Download Unit 2

Unit 2
Objectives
Many of these items will not be overed in lecture since you should already know from basic
chemistry.
I)
Elements and Compounds
A) Distinguish between an element and a compound.
B) Identify the four elements that make up 96% of living matter.
C) Define the term trace element and give an example.
II)
Atoms and Molecules
A) Draw and label a simplified model of an atom. Explain how this model simplifies our
understanding of atomic structure.
B) Distinguish between each of the following pairs of terms:
i)
neutron and proton
ii)
atomic number and mass number
iii)
atomic weight and mass number
iv)
Explain how the atomic number and mass number of an atom can be used to
determine the number of neutrons.
C) Explain how two isotopes of an element are similar. Explain how they are different.
D) Describe two biological applications that use radioactive isotopes.
E) Define the terms energy and potential energy. Explain why electrons in the first electron
shell have less potential energy than electrons in higher electron shells.
F) Distinguish among nonpolar covalent, polar covalent and ionic bonds.
G) Explain why strong covalent bonds and weak bonds are both essential in living organisms.
H) Distinguish between hydrogen bonds and van der Waals interactions.
I) Give an example that illustrates how a molecule’s shape can determine its biological
function.
J) Explain what is meant by a chemical equilibrium.
III)
Metabolism, Energy, and Life
A) Explain the role of catabolic and anabolic pathways in cellular metabolism.
B) Distinguish between kinetic and potential energy.
C) Explain why an organism is considered an open system.
D) Explain the first and second laws of thermodynamics in your own words.
E) Explain why highly ordered living organisms do not violate the second law of
thermodynamics.
F) Write and define each component of the equation for free-energy change.
G) Distinguish between exergonic and endergonic reactions in terms of free energy change.
H) Explain why metabolic disequilibrium is one of the defining features of life.
I) List the three main kinds of cellular work. Explain in general terms how cells obtain the
energy to do cellular work.
IV)
The Properties of Water
A) With the use of a diagram or diagrams, explain why water molecules are:
i)
Polar
ii)
capable of hydrogen bonding with four neighboring water molecules
B) List four characteristics of water that are emergent properties resulting from hydrogen
bonding.
C) Define cohesion and adhesion. Explain how cohesion and adhesion contribute to the
movement of water from the roots to the leaves of a tree.
D) Explain the following observations by referring to the properties of water:
i)
Coastal areas have milder climates than adjacent inland areas.
ii)
Ocean temperatures fluctuate much less than air temperatures on land.
iii)
Insects like water striders can walk on the surface of a pond without breaking the
surface.
iv)
E)
F)
V)
VI)
A)
B)
C)
D)
E)
If you slightly overfill a water glass, the water will form a convex surface above the
top of the glass.
v)
If you place a paper towel so that it touches spilled water, the towel will draw in the
water.
vi)
Ice floats on water.
vii)
Humans sweat and dogs pant to cool themselves on hot days.
Distinguish between a solute, a solvent, and a solution.
Distinguish between hydrophobic and hydrophilic substances.
Explain how you would make up a one molar (1M) solution of ethyl alcohol.
The Dissociation of Water Molecules
Name the products of the dissociation of water and give their concentration in pure water.
Define acid, base, and pH.
Explain how acids and bases may directly or indirectly alter the hydrogen ion concentration
of a solution.
Using the bicarbonate buffer system as an example, explain how buffers work.
Briefly explain the causes and effects of acid precipitation.
Key Terms
anion
atom
atomic mass
atomic nucleus
atomic number
cation
chemical bond
chemical equilibrium
chemical reaction
compound
covalent bond
dalton
electron
electron shell
electronegativity
element
energy
energy level
hydrogen bond
ion
ionic bond
ionic compound
isotope
mass number
matter
molecular formula
molecule
neutron
nonpolar covalent bond
orbital
periodic table of the elements
polar covalent bond
potential energy
product
proton
radioactive isotope
reactant
salt
structural formula
trace element
valence
valence electron
valence shell
van der Waals interactions
activation energy
anabolic pathway
ATP (adenosine triphosphate)
bioenergetics
catabolic pathway
catalyst
chemical energy
endergonic reaction
energy
energy coupling
entropy
first law of thermodynamics
free energy
free energy of activation
heat
kinetic energy
metabolic pathway
metabolism
phosphorylated
potential energy
second law of thermodynamics
thermal energy
thermodynamics