Biology 160
Reading Guide 14: Ecosystems, Part II
NAME: _______________________________________
This is DUE: ________________
Come prepared to share your findings with your group.
This is a long reading guide, but most of it is skimming. Pay special attention to the information needed
to answer Critical Thinking questions.
*As before, please turn in only the Critical Thinking questions on a separate sheet of paper.
Critical Thinking questions: 43, 50, 55, 57, 63, 88, 93, 108
** Fill this reading guide out as you are reading the chapters. This will help you to pull out the important
information that will help us to understand how an ecosystem reacts to change and how matter and energy flow
within and through it, respectively.
In this reading guide you’ll learn about:
 The diversity of life on Earth and how they are related
 How matter and energy flows through an ecosystem
Readings:  Essential Biology, 4th or 5th Ed. (Simon, Reece, & Dickey)
Ch 15, pg 293-295; 305-311
Skim
Ch 16, pg 315-327; 329-332
Ch 17, all
Ch 20, pg 425-443
Ch 18, pg 394-399
While reading these chapters, constantly ask yourself, “How is this information helping me to understand
how matter and energy flow through an ecosystem?”
Ch 15, pg 293-295; 305-311
Major Episodes in the History of Life
1. How old is Earth?
2. When did its crust begin to solidify?
3. When did life appear on Earth?
4. What type of organisms were Earth’s earliest life forms?
5. When did the oxygen revolution begin?
6. How did species adapt to this increase of oxygen in the atmosphere?
7. Think Back: Chapter 6, pg 103
a) Where does the oxygen we breathe come from?
b) What is the evidence that glycolysis is an evolutionarily ancient process?
8. When did eukaryotes appear?
9. Once multicellularity evolved, much more complex organisms could emerge. When did the first
multicellular organisms appear?
10. When was the greatest diversification of animals and what was this period called?
11. What percentage of biological history was life confined to the water?
12. Which organisms first colonized land and when?
13. What did plants do to support the evolution of land animals?
14. Make sure that you can answer the Checkpoint questions. If not, write your questions here:
15. Think Back: What types of bacteria and archea are found today?
The Ecological Impact of Prokaryotes
16. Give some examples of how prokaryotes do what life depends on.
17. What is bioremediation?
Protists and The Origin of Eukaryotic Cells
18. How did eukaryotic cells evolve?
19. Explain the endosymbiosis model of the evolution of eukaryotic cells and the evidence that supports it.
20. What types of protists are found today?
Ch 16, pg 315-327; 329-332
Colonizing Land
21. What is a plant?
22. What distinguishes plants from algae?
23. Redraw Figure 16.1 to help you understand the link between the environment and adaptations between algae
and plants. Know and understand these structural adaptations.
24. What are mycorrhizae and what do the fungi and plants do for each other?
25. Did you know before reading this that most plants have mycorrhizae?
YES or NO
26. What is lignin and what does it do for a plant?
27. What are the two types of vascular tissue of plants and what do they do?
a)
b)
28. Describe the reproductive adaptations that plants have for living in a drier environment.
29. Describe the story of how plants may have developed from an early ancestor of charophytes by natural
selection.
30. Make sure that you can answer the Checkpoint questions. If not, write your questions here:
31. Remember the order of plant diversification! For each of the following describe the environments that they
are adapted to and an example of each:
a) bryophytes
b) seedless vascular plants
c) gymnosperms
d) angiosperms
The Ecological Impact of Fungi
32. Think back: What are fungi?
33. Describe the role of fungi as decomposers in an ecosystem:
34. What is parasitism?
35. About what percentage of known species of fungi are parasitic? Give a few examples.
36. Think Back: Remind yourself of some of the commercial uses of fungi.
37. Compare and contrast: symbiosis, parasitism, and mutualism.
38. What are lichens?
Ch 17, all – skim through this chapter to get a feel for all of the different animal body plans that have
evolved.
39. What is an animal?
40. What happened during the Cambrian explosion?
41. Are scientists in agreement of why the Cambrian Explosion happened? YES or NO
Give an example of a current hypothesis:
42. Figure 17.6 shows a phylogenetic tree of all the major animal phyla categorized by body plans (and
modified with recent genetic data) that exist in animals today and that were generated during the Cambrian
explosion. Using the descriptions in the text, list out the major body plan characteristics of each of the phyla
and give an example of each:
Phylum
Sponges
Cnidarians
Major Body Plan Characteristics
Invertebrates; No true tissues
Invertebrates; True tissues; radial symmetry; gastrovascular cavity;
polyp or medusa
Molluscs
Invertebrates;…
Flatworms
Invertebrates;…
Annelids
Invertebrates;…
Roundworms Invertebrates;…
Arthropods
Invertebrates;…
Echinoderms
Invertebrates;…
Chordates
Includes Invertebrates and Vertebrates;…
Example of a
specific animal
Sponge
Jellyfish or hydra or
coral or sea
anemone
43. Critical Thinking: What things do humans have in common with
a) invertebrate animals?
b) plants, fungi, and protists?
c) bacteria?
**Hint: work your way down to the cellular level….
44. What are the major characteristics of vertebrates?
45. As you can see from Figure 17.29, vertebrates are a subcategory of chordates. Let’s take a look at the major
body plan characteristics of vertebrates now as we work our way towards humans….
Vertebrate Class
Major Body Plan Characteristics
Example of a
specific animal
Lampreys
Cartilaginous fishes
Bony fishes
Amphibians
Reptiles
Mammals
Now that eutherian (or placental) mammals have evolved in the history of life on Earth, let’s trace the evolution
of humans (which are also eutherians) from our mammalian primate ancestors…
The Human Ancestry
46. What are the characteristics of tree-dwelling primates?
47. What are the hominoids?
48. For how long have humans and chimpanzees shared a common ancestry?
49. What is paleoanthropology?
50. Critical Thinking Checkpoint:
Discuss some of the common misconceptions about human evolution:
a) Are humans directly related to chimpanzees?
Why?
b) Is human evolution like a ladder?
Why?
YES or NO
YES or NO
c) Did upright posture and an enlarged brain evolve simultaneously? YES or NO
Why?
51. Who was Lucy?
52. Describe Homo habilis.
53. Describe Homo erectus.
54. Describe Homo neanderthalensis.
55. Critical Thinking: Homo sapiens appear to have once interbred with Homo neanderthalensis (!)
According to the biological species concept, what implications does this have in calling Homo
neanderthalensis a different species? (Check out this link for more info!
http://www.sciencefriday.com/segment/05/07/2010/neanderthal-genome.html)
56. Where and when do the oldest known fossils of Homo sapiens, our own species, come from?
57. Critical Thinking: So could humans and dinosaurs have coexisted? Why? (Make sure you use Table
14.1 on pg 281 as your evidence).
58. Describe some of the evidence that suggests that all living humans have ancestors that originated as Homo
sapiens in Africa.
Ch 20, pg 425-443
Now that we’ve learned about the different environments that have led to the evolution of the amazing diversity
of life on our planet through descent with modification or evolution, let’s look now at how all of these species
interact with one another in a community. We will also gain knowledge for understanding the flow of matter
and energy through an ecosystem.
59. What is biodiversity?
60. According to the text, why does biodiversity matter?
61. Describe the 3 types of biodiversity:
a) genetic diversity
b) species diversity
c) ecosystem diversity
62. Describe the 4 main factors responsible for the current loss of biodiversity:
a) habitat destruction
b) invasive species
c) overexploitation
d) pollution
63. Critical Thinking: On the topic of biodiversity, think about a current event that you have heard of or
about something that you have read in this chapter so far and write down a question that you have about
it.
64. What is a community?
65. Describe the five key interspecific interactions in a community:
a) Interspecific competition
b) Mutualism
c) Predation
d) Herbivory
e) Parasites and Pathogens
66. Make sure that you can answer the Checkpoint questions. If not, write your questions here:
67. What is a trophic structure?
68. What is a food chain? Make sure that you understand the arrow directions in Figure 20.15.
69. What are producers, consumers, and decomposers? Give some examples.
70. What are herbivores, carnivores, and dentrivores? Match these up with producers, consumers, and
decomposers.
71. What is biological magnification? (Note: for those of you who eat fish, this is also the reason for the need to
stay away from certain fish like tuna and swordfish due to high levels of mercury found in them).
72. What is a food web?
73. Explain the impact of species diversity of plants on the species diversity of animals in the same community.
74. What is a keystone species?
75. What happens when a keystone predator is eliminated from a community?
76. What are community disturbances? List some of the positive and negative impacts of disturbances.
77. What is ecological succession?
78. Compare and contrast primary succession with secondary succession.
79. Interested in the after-effects of a large-scale disturbance like the eruption of Mount St. Helens? Check out
the following website: http://www.fs.fed.us/gpnf/mshnvm/education/teachers-corner/library/life-returns.shtml
80. What is an ecosystem?
81. Redraw Figure 20.25 to help you remember the two major ecosystem processes: energy flow and chemical
cycling.
82. Describe how energy flows through an ecosystem:
83. Describe how chemicals cycle within an ecosystem:
84. What is the key distinction between energy flow and chemical cycling?
Energy Flow in Ecosystems
85. What is biomass?
86. What is primary production?
87. What “sets the spending limit for the energy budget of the entire ecosystem”?
88. Critical Thinking: Can an ecosystem use more energy than is stored by its producers? Why?
89. Redraw Figure 20.27 to help you to understand how the energy in a food source is used by its consumer.
90. What is a pyramid of production?
91. Redraw Figure 20.28 to help you to remember that only ~10% of the energy from each trophic level can be
used by each successive trophic level and converted to new biomass (growth).
92. What limits the length of food chains?
93. Critical Thinking: If you were stuck on a desert island with only some corn and some egg-laying
chickens to eat (Many apologies to the vegetarians! Think of this as a brain exercise only), how would
you plan your meals to get the most energy from your food?
94. Make sure that you can answer the Checkpoint questions. If not, write your questions here:
95. What is a biogeochemical cycle?
96. Take a look at each cycle in Figures 20.32, 20.33, 20.34, and the water cycle in Figure 18.38. Redraw the
carbon cycle here to help you remember how this important chemical cycles within an ecosystem.
97. Explain how a “dead zone” can result from nutrient pollution.
Ch 18, pg 394-399
Global Climate Change
98. What is the Intergovernmental Panel on Climate Change (IPCC)? To learn more about them you can visit
their website at : http://www.ipcc.ch/.
99. What are some greenhouse gases?
100. What is the greenhouse effect?
101. What has been the rise of CO2 levels since the late 1700’s and where has most of this CO2 come from?
102. What is the effect of the increase of greenhouse gases on global temperature?
103. What is the effect of the increase of greenhouse gases on the oceans and the marine communities within?
104. Explain some of the effects of climate change on species distribution.
105. Explain some of the effects of climate change on ecosystems.
106. What is your carbon footprint and what can you do to reduce it? Here some places to check:
Seattle Climate Action NOW
http://seattle.co2challenge.com/index.php
The Nature Conservancy
http://www.nature.org/initiatives/climatechange/calculator/?gclid=COau-O7E1KUCFQULbAodo06rmA
Environmental Protection Agency
http://www.epa.gov/climatechange/emissions/ind_calculator.html
CoolClimateNetwork (a partnership with the University of California at Berkeley)
http://coolclimate.berkeley.edu/
Center for Sustainable Economy (many people in the class chose this site to look at)
http://www.myfootprint.org/
107. Explain the effect of climate change as an agent of natural selection.
108. Critical Thinking: Think about all that you have learned in this reading guide: biodiversity, species
interactions, trophic structure, energy flow and chemical cycling. How do you think climate change will
effect humans? You in particular? Yours or a friend’s children and grandchildren?
If you want to learn even more, check out NSCC’s Environmental Studies classes!
Wow. No more reading guides. Congratulations for a job well done!!