Ch.2 - Food

environmental biology lecture

Reading Assignment

Chapter 2: Food -- click on this link to download.

Video Assignment

TED Talk: Jill Farrant: How we can make crops survive without water.

As the world's population grows and the effects of climate change come into sharper relief, we'll have to feed more people using less arable land. Molecular biologist Jill Farrant studies a rare phenomenon that may help: "resurrection plants" — super-resilient plants that seemingly come back from the dead. Could they hold promise for growing food in our coming hotter, drier world?

TED Talk: Louie Schwartzberg: The hidden beauty of pollination

Pollination: it's vital to life on Earth, but largely unseen by the human eye. Filmmaker Louie Schwartzberg shows us the intricate world of pollen and pollinators with gorgeous high-speed images from his film "Wings of Life," inspired by the vanishing of one of nature's primary pollinators, the honeybee.

Note Card Assignment

Prepare a single, personally-prepared, 3-inch x 5-inch note card.

Your note card may be used during the exam. Submit it for credit when turning in exam form. (one point).

Study Questions

Recommendation (NOT an assignment): Print these study questions. Then as you move through the reading or video, jot down short answers. Keep your answers VERY short, a few key words or phrases to prompt your memory. Remember, this activity is a study aid to help you prepare for the exam. Do what you need to do, but don't overdo it. You are NOT submitting your answers for points.

Reading assignment study questions

  1. Why is a rock not food? Or a Cessna 150?
  2. So, exactly what IS food?
  3. Plants and photosynthetic plankton produce chains of carbon. Where does the carbon come from?
  4. What is the first trick in making food, and what is the biochemical operation that does it?
  5. What is the general reaction equation for photosynthesis?
  6. Photosynthesis consumes three different environmental resources. What are they and where does the plant get them from?
  7. What good are sugar molecules?
  8. Why do starchy foods such as bread, rice, and potatoes taste so good?
  9. What are two examples of polymers made out of glucose?
  10. What is cellulose, and how do plants put it to use?
  11. Why does wood burn?
  12. If wood is made from glucose, why don’t we eat the wood as food?
  13. How does biosynthesis make an amino acid out of a short carbon chain?
  14. How do plants get the nitrogen to make amino acids?
  15. What is a salt?
  16. What makes a salt a “mineral nutrient?”
  17. From the diagram on “Biosynthetic Pathways in Plants.” What kinds of biological molecules does biosynthesis make out of fixed carbon chains and salts of nitrogen, phosphorous, sulfur, magnesium and potassium?
  18. What form of energy is the “ultimate source of all energetic expressions by living things?”
  19. What kinds of biological molecules are particularly good at storing chemical energy?
  20. What is the general reaction equation for cellular respiration?
  21. What is happening to the biological molecules being operated on in cellular respiration?
  22. Cellular respiration produces a molecule called ATP. What is useful about this molecule?
  23. How do cells get rid of the pile of hydrogen atoms that accumulate as a result of cellular respiration?
  24. You are breathing in O2. What is the ultimate job you have for O2 once it enters your cells?
  25. What are examples of consequences for plants and animals should they not be able to replenish internal food reserves?
  26. Define autotrophic. Give examples of autotrophs.
  27. Define heterotrophic. Give examples of heterotrophs.
  28. What are the two main branching exchange systems in plants? What resources do each of these systems collect from the environment?
  29. If the non-photosynthetic cells in a plant can’t make their own food, how do they acquire it?
  30. If the photosynthetic cells in the leaves cannot collect their own water and nutrients, how do they acquire them?
  31. To the extent that roots collect water and mineral nutrients…
  32. To the extent that photosynthesis proceeds in the leaves…
  33. Tropical rain forest. Sounds like a great place for plants. But it’s a hard life. Why?
  34. What are the two advantages for a tree in the tropical rain forest when it grows tall and spreads out its leaves like a big umbrella?
  35. What are the advantages of large surface roots and buttressed roots in the tropical rain forest?
  36. What are stomata? How do they affect rates of photosynthesis in the plant?
  37. How do stomata affect the rate of water loss in the plant?
  38. When operating stomata, what two operations must the plant balance?
  39. How does the little bromeliad plant persist in an environment dominated by gigantic trees?
  40. In the tropical rain forest, trees became dominant by maximizing their exposure to the sun. Why does this approach reduce persistence in arid environments?
  41. For plants living in hot and arid environments, what is the result of reduced heat uptake from the sun?
  42. How do plants in hot, arid environments reduce heat uptake from the sun?
  43. Many plants in hot and arid environments express some form of vertical orientation. What’s “up” with that?
  44. Basic differences between plants and animals are…?
  45. Define herbivore and give examples.
  46. In terms of the plant’s reproductive system, what is a flower?
  47. In terms of the plant’s reproductive system, what is an apple?
  48. Animals eat flowers, fruits and nuts. Expensive for the plants. How does providing free food for animals increase persistence of these generous plant species in the area?
  49. How do carrots, potatoes and beets manage their surplus food supply, and how do animals exploit the results?
  50. In many kinds of environments, grass is plentiful and some kinds of animals eat it. Why?
  51. Leaf cutter ants can’t digest the cellulose in the leaves they collect. So, how do they get nutrition out of leaves?
  52. Termites do not produce cellulase (an enzyme that splits cellulose into individual glucose molecules). Yet termites derive abundant nutrition from the wood that they eat. How does this process work and wht kinds of organisms are involved?
  53. In terms of the plant’s reproductive system, what is pollen?
  54. How do animals come to acquire carotenoids?
  55. How does giving carotenoids to animals increase persistence in flowering plants?
  56. Seeds are very rich in an easy-to-digest polymer of glucose. What is the name of this polymer?
  57. The gizzard in birds is useful in doing WHAT to seeds?
  58. How do ruminating herbivores go about digesting the large amounts of grass and leaves that they ingest?
  59. What is a cow doing when she is “chewing her cud”?
  60. Strict herbivorous mammals have distinctive jaws and two main kinds of teeth. What are they and where are they?
  61. What is the interesting, and slightly disgusting, method that rabbits use to acquire the maximum amount of nutrition from the grass they eat?
  62. For strict herbivores, acquiring food is easy, but_____ food is hard.
  63. For strict carnivores, digesting food is easy, but ______ food is hard.
  64. Since spiders have no teeth, how do they get nutrition from the animals they kill?
  65. Give a couple of examples of carnivorous insects.
  66. In terms of mouth parts, how are insects different from spiders?
  67. What is the favored technique used by most reptiles in capturing prey?
  68. What are the main applications of reptilian teeth?
  69. Why do reptiles tend to swallow their prey whole?
  70. Bird carnivores express high diversity in anatomy, diet and hunting techniques. Give some examples of raptors.
  71. What technique of food management stands out regarding the shrike?
  72. What kinds of mammals are strict carnivores?
  73. Why is the cat’s snout so short?
  74. Describe the two main kinds of teeth in the cat jaw, and how are they used to process food?
  75. What is an omnivore? Give examples.
  76. Omnivory is accompanied by a) a much reduced behavioral repertoire; or b) a very flexible behavioral repertoire?
  77. What kinds of food do omnivores eat?
  78. How does an omnivorous diet affect an animal’s persistence as compared to being a strict carnivore?
  79. Compare the anatomies and tooth configurations of the dog’s skull, the cat’s skull and the deer’s skull. Relate differences to diet.
  80. Is the tooth configuration of humans more similar to mammals that are strict herbivores, strict carnivores, or omnivores?
  81. What are examples of decomposers?
  82. How are fungi a little bit like plants and a little bit like animals?
  83. Our bodies are covered with decomposers. What are they “trying” to do to us?
  84. Ecologically, what important operations do decomposers do in natural environments?
  85. How is a food web different from a food chain?
  86. Be able to draw a simple food web.
  87. Considering a food web, what might happen if all the carnivores and omnivores were removed?
  88. Considering a food web, what might happen if a super herbivore was introduced?
  89. Considering a food web, what environmental circumstances constrain plants?
  90. Considering a food web, what environmental circumstances consumers?
  91. How does the complexity of a food web influence its robustness?
  92. What is a trophic level?
  93. As the food energy from one trophic level is transferred to the next higher level, what proportion of the original actually gets transferred?
  94. If the plants of an ecosystem contained 500,000 calories of energy, how much of that energy could be transferred to carnivores in the third trophic level of that system?
  95. How does this energetic relationship explain the abundance or rarity of producers and top carnivores?
  96. Where do decomposers fit in this food pyramid?
  97. Predict what would happen to an ecosystem if all the decomposers suddenly and permamnently disappeared.
  98. For a given ecosystem, there are only two top carnivores. Predict what would happen to the population of top carnivores if half of the plants in the ecosystem were destroyed to make room for a shopping mall.
  99. Grasses produce what toxic chemical – that can act as a deterrent to grazing animals?
  100. Why should you not make a salad out of the leaves of potato plants?
  101. Where is the living layer of cells in a tree trunk? What anatomical structure protects these cells?
  102. Why does the monarch butterfly taste so bad to predators?
  103. Why would you not disturb stink beetles, skunks, or porcupines?
  104. How does group awareness help organisms from becoming food? Give examples.
  105. How does being large help organisms from becoming food? Give examples.
  106. How does herding behavior help organisms from becoming food? Give examples.
  107. How does warning coloration help organisms from becoming food? Give examples.
  108. How do warning sounds help organisms from becoming food? Give examples.
  109. How does bluffing behavior help organisms from becoming food? Give examples.
  110. How does camouflage help organisms from becoming food? Give examples.
  111. How does a briar patch lifestyle help organisms from becoming food? Give examples.
  112. How does the use of safe havens help organisms from becoming food? Give examples.


Video assignment study questions

TED Talk: Jill Farrant: How we can make crops survive without water.

  1. What are the two main global developments driving efforts to produce more drought-tolerant crops?
  2. How do "annual" plant species avoid the harmful effects of drought?
  3. What are resurrectioun plants?
  4. What are "promoters" in the context of genetics?
  5. What genetic trick do resurrection plants use to survive extended drought?

TED Talk: Louie Schwartzberg: The hidden beauty of pollination

  1. Humans depend on pollinators for what proportion of the fruits and vegetables we eat?
  2. Identify three different kinds of animals that pollinate flowers.
  3. A large bumblebee was searching for nectar deep in a lavender flower blossom -- and kicking up a lot of tiny white particles. What were those particles?
  4. What animals were pollinating the large cactus plants?


There is something odd about the situations described below. See if you can identify the problem(s).

  1. A futurist proposes the building of a floating forest high in the atmosphere populated only by trees.
  2. A plant chemist is doing an experiment by growing green algae in a test tube filled with water. After a few hours, she notices tiny bubbles accumulating inside the test tube.
  3. Why does drowning kill people?
  4. A performance artist announces that he will perform a stunt in which he lives for a month on a diet made up entirely of paper, declaring “Termites can do it, why can’t humans?”
  5. Bernice dutifully cares for her new house plants by watering them regularly and making sure they get the necessary amount of sun. At first, they do very well, growing rapidly. But after a few months, they start to turn pale. Bernice tries more water, but that doesn’t seem to help.
  6. Photosynthesis captures sunlight and uses it to make fixed carbon, some of which is used to make sugar which stores the energy in its chemical structure. Seems inefficient. Why not just store the sunlight directly?
  7. In terms of cell energetics, what is drowning?
  8. A recent MBA graduate working for a landscape supplier has a brilliant scheme for saving money on shipping costs. He proposes cutting off the heavy plant roots and only shipping the above-ground part of the plant.
  9. All plants seem to need as much sunlight as they can get.
  10. How can honeybees know exactly what to do in order to fertilize flowers?
  11. Why would you not want to be invited to a rabbit’s house for dinner?
  12. While on a luxury rain forest safari to the Amazon, your guide suggests that your group turn back on your walking path. The reason: ants. “Oh pshaw,” you say. “What big, strong, tough red-blooded American is afraid of a few ants?”
  13. Why are cat faces so cute?
  14. Food chains aren’t.
  15. While exploring the tropical savanna of Africa, Manpreet observed so many gazelles, so few lions.
  16. On an infomercial, survivalist, Rex Quan do says, “The only way to survive is ATTACK ATTACK ATTACK!”

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