Review Chapters 16-27
Chapter 16: Molecular Genetics

You Must Know:
◦ The structure of DNA
◦ The major steps in replication
◦ The difference between replication,
transcription, and translation
◦ “Central Dogma”
◦ How DNA is packaged into a chromosome
Experiments:

Griffin
Hershey and
Chase
 Chargaff
 Meselson-Stahl

DNA Structure
Replication
Proofreading and repair

Mismatch Repair
◦ A DNA polymerase
does this as soon as
nucleotide is added
◦ other proteins do
this as well (they
continually monitor)

Excision Repair
◦ enzyme nuclease
cuts segment of strand
containing damage
◦ resulting gap is filled
(A DNA polymerase and
DNA ligase)
DNA packing
Chapter 17: From Gene to Protein

You Must Know
◦ The key terms gene expression, transcription,
and translation
◦ How to explain the process of transcription
◦ How eukaryotic cells modify RNA after
transcription
◦ The steps to translation
◦ How point mutations can change the amino
acid sequence of a protein
Translation
Chapter 18: Regulation of Gene
Expression

You Must Know
◦ The functions of the three parts of an operon
◦ The role of repressor genes in operons
◦ The impact of DNA methylation and histone
acetylation on gene expression
◦ The role of oncogenes, proto-oncogenes, and
tumor suppressor genes in cancer
Operons
Eukaryotic Gene Expression
Chapter 19:Viruses

You Must Know
◦ The components of a virus
◦ The differences between lytic and lysogenic
cycles
Structure
Capsid
 Envelope
 DNA or RNA

Replication
Information flow in cells can be regulated by various mechanisms.
(a) Describe the role of THREE of the following in the regulation of protein
synthesis:
RNA splicing
repressor proteins
methylation
siRNA
(b) Information flow can be altered by mutation. Describe THREE different
types of mutations and their effect on protein synthesis.
(c) Identify TWO environmental factors that increase the mutation rate in an
organism, and discuss their effect on the genome of the organism.
(d) Epigenetics is the study of heritable changes in the phenotype caused by
mechanisms other than changes in the DNA sequence. Describe ONE
example of epigenetic inheritance.
Chapter 20: DNA Technology and
Genomics

You Must Know
◦ The terminology of biotechnology
◦ The steps in gene cloning with special
attention to the biotechnology tools that
make cloning possible
◦ The key ideas that make PCR possible
◦ How gel electrophoresis
Terminology
Genetic Engineering
 Biotechnology
 Recombinant DNA
 Gene Cloning
 Restriction Enzymes
 Restriction sites
 Restriction fragments
 Sticky ends

Gene Cloning
PCR
Electrophoresis
4. The flow of genetic information from DNA to protein in
eukaryotic cells is called the central dogma of biology.
(a) Explain the role of each of the following in protein
synthesis in eukaryotic cells.
• RNA polymerase
• Spliceosomes (snRNPs)
• Codons
• Ribosomes
• tRNA
(b) Cells regulate both protein synthesis and protein activity.
Discuss TWO specific mechanisms of protein regulation in
eukaryotic cells.
(c) The central dogma does not apply to some viruses. Select
a specific virus or type of virus and explain how it
deviates from the central dogma.
Chapter 21

“Variation in molecular units provides
cells with a wider range of functions”
This chapter serves to connect genetics to
evolution.
 Illustrative examples listed for this
chapter are:

• Different types of hemoglobin
• MHC proteins
• Chlorophylls
• Molecular diversity of antibodies in response
to an antigen
Chapter 22: Descent with
Modification

You Must Know
◦ Natural selection is a major mechanism of evolution
◦ Biological evolution is supported by scientific
evidence from many disciplines, including math
◦ Graphical analysis of allele frequencies in a population
◦ Application of the Hardy-Weinberg equilibrium
equation
◦ Graphical analyses of allele frequencies in a
population
◦ Analysis of sequence data sets
◦ Analysis of phylogenetic trees
◦ Construction of phylogenetic trees based on
sequence data
Evidence for evolution



Direct observations
The fossil record
Homology
◦
◦
◦
◦
◦

Homologous structures vs. Analogous
Convergent evolution
Embryonic homologies
Vestigial organs
Molecular homologies
Biogeography
◦ Continental drift
◦ Endemic species
Chapter 23: The Evolution of
Populations

You Must Know
◦ How mutation and sexual reproduction each
produce genetic variation
◦ The conditions for Hardy-Weinberg
Equilibrium
◦ How to use the Hardy-Weinberg equation to
calculate allelic frequencies and to test
whether a population is evolving
Practice

Suppose in a plant population that red
flowers (R) are dominant to white flowers
(r). In a population of 500 individuals, 25%
show the recessive phenotype. How many
individuals would you expect to be
homozygous dominant and heterozygous
for this trait?
Some terms
Natural selection
 Genetic drift

◦ Founder effect
◦ Bottleneck effect
Gene flow
 Directional selection
 Disruptive selection
 Stabilizing selection
 Heterozygote advantage

Chapter 24: The Origin of Species

You Must Know
◦ The difference between microevolution and
macroevolution
◦ The biological concept of species
◦ Prezygotic and postzygotic barriers that maintain
reproductive isolation in natural populations
◦ How allopatric and sympatric speciation are
similar and different
◦ How an autopolyploid or an allopolyploid
chromosomal change can lead to sympatric
speciation
◦ How punctuated equilibrium and gradualism
describe two different tempos of speciation
Pre and Post Zygotic Isolation
Habitat
 Behavioral
 Temporal
 Mechanical
 Gametic
 Reduced Hybrid viability
 Reduced Hybrid fertility
 Hybrid Breakdown

Autopolyploid
Allopolyploid
Adaptive Radiation
3. Reproduction can be either asexual or sexual.
(a) Using a specific example, describe how organisms can
reproduce asexually. Discuss TWO evolutionary
advantages of asexual reproduction.
(b) Identify THREE ways that sexual reproduction increases
genetic variability. For each, explain how it increases genetic
diversity among the offspring.
(c) Discuss TWO prezygotic isolating mechanisms that prevent
hybridization between two species. Include in your discussion
an example of each mechanism.
4. Phylogeny reflects the evolutionary history of organisms.
(a) Discuss TWO mechanisms of speciation that lead to the development of
separate species from a common ancestor.
(b) Explain THREE methods that have been used to investigate the phylogeny of
organisms. Describe a strength or weakness of each method.
(c) The two phylogenetic trees represent the relationship of whales to six other
mammals. All of the organisms shown have a pulley-shaped astragalus bone in
the ankle except for the whale.
• For each tree, describe a monophyletic group, the closest relative to the
whale, and the point at which the pulley astragalus was lost or gained.
• Based on the principle of parsimony (the simplest explanation is the best)
and the genomic information in the table shown, identify which tree is the
best representation of the evolutionary relationship of these animals, and
justify your answer.
Chapter 25: The History of Life on
Earth

You Must Know
◦ The age of the Earth and when prokaryotic
and eukaryotic life emerged.
◦ Characteristics of the early planet and its
atmosphere
◦ How Miller and Urey tested the OparinHaldane hypothesis and what they learned
◦ Methods used to date fossils and rocks
◦ Evidence for endosymbiosis
◦ How continental drift can explain the current
distribution of species.
Chapter 26: Phylogeny and the Tree
of Life

You Must Know
◦ The taxonomic categories and how they
indicate relatedness
◦ How systematics is used to develop
phylogenetic trees
◦ The three domains of life including their
similarities and their differences
Phylogenies show evolutionary
relationships
3. Phylogeny is the evolutionary history of a species.
(a) The evolution of a species is dependent on changes in the genome of the
species. Identify TWO mechanisms of genetic change, and explain how each
affects genetic variation.
(b) Based on the data in the table below, draw a phylogenetic tree that reflects the
evolutionary relationships of the organisms based on the differences in their
cytochrome c amino-acid sequences and explain the relationships of the
organisms. Based on the data, identify which organism is most closely related
to the chicken and explain your choice.
(c) Describe TWO types of evidence—other than the comparison of proteins
—that can be used to determine the phylogeny of organisms. Discuss one
strength of each type of evidence you described.
Three Domains
Characteristic
Bacteria
Archaea
Eukarya
Nuclear Envelop
No
No
Yes
Membrane-enclosed
organelles
No
No
Yes
Introns
No
Yes
Yes
Histone proteins assoc. with
DNA
Circular chromosome
No
Yes
Yes
Yes
Yes
No
Chapter 27: Bacteria

You Must Know:
◦ Electrophoresis
◦ Plasmid-based transformation
◦ Restriction enzyme analysis of DNA