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Chapter 5
The Structure and Function of
Large Biological Molecules
PowerPoint® Lecture Presentations for
Biology
Eighth Edition
Neil Campbell and Jane Reece
Lectures by Chris Romero, updated by Erin Barley with contributions from Joan Sharp
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings
The Synthesis and Breakdown of Polymers
Animation: Polymers
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings
Fig. 5-2a Fill in the missing information.
HO
1
2
3
HO
H
Short polymer
Unlinked monomer
____________ removes a ______
molecule, forming a new bond
HO
1
2
H
3
_____
4
H
Longer polymer
(a) ____________ reaction in the synthesis of a _________
Fig. 5-3a Describe the 3 ways of classifying sugars.
Fig. 5-4 Start with the linear form of fructose (see figure 5.3) and draw the formation of the fructose ring in two steps.
Number the carbons. Attach carbon 5 via oxygen to carbon 2. Compare the number of carbons in the fructose and
glucose rings.
(a) Linear and ring forms
(b) Abbreviated ring structure
Animation: Disaccharides
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings
Fig. 5-6 What is the difference between plant starch and animal glycogen? How are they similar?
Chloroplast
Mitochondria Glycogen granules
Starch
0.5 µm
1 µm
Glycogen
Amylose
Amylopectin
(a) Starch: a plant polysaccharide
(b) Glycogen: an animal polysaccharide
Structural Polysaccharides
Animation: Polysaccharides
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings
Fig. 5-7a How are these glucose molecules different? Fill in the names of the glucose molecules.
Glucose
(a)
and
glucose ring structures
Glucose
Fig. 5-7bc How does the position of the OH affect an organism’s ability to digest the sugars below?
(b) Starch: 1–4 linkage of
glucose monomers
(c) Cellulose: 1–4 linkage of
glucose monomers
Fig. 5-8 How does the arrangement of glucose monomers relate to its function?
Cell walls
Cellulose
microfibrils
in a plant
cell wall
Microfibril
10 µm
0.5 µm
Cellulose
molecules
b Glucose
monomer
Fig. 5-9 Why can this cow digest cellulose while humans cannot?
Fig. 5-10 What makes chitin a unique type of carbohydrate?
(a) The structure
of the chitin
monomer.
(b) Chitin forms the
exoskeleton of
arthropods.
(c) Chitin is used to make
a strong and flexible
surgical thread.
Fig. 5-11b What do all lipids have in common?
Ester linkage
(b) Fat molecule (triacylglycerol)
Animation: Fats
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Fig. 5-12a How are these these lipids similar? Different?
Fig. 5-14 What direction do the hydrophobic tail point?
Hydrophilic
head
Hydrophobic
tail
WATER
WATER
Fig. 5-15 Why are steroids like this one considered a lipid?
Table 5-1 Why did the Greek used the word proteios to describe this macromolecule?
Animation: Structural Proteins
Animation: Storage Proteins
Animation: Transport Proteins
Animation: Receptor Proteins
Animation: Contractile Proteins
Animation: Defensive Proteins
Animation: Hormonal Proteins
Animation: Sensory Proteins
Animation: Gene Regulatory Proteins
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings
Animation: Enzymes
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings
Fig. 5-17a Explain why these R groups will not interact with charged molecules.
Nonpolar
Glycine
(Gly or G)
Methionine
(Met or M)
Alanine
(Ala or A)
Valine
(Val or V)
Phenylalanine
(Phe or F)
Leucine
(Leu or L)
Tryptophan
(Trp or W)
Isoleucine
(Ile or I)
Proline
(Pro or P)
Fig. 5-17b Explain why these R groups will interact with charged molecules.
Polar
Serine
(Ser or S)
Threonine
(Thr or T)
Cysteine
(Cys or C)
Tyrosine
(Tyr or Y)
Asparagine Glutamine
(Asn or N) (Gln or Q)
Fig. 5-17c Which type of charged molecules will acidic R groups interact with? Basic?
Electrically
charged
Acidic
Aspartic acid Glutamic acid
(Glu or E)
(Asp or D)
Basic
Lysine
(Lys or K)
Arginine
(Arg or R)
Histidine
(His or H)
Fig. 5-18 In (a), circle and label the carboxyl and amino groups that will form the peptide bond shown in (b).
Peptide
bond
(a)
Side chains
Peptide
bond
Backbone
(b)
Amino end
(N-terminus)
Carboxyl end
(C-terminus)
Four Levels of Protein Structure
Animation: Protein Structure Introduction
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings
Animation: Primary Protein Structure
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings
Fig. 5-21a Draw in the carboxyl end.
Primary Structure
1
+H
5
3N
Amino end
10
Amino acid
subunits
15
20
25
Animation: Secondary Protein Structure
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings
Fig. 5-21c Which areas of mino acids interact to form these structures?
Secondary Structure
pleated sheet
Examples of
amino acid
subunits
helix
Animation: Tertiary Protein Structure
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings
Fig. 5-21f Fill in
missing information.
Animation: Quaternary Protein Structure
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings
Fig. 5-22a What causes sickle-cell anemia?
Normal hemoglobin
Primary
structure
Val His Leu Thr Pro Glu Glu
1
2
Secondary
and tertiary
structures
3
4
5
6
7
subunit
Quaternary
structure
Normal
hemoglobin
(top view)
Function
Molecules do
not associate
with one
another; each
carries oxygen.
Fig. 5-23 What 3 aspects of the environment can cause a protein to denature?
Denaturation
Normal protein
Renaturation
Denatured protein
Fig. 5-24b What does the chaperonin provide the polypeptide ?
Correctly
folded
protein
Polypeptide
Steps of Chaperonin
Action:
1 An unfolded polypeptide enters the
cylinder from one end.
2 The cap attaches, causing the
cylinder to change shape in
such a way that it creates a
hydrophilic environment for
the folding of the polypeptide.
3 The cap comes
off, and the properly
folded protein is
released.
Fig. 5-25b If you were an author of the paper and were describing the model, what type of protein structure would you call the
small green polypeptide sp in the center?
RESULTS
RNA
polymerase II
DNA
RNA
Fig. 5-26-3 List the terms in the correct order as it is represented in this figure: Protein, DNA, RNA
DNA
1 Synthesis of
mRNA in the
nucleus
mRNA
NUCLEUS
CYTOPLASM
mRNA
2 Movement of
mRNA into cytoplasm
via nuclear pore
Ribosome
3 Synthesis
of protein
Polypeptide
Amino
acids
Fig. 5-27ab What part of a nucleotide can vary?
5' end
5'C
3'C
Nucleoside
Nitrogenous
base
5'C
Phosphate
group
5'C
3'C
(b) Nucleotide
3' end
(a) Polynucleotide, or nucleic acid
3'C
Sugar
(pentose)
Fig. 5-27c-1 How many carbon rings in pyrimidines? Purines?
Nitrogenous bases
Pyrimidines
Cytosine (C)
Thymine (T, in DNA)
Uracil (U, in RNA)
Purines
Adenine (A)
Guanine (G)
(c) Nucleoside components: nitrogenous bases
Fig. 5-27c-2 what carbon (1-5) holds the structural difference between the sugar in DNA and RNA?
Sugars
Deoxyribose (in DNA)
Ribose (in RNA)
(c) Nucleoside components: sugars
Fig. 5-28 Why is it called a double helix?
5' end
3' end
Sugar-phosphate
backbones
Base pair (joined by
hydrogen bonding)
Old strands
Nucleotide
about to be
added to a
new strand
3' end
5' end
New
strands
5' end
3' end
5' end
3' end