Transcript ch02-Chemistry-of

Chapter 2-- Study Guide
1. Critically read Chapter 2 pp. 59-69 before
“ENZYMES AND METABOLISM” section
2. Comprehend Terminology (those in bold in
the textbook)
3. Study-- Figure questions, Think About
It questions, and Before You Go On
(section-ending) questions
4. Do end-of-chapter questions:
– Testing Your Recall— 6 to 10, 15-17
– True or False– 1 3, 5, 6, 7
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§ 2.4 Organic Compounds
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§ Organic compounds —
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•
Def.--Compounds of carbon
The organic molecules of life— 4
groups: carbohydrates, lipids, . . .
•
Functional groups of organic
molecules— a group of atoms that
determines the functional
characteristics of an organic molecule
•
For example– Fig. 2.14
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(See next slide)
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ATP (adenosine triphosphate) ̶
A Nucleotide
three _______________ groups
Base;
adenine
Sugar; ribose
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§ Monomers and polymers —
•
•
•
Polymers– molecules made of a repetitive
series of identical or similar ___________
For example, starch is a polymer of about
3,000 glucose monomers
Mechanism (how?) by poly
____ –
this above process; also called dehydration
synthesis (OR condensation)
Fig. 2.15
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Which is polymerization
reaction, A or B?
A.
B.
Give an example of polymerization.
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§ Carbohydrates —
•
•
•
Hydrophilic molecules– Why?
General formula (CH2O)n
1. Monosaccharides (simple sugars)—
glucose, fructose, and galactose;
isomers of each other (C6H12O6)
Fig. 2.16
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Where are
carbon
atoms?
Fig. 2.16-- Three
monosaccharides;
hydroxyl groups?
Disaccharides-next slide 9
Glucose +
Fructose
2. Disaccharides
Milk
sugar
A product
of starch
digestion
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3A. Polysaccharide–
long chains of glucose
(Glucose, glu.)
Starch and
cellulose
next slide
Glu.
Glu.
Glu.
Glu.
Can we make
glycogen?
Glu.
Glu.
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§ Carbohydrates (continued)—
•
•
•
•
3B. Other polysaccharides–
Starch—energy-storing molecules in
plants; when sunlight + nutrients is not
available, plants use starch as energy
C____________—structural molecule of
cell walls; can we digest it? Why?
For example, wood, cotton etc.
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§ Carbohydrates (continued)—
• 4. conjugated carbohydrates–
•
•
•
Bound to proteins (a) & lipids
(glycolipids, cell surface coat)
Example— a. glycoproteins; major
component of mucus; where?
b. Proteoglycans– hold cells and
tissues together; gelatinous filler in
the eye; in the joints etc.
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Review Table 2.6, a summary
of carbohydrate functions:
1. Monosaccharides
2. Disaccharides
3. Polysaccharides
4. Conjugated carbohydrates
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§ Lipids —
•
•
•
Hydrophobic molecules; Why?
Include C, H, and O; with high ratio of
hydrogen to oxygen
Ex. C57H110O6 (tristearin) vs. (CH2O)n
Less oxidized than carbohydrates;
more calories per gram
•
Several major types of lipids in
humans
Table 2.7
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Steroids
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Glycerol
Is this a
dehydration
synthesis or
hydrolysis
reaction?
1.--3
Fatty
acids
2.--Triglyceride synthesis
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

Next
slide
3.--Fig. 2.20
Lecithin, a
phospholipid
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Fig. 2.20c– A simplified
representation of the
phopholipid molecule
Why is a phospholipid
amphiphilic?
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4.--Fig. 2.21 A prostaglandin, Eicosanoids
•Five of the carbon atoms are arranged in a ring.
•Functions--
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5.—Fig. 2.22 Cholesterol
All steroids have
this basic fourringed structure.
Functions—? Next
slide
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5.--Cholesterol —
1. (Where?) Cholesterol is found only in
animals (natural product); from where?
2. Related to cardiovascular disease
(INSIGHT 2.3—Good and bad
cholesterol; p. 76)
3. Function-–
–
Precursor of steroids
Important component of cell membrane
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§ Amino acids & proteins —
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•
•
A protein is a polymer of amino acids
A amino acid has a central carbon
atom with an amino and a carboxyl
group bound to it
The radical (R) group makes each of
the 20 amino acid unique
Essential a.a.--?
Fig. 2.23
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Similarities
of all a.a.?
R groups
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§ Amino acids & proteins
(continued)—
•
Joining of amino acids– by peptide
bonds– to form peptides
Fig. 2.23, 2.25
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a.a. #2
Is this a dehydration
synthesis or hydrolysis
reaction?
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§ Protein structure
Fig. 2.25
primary
structure of
insulin
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§ Amino acids & proteins
(continued)—
•
Tertiary structure– folding into
globular and fibrous shapes
–
–
Globular proteins– a ball of yarn;
Ex. enzymes and antibodies
Fibrous proteins– slender filaments;
muscle contraction proteins--
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§ Protein functions—
1. Structure– Keratin gives strength to
nails, hair, and skin surface
2. Communication– oxytocin (a ligand)
binds to a protein (its receptors)
3. Membrane transport channels—
Sodium and potassium channels
4. Catalysis– enzymes
etc.
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Check Point Questions
A. Use the simplified phospholipids
(each with a head and two wavy
tails) to construct a portion of a cell
membrane.
B. Point out the polar region and the
nonpolar regions.
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