BICH 410 CHAPTER 2 (CARR) EXAM QUESTIONS WITH CORRECT ANSWERS LATEST UPDATE 2026
Covalent Bonds - Answers a bond formed by the sharing of one or more electron pairs between two
atoms
Examples of Covalent Bonds - Answers O-H
C-H
C-C
Ice vs. Liquid water - Answers ICE: water molecules are hydrogen bonded in crystalline array
LIQUID: hydrogen bonds rapidly break and re-form, in irregular networks
Weak Forces - Answers create interactions that are constantly forming and breaking under
physiological conditions
Why do we not use strong interactions biologically? - Answers Function requires dynamics, and strong
interactions would paralyze function
The attractive forces acting on biological molecules are..? - Answers -ionic interactions
-hydrogen bonds
-van der Waals interactions
Amphiphilic/Amphipathic molecules - Answers interact favorably with favorably with both polar and
non polar environments
What do amphiphilic substances form? - Answers they form micelles or bilayers that hide their
hydrophobic groups while exposing their hydrophilic groups to water
Examples of Amphipathic molecules - Answers fatty acids and detergents
Hydrophobic Effect - Answers the tendency of non-polar substances to aggregate in aqueous solution
and exclude water
How does the hydrophobic effect relate to entropy? - Answers When non-polar molecules coalesce
the entropy of the solvent (water) increases. This is because the exclusion of water molecules means
the water molecules have more degrees of freedom. They have more directions they can move so
that means entropy has been created.
What type of substances can dissolve in water? - Answers polar and ionic substances
What does the hydrophobic effect explain? - Answers that the exclusion of non-polar groups is a way
to maximize the entropy of water molecules
Do non-polar substances dissolve in water? - Answers NO!!!!!
What happens in OSMOSIS? - Answers molecules diffuse across membranes which are permeable to
them from regions of higher concentration to regions of lower concentration
osmosis = trying to reach equilibrium
What happens in DIALYSIS? - Answers diffusion of solutes across a semipermeable membrane from
regions of higher concentration to regions of lower concentration
What makes water polar? - Answers bent structure and polar covalent bonds
{if water was straight, charges would cancel out}
How many H-bonds per water molecule? - Answers 4
H-bonds of ICE? - Answers 4 H-bonds per water molecule
H-bonds of WATER (liquid)? - Answers 2-3 H-bonds per water molecule at any given time
*bonds of liquid water are too transient to from all 4 at once
*also* liquid water packs in more conformations, more closely, in higher density than solid water...
this is why we can ice skate
Fluidity of water? - Answers fluid network of H-bonds that attract water molecules... its all about
changing partners
What makes water a good solvent for polar molecules? - Answers its high dielectric constant
What is the hydration shell? - Answers a chemical structure that surrounds a solute in a solution in
which the solvent is water
The H's of water can bond with? - Answers -hydroxyl groups
-carbonyl groups [good H+ acceptor]
-carboxyl groups [O- makes it an acid]
-amine groups [good H+ donors]
Covalent Bonds - Answers a bond formed by the sharing of one or more electron pairs between two
atoms
Examples of Covalent Bonds - Answers O-H
C-H
C-C
Ice vs. Liquid water - Answers ICE: water molecules are hydrogen bonded in crystalline array
LIQUID: hydrogen bonds rapidly break and re-form, in irregular networks
Weak Forces - Answers create interactions that are constantly forming and breaking under
physiological conditions
Why do we not use strong interactions biologically? - Answers Function requires dynamics, and strong
interactions would paralyze function
The attractive forces acting on biological molecules are..? - Answers -ionic interactions
-hydrogen bonds
-van der Waals interactions
Amphiphilic/Amphipathic molecules - Answers interact favorably with favorably with both polar and
non polar environments
What do amphiphilic substances form? - Answers they form micelles or bilayers that hide their
hydrophobic groups while exposing their hydrophilic groups to water
Examples of Amphipathic molecules - Answers fatty acids and detergents
Hydrophobic Effect - Answers the tendency of non-polar substances to aggregate in aqueous solution
and exclude water
How does the hydrophobic effect relate to entropy? - Answers When non-polar molecules coalesce
the entropy of the solvent (water) increases. This is because the exclusion of water molecules means
the water molecules have more degrees of freedom. They have more directions they can move so
that means entropy has been created.
What type of substances can dissolve in water? - Answers polar and ionic substances
What does the hydrophobic effect explain? - Answers that the exclusion of non-polar groups is a way
to maximize the entropy of water molecules
Do non-polar substances dissolve in water? - Answers NO!!!!!
What happens in OSMOSIS? - Answers molecules diffuse across membranes which are permeable to
them from regions of higher concentration to regions of lower concentration
osmosis = trying to reach equilibrium
What happens in DIALYSIS? - Answers diffusion of solutes across a semipermeable membrane from
regions of higher concentration to regions of lower concentration
What makes water polar? - Answers bent structure and polar covalent bonds
{if water was straight, charges would cancel out}
How many H-bonds per water molecule? - Answers 4
H-bonds of ICE? - Answers 4 H-bonds per water molecule
H-bonds of WATER (liquid)? - Answers 2-3 H-bonds per water molecule at any given time
*bonds of liquid water are too transient to from all 4 at once
*also* liquid water packs in more conformations, more closely, in higher density than solid water...
this is why we can ice skate
Fluidity of water? - Answers fluid network of H-bonds that attract water molecules... its all about
changing partners
What makes water a good solvent for polar molecules? - Answers its high dielectric constant
What is the hydration shell? - Answers a chemical structure that surrounds a solute in a solution in
which the solvent is water
The H's of water can bond with? - Answers -hydroxyl groups
-carbonyl groups [good H+ acceptor]
-carboxyl groups [O- makes it an acid]
-amine groups [good H+ donors]
