Chapter 21: Viruses
1. What is a virus? Name and describe its component parts.
2. How are viruses like and unlike prokaryotic and eukaryotic life?
3. Do viruses evolve? Do they share a single evolutionary origin?
4. Name and describe three competing (but not mutually exclusive) hypotheses about the origins of
viruses.
5. Why does a virus need a host? What types of organisms tend to be frequently infected by viruses?
6. Distinguish between DNA viruses and RNA viruses, and name four examples of each.
7. Summarize how humans (individually and medically) fight viruses.
8. Explain how virus evolution results in emergent diseases (or spillover events) such as the COVID-19
pandemic.
9. Briefly explain how new medical technologies are using viruses to fight cancer, bacterial superbugs,
and hereditary disorders.
Chapter 22: Prokaryotes
1. What is a biofilm, how does it develop, and how does it make life easier for its members? What is a
stromatolite? And what do they have in common with each other? How old are the oldest prokaryotes
(that we know about)?
2. What is a microbiome? In what ways do you depend on one?
3. Describe the various nutritional modes of prokaryotes. Which nutritional mode would you expect to find
in the vicinity of a hydrothermal vent?
4. What is an extremophile? Give several examples of places you might find one.
5. Describe the "base" of the tree of life. Which prokaryotes are older: archaea or bacteria?
6. Name the three basic shapes of bacterial cells, and give an example of a bacterial species of each
shape.
7. What is peptidoglycan, and what does it have to do with the results of a gram stain procedure?
8. Name several mechanisms by which bacteria maintain or increase their genetic diversity.
9. Explain several important ecological roles of prokaryotes.
10. Give examples of bacterial pathogens that have affected human societies.
11. Do you understand how and why antibiotic resistance evolves in a "superbug" bacterium?
12. How are prokaryotes used in bioremediation?
Chapter 23: Protists
Explain endosymbiotic theory, and identify the evolutionary ancestors of mitochondria and plastids (such
as chloroplasts).
2. What is a protist?
3. Do protists form a clade?
4. What is special about the eukaryote supergroups called "Archaeplastida" and "Opisthokonta"?
5. How do protists acquire their nutrition? Identify examples.
6. How big is a protist? Identify examples.
7. How are protists ecologically important?
8. How are protists economically important?
9. What does the word "algae" mean? Name and describe at least six different types of algae.
10. How is "phytoplankton" different from "algae"? Name some examples of phytoplankton.
11. What does the word "protozoan" mean? Name and describe at least six examples.
12. Name and describe at least four parasitic protozoans that can infect humans.
13. Name a protist with a support structure made of each substance: cellulose, calcium carbonate, silica.
14. What does the word "mold" mean? Name at least three types of mold that are NOT members of the
fungus clade.
Chapter 24: Fungi
1. What are the shared derived characters of the fungus clade? How do fungi acquire nutrition, and what
implications does this have for their diet and consequent ecological roles?
2. Are all fungi multicellular? How big is a fungus? Identify examples on either end of the spectrum.
3. Describe the basic anatomy of a fungus, using appropriate vocabulary to describe the individual
filaments, a mass of filaments, and the composition of the cell walls.
4. Describe the life cycle of a typical multicellular fungus. Use appropriate vocabulary, especially
regarding the features that are unique to the fungus life cycle. Does a fungus spend most of its life
haploid or diploid? Give examples of sexual and asexual reproduction among fungi.
5. Can you explain the terms mycorrhizae and mycosis, and give examples of each?
6. Describe examples of fungi that are mutualists with plants, mutualists with animals, mutualists with
algae or cyanobacteria, parasites on plants, parasites on animals, and saprobic "decomposers."
7. What is a lichen, and how do its parts work together?
8. How are fungi economically important?
Chapter 25: Plants
1. Describe a few of the closest cousins of land plants, and what shared derived characters they have in
common.
2. Imagine you are among the first embryophyte land plants to emerge from the aquatic
environment. What aspects of your life would be easier on land, and what new challenges would shape
your future adaptations?
3. Define and describe the life cycle known as "alternation of generations." Which life stages are haploid,
and which are diploid?
4. All land plants have a sporophyte generation and a gametophyte generation. But the relative size and
shape of each one has changed over the course of plant evolutionary history. Explain this trend, and
compare / contrast the life cycle of a bryophyte to the life cycle of a fern.
5. Name the three major clades of nonvascular plants (i.e., bryophytes). Identify some habitat restrictions
that these plants have, based on their anatomy, compared to other kinds of plants that evolved more
recently.
6. Name the two major clades of seedless vascular plants and identify a few examples of each.
7. What are spores, and how are they dispersed in 1) nonvascular plants and 2) seedless vascular plants.
8. How are sperm dispersed in 1) nonvascular plants and 2) seedless vascular plants? What implications
does this have for their habitat requirements?
9. Describe the economic importance of ancient (i.e. Carboniferous) forests made up of tree-like seedless
vascular plants and early gymnosperms.
Chapter 26: Plants
1. What exactly is a seed? How is it different from, say, a spore or a gamete?
2. What are the shared derived characters of seed plants, and what kinds of ecological advantages
(and new habitat opportunities) are associated with those adaptations?
3. Characterize the sporophyte and gametophyte generations of a seed plant.
4. Identify the shared derived characters of the gymnosperm clade, and characterize the function of
two different cone types.
5. List at least four types of gymnosperms, and name the most diverse gymnosperm clade.
6. Discuss the evolutionary advantages of an adaptation called pollen. What exactly is pollen, and
how is it generally dispersed in gymnosperms and angiosperms?
7. What are the shared derived characters of angiosperms, and what kinds of ecological advantages
are associated with those adaptations? (i.e., Why do angiosperms "rule the plant world" in terms of
abundance and diversity?)
8. What exactly is a flower, and how does it work?
9. What exactly is a fruit? If you have not yet sorted this out in your notes, what is the difference
between an ovule and an ovary?
10. Name some ways in which different types of angiosperms deal with the challenge of seed
dispersal.
11. List a few typical differences between the monocot and eudicot clades.
Chapter 27: Animal Diversity
1. What is a "body plan" and what are some very general categories for animal body plans?
Body plan refers to the morphology of an animal determined by developmental cues.
2. Describe the early stages of embryonic development (i.e., that all animals have in common),
from a zygote through the step called gastrulation.
Zygote processes through primary germ layers (ectoderm, endoderm, and mesoderm) reorganized to
form embryo. Tissues specialize the organs and organ systems to determine future morphology and
physiology.
- Cleavage, the beginning, mitotic cell division of zygote without cell growth resulting in blastomeres.
There are three cell divisions that result in 8 celled structure. Solid molura formed. Followed my blastula.
Gastrulation happens last resulting in the development of the primitive gut (digestive cavity) and
embryonic germ layers that will later be mapped for certain functions.
3. What are Hox genes, which animals have them (and which do not), and why have scientists
concluded they played an important role in evolutionary history?
Homeotic genes that contain DNA sequences called homeoboxes and encode for protein transcription
factors. Hox genes are a cluster of genes responsible for determining general body plan (appendages,
number and placement, and head to tail directionality).
It is believed that hox genes have undergone 2-4 duplications during animal evolution that accounts for
complex body types to evolve.
Two of the five clades of animal kingdom do not have hox genes: Ctenphora (comb jellies) and Porifera
(sponges)
4. Name some animal clades that are "diploblastic." What are the names of their germ
layers? What type of symmetry do they have?
Cnidaria (sea anemones, corals, jelly fish, etc.) are diploblastic. During gastrulation when the germ layers
are being developed, only two defined layers form, the ectoderm, and the endoderm with an absent
middle layer. Animals that have radial, bi-radial, or rotational symmetry develop two germ layers.
5. Name some animal clades that are "triploblastic." What are the names of their germ
layers? What type of symmetry do they have?
More complex animals tend to develop three layers. Endoderm, mesoderm, and ectoderm. These are
more complex animals that tend to have bilateral symmetry.
Endoderm: turns into digestive tract and respiratory tract.
Mesoderm: All muscle tissues
Ectoderm: All epithelial coverings of the outer body.
6. What is a coelom, what is it for? Which animal clades have coelom, and which do not?
Coelom is a body cavity that derives from triptoblasts from the mesoderm layer. It is epithelial lines,
usually filled with fluid and lies between the visceral organs and the body walls acting as a cushions,
shock absorber and encloses the major organs while allowing freedom to grow and move. Also provides
space for diffusion of gases and nutrients.
True coelems: Annelids (earthworms), mollusks (oysters, clams, slugs), arthropods(crustaceans, insects),
echinoderms (star fish). chordates.
Those that do not have coelems: Acoelomates. Ex: flatworms
7. What is a "pseudocoelomate"? Which animal clades fit this description?
Psuedocoelomates are a third subset of triptoblasts that have a coelem partly lines by mesoderm and
endoderm and are considered a “false coelom”.
Ex: roundworms.
The differentiation is best determined during embryological development.
9. What do the names "protostome" and "deuterostome" literally mean (i.e., their Greek
translation), and what aspect of embryonic development corresponds with these names?
Protostome: Mouth first. The mouth of the animal of triploblastic eucoelomates develops at the blastopore
site. Ex: Arthropods, mollusks, and annelids.
Deuterostome: Mouth second (anus first). The anus of the animal of triploblastic eucoelomates develops
at the blastopore site.
Ex: Chordates (human, tigers), echinoderms (starfish)
11. The protostome clade can be further divided into two major groups. Name these, and explain
the shared derive character that best defines each clade.
Ecdysozoa--> Nematodes (round worms) and arthropods (star fish)
Lophotrochozoa -->Phoronids. Tentacles.
12. Your textbook refers to "a time of impressively rapid animal evolution and diversification of
body forms." By what name is that adaptive radiation generally known?
Cambraian explosion.
13. How many mass extinction events are evident in the geological record? Name and briefly
describe two of these, and indicate how long ago they happened: 1) the most recent mass
extinction and 2) the largest mass extinction.
There are five mass extinctions evident in the geological record.
End-Permian is the largest mass extinction on record, desicrating over 95% of extant species. Caused a
warm and stable climate for diversification of dinosaur species and plant species to radiate land and
water.
End-Cretaceous is another mass extinction that wiped out the dinosaurs. The most recent mass
extinction.
Chapter 28: Chordates
1. What is a ctenophore? Why is this clade mysterious and somewhat difficult to pin down on the
animal phylogeny?
Basal clade of the animal kingdom. They are comb jellies that are considered sister group of Cnidaria and
the sponges (porifera). Presence of nerve and muscle cells present. No hox genes or neural development
as seen in other animals.
Data and analytical methods play a role in developing phylogenies making analysis and reanalysis
incomplete so a former tree cannot be fully disproved.
2. Describe the shared derived characters of the phylum Porifera. Why are they considered animals, and
why are they considered basal among animal phyla? How do they eat, reproduce, and support
themselves? Do they move? (If so, how?) Do they have symmetry (if so, what type?), true tissues (if so,
how many germ layers)?
3. Describe the shared derived characters of the phylum Cnidaria (hint: name the structures they use to
kill prey). Why are they considered animals, and why are they considered basal among animal
phyla? How do they eat, reproduce, and support themselves? Do they move? (If so, how?) Do they
have symmetry (if so, what type?), true tissues (if so, how many germ layers)? Do they have a head
and/or a brain? (If not, what do they use instead?) Name and describe the two life stages in the typical
cnidarian life cycle. Do all cnidarians have both life stages? If not, which one may be missing? Name
some examples of major cnidarian clades. What are some special features that make corals unique?
4. We learned (briefly) in the previous chapter, about a huge group of protostomes that do not have
exoskeletons (although some do have hard parts). Name the clade that is characterized by an ancestral
ciliated feeding apparatus (still present in the the larval life stage of many members). This clade includes
flatworms, ribbon worms, rotifers, annelids, mollusks, brachiopods and ectoprocts.
5. What is the informal name for the phylum Platyhelminthes? Do they have symmetry (if so, what
type?), true tissues (if so, how many germ layers)? Do they have a body cavity? Do they have a head
and/or a brain? (If not, what do they use instead?) Name at least one member of this clade that are freeliving, and a few that are parasitic.
6. Describe the general features of a typical member of the phylum Rotifera, including their size, shape,
and general habitat. Do they have symmetry (if so, what type?), true tissues (if so, how many germ
layers)? Do they have a body cavity (if so, is it a coelom or a pseudocoelom?) Do they have a head
and/or a brain? (If not, what do they use instead?) Certain rotifers are famous for having many
generations of parthenogenic reproduction. What does that mean?
7. Describe the general features of a typical member of the phylum Mollusca. While they might not
always look that way, mollusks are bilaterally symmetrical and of course, triploblastic. They even exhibit
segmentation (repetition of body parts, as seen in the chiton) although it is not always obvious because
their body segments have become specialized in various ways. Do they have a body cavity? (if so, is it a
coelom or a pseudocoelom?) Do they have a head and/or a brain? Name and briefly describe three
major clades of mollusks (not including chitons).
8. What is the Latin name of the segmented worm phylum? Do these triploblastic bilaterians have a body
cavity? (if so, is it a coelom or a pseudocoelom?) Name and briefly describe three major clades.
9. We learned (briefly) in the previous chapter, about a group of protostomes called Ecdysozoans
characterized by having (and needing to shed) an exoskeleton or cuticle made of the polysaccharide
chitin, and occasionally reinforced with stronger material such as calcium carbonate. Name three phyla
that belong to this clade.
10. What is the Latin name of the roundworm phylum? Do these triploblastic bilaterians have a body
cavity? (if so, is it a coelom or a pseudocoelom?) Do they exhibit cephalization? How about
segmentation? Name at least one member of this clade that are free-living, and a few that are parasitic.
11. Briefly describe the curious creatures called Tardigrades, and indicate which (more familiar) phylum is
their "sister" group.
12. What is the Greek name of the most diverse animal phylum, and what does it mean in
English? Describe the shared derived characters of this phylum, and name the four major clades.
13. Briefly describe each of the major arthropod clades, and give several examples of each. Where do
the ancient armored animals called horseshoe crabs fit in? How about the pill bugs or "roly polies"?
14. We will learn about our own phylum, the chordates, in the next chapter and module. But chordates
are NOT the only deuterostomes. Describe the three major clades that make up the phylum
Echinodermata, and indicate what major adaptations they have in common with each other. Finally,
describe the ecological role of each major clade (i.e., based on its diet).
Chapter 29: Chordates
1. Describe the shared derived characters of primates, and name the major primate clades.
2. What exactly does the word hominid mean (to a biologist, NOT to an anthropologist or a
reporter). Describe the shared derived characters of hominids. Discuss the evolutionary history of the
hominin clade. Name and describe at least two hominin genera apart from Homo. Name and describe at
least two other humans (i.e., members of the genus Homo) apart from Homo sapiens.
Evolution of Skin color vid:
1. Identify the significance of melanin, pheomelanin, eumelanin, Vitamin D, and folate in the context
of modern human evolution.
2. Explain the selective advantages of dark skin and light skin in the different habitats where they
evolved
Evolution of Lactose vid:
1. Distinguish between the role of lactose and lactase in this story. Is it rare or common for adult
mammals to be able to digest milk? Explain your answer.
2. Is there a genetic basis for lactase persistence in humans? Explain your answer.
3. When and where did lactase persistence evolve in modern humans? Did it happen once or more than
once?
4. Name a part of the world with a high proportion of adults who are lactase persistent.
5. Name a part of the world with a low proportion of adults who are lactase persistent.