BIO 200 PRACTICE TEST QUESTIONS WITH VERIFIED
ANSWERS
What is the order of permeability in a lipid bilayer? - Answers - 1.) small, nonpolar
molecules
2.) small, polar molecules (uncharged)
3.) large, polar molecules (uncharged)
4.) ions
Explain what generally prevents substrates/reactants from interacting with each other in
the absence of an enzyme. Make sure to describe the role of energy, identifying the
type of energy involved - Answers - don't have enough activation energy to overcome
barrier
Where do the enzymes bind to to lower the activation energy? - Answers - enzymes
bind to the substrate to lower the activation energy
What are 6 main functions that proteins can perform? - Answers - 1.) structural support
2.) signalling
3.) movement
4.) defense
5.) catalysis
6.) transport of materials
Where do the enzymes bind to? - Answers - Enzymes bind to the substrates in a special
location on the enzyme called the active site
Why does the activation energy drop with the use of enzymes? Hint: think about what it
is doing to the bonds in the substrates - Answers - Enzymes destabilize bonds in the
substrates
When a reaction goes from nonpolar covalent to polar covalent, what type of reaction is
this? - Answers - exergonic reaction
When a reaction goes from polar covalent to nonpolar covalent, what type of reaction is
this? - Answers - endergonic reaction
Define hydrophobic interactions - Answers - very weak interactions btwn nonpolar
molecules when exposed to an aqueous solvent
Define plasma membrane - Answers - a membrane that surrounds the cell, separating it
from the external environment and selectively regulating the passage of molecules and
ions into and out of the cell
ANSWERS
What is the order of permeability in a lipid bilayer? - Answers - 1.) small, nonpolar
molecules
2.) small, polar molecules (uncharged)
3.) large, polar molecules (uncharged)
4.) ions
Explain what generally prevents substrates/reactants from interacting with each other in
the absence of an enzyme. Make sure to describe the role of energy, identifying the
type of energy involved - Answers - don't have enough activation energy to overcome
barrier
Where do the enzymes bind to to lower the activation energy? - Answers - enzymes
bind to the substrate to lower the activation energy
What are 6 main functions that proteins can perform? - Answers - 1.) structural support
2.) signalling
3.) movement
4.) defense
5.) catalysis
6.) transport of materials
Where do the enzymes bind to? - Answers - Enzymes bind to the substrates in a special
location on the enzyme called the active site
Why does the activation energy drop with the use of enzymes? Hint: think about what it
is doing to the bonds in the substrates - Answers - Enzymes destabilize bonds in the
substrates
When a reaction goes from nonpolar covalent to polar covalent, what type of reaction is
this? - Answers - exergonic reaction
When a reaction goes from polar covalent to nonpolar covalent, what type of reaction is
this? - Answers - endergonic reaction
Define hydrophobic interactions - Answers - very weak interactions btwn nonpolar
molecules when exposed to an aqueous solvent
Define plasma membrane - Answers - a membrane that surrounds the cell, separating it
from the external environment and selectively regulating the passage of molecules and
ions into and out of the cell
