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Section 1.3: The Carbon Chemistry of Life
Section 1.3 Questions, page 28
1. Carbon has four unpaired valence electrons allowing it to form four covalent bonds. Carbon
can Section
bond with one
two other
carbons
to form straight
1.3:orThe
Carbon
Chemistry
of chains.
Life When carbon bonds with three or
fourSection
other carbons,
each secondary
carbon
1.3 Questions,
page
28 can form a chain resulting in a branched chain. Due to
electron
repulsion,
the bonds
form
a tetrahedral
structure.
angles
the bonds
allow
1. Carbon
has four
unpaired
valence
electrons
allowingThe
it to
form between
four covalent
bonds.
Carbon
chains
carbon
bend
andcarbons
form ring
structures.
canofbond
withtoone
or around
two other
to form
straight chains. When carbon bonds with three or
2. Functional
areeach
specific
groupscarbon
of atoms
molecules
are responsible
four othergroups
carbons,
secondary
canwithin
form aorganic
chain resulting
in that
a branched
chain. Due to
for the
characteristic
chemical
reactions
of
those
molecules.
The
same
functional
group
will allow
electron repulsion, the bonds form a tetrahedral structure. The angles between the bonds
undergo
theofsame
or similar
reaction(s)
chains
carbon
to bendchemical
around and
form ringregardless
structures.of the size of the molecule it is a part
of. 2. Functional groups are specific groups of atoms within organic molecules that are responsible
3. Compounds
with similar
structures
often have
similar
uses. Their
is functional
dependent group
on the will
for the characteristic
chemical
reactions
of those
molecules.
The use
same
properties
of
the
compounds
and
the
properties
are
dependent
on
structures
of
the
compounds.
undergo the same or similar chemical reaction(s) regardless of the size of the molecule it is a part
4. Answers
may vary. Sample answer: Functional groups help determine if a molecule is polar or
of.
non-polar.
This
property
determines
the types
solvents
anduses.
molecules
thatisit dependent
is attractedon
to.the
For
3. Compounds
with similar
structures
oftenofhave
similar
Their use
example,
polarofsolvents
dissolve polar
and
ionic compounds
and non-polar
solvents
properties
the compounds
and the
properties
are dependent
on structures
of thedissolve
compounds.
non-polar
compounds.
4. Answers may vary. Sample answer: Functional groups help determine if a molecule is polar or
5. Answers
mayThis
vary.
Sampledetermines
answer: Inthe
many
functional
groups,
oxygen helps
the to. For
non-polar.
property
types
of solvents
and molecules
thatestablish
it is attracted
polarity
of thepolar
molecule.
In some
groups,
actscompounds
as a reducing
by losing
electrons
example,
solvents
dissolve
polaroxygen
and ionic
andagent
non-polar
solvents
dissolve
fromnon-polar
compounds
while in other groups, it acts as an oxidizing agent by gaining electrons to form
compounds.
a bond.
5. Answers may vary. Sample answer: In many functional groups, oxygen helps establish the
–
6. (a)
–CO2Hof+the
H2 O
 –CO2In
+some
H3O+groups, oxygen acts as a reducing agent by losing electrons
polarity
molecule.
The from
carboxyl
group loses
ion. it acts as an oxidizing agent by gaining electrons to form
compounds
whilea hydrogen
in other groups,
+
(b) –NH
a bond.
2 + H2O –NH3 + OH
–
The 6.
amino
group
gains a hydrogen
ion. +
(a) –CO
2H + H2O  –CO2 + H3O
–
–
2–
+
(c) –PO
H2 + OH group
–POloses
The4carboxyl
hydrogen
ion.
4H +aH
2O  –PO
4 + H3 O
+
The (b)
phosphate
–NH2 +group
H2Oloses
–NHa3 hydrogen
+ OH ion.
7. Answer
may group
vary. Sample
answer: Student
The amino
gains a hydrogen
ion. drawings should resemble Figure 6 on page 27 of
–
–
the student
textbook.
(c) –PO4H2 + OH –PO4H + H2O  –PO42– + H3O+
The phosphate group loses a hydrogen ion.
7. Answer may vary. Sample answer: Student drawings should resemble Figure 6 on page 27 of
the student textbook.
8. Dehydration synthesis and hydrolysis are both processes that rearrange molecules in organic
substances. Dehydration synthesis connects smaller molecules to form larger organic
compounds. Water is lost during the process. In hydrolysis, water is added and larger compounds
are broken
down into
smaller and
units.
8. Dehydration
synthesis
hydrolysis are both processes that rearrange molecules in organic
9. This
is an example
of hydrolysis
because
the products
are smallertothan
reactants
and water
substances.
Dehydration
synthesis
connects
smaller molecules
formthe
larger
organic
is added.
compounds. Water is lost during the process. In hydrolysis, water is added and larger compounds
10. Answers
may
vary.
Sample
answer:
are broken
down
into
smaller
units. Dehydration could be used to form longer and more
complex
polysaccharides
for
cell
function.
Hydrolysis
could be
to reduce
polysaccharides
9. This is an example of hydrolysis because
the products
areused
smaller
than the
reactants and water
into issimple
added.more easily utilized sugars.
10. Answers may vary. Sample answer: Dehydration could be used to form longer and more
complex polysaccharides for cell function. Hydrolysis could be used to reduce polysaccharides
Copyright
© 2012more
Nelson
Education
Ltd.sugars.
Chapter 1: The Biochemical Basis of Life 1.3-1
into simple
easily
utilized
Copyright © 2012 Nelson Education Ltd.
Chapter 1: The Biochemical Basis of Life 1.3-1