond with water is?Perfect hydrogen bonder; Little is to be gained with formation of higher order structures
Electrostatic interactions between charged groups can be?attractive or repulsive
Magnitude of contribution of ionic interactions to biomolecular structures is greatly reduced by?Shielding of these groups by water molecules
Strength of electrostatic interactions depends on?Distance separating atoms and nature of the intervening medium
When do electron clouds influence each other?2 uncharged atoms are brought very close together
Interaction between permanent and induced dipolesshort range - low magnitude interactions.
Abundant in the core of protein causes?close packing of hydrophobic side chains
What happens when 2 atoms are separated by the sum of the van der Waals radii?Attraction is maximal
Van der Waals contact2 surfaces of complementary shapes come together
Hydrophobic EffectNon-polar molecule interaction - Nonpolar chains stay in protein away from water - Polar and charged side facing water - Large determinant biomolecules
Thermodynamics of the Hydrophobic Effect???
Low pH meansHigh protnated form