![Lt L6 L.J c
the birds don't like? The researcher had a hunch; she suspected that the striped butter-
flies tasted bad and that their bright colors acted as a sort of "warning" to predators to
stay away. This kind of tentative explanation is called a 8--.--.-.-.
The zoologist decided to test this in the laboratory, under conditions that she
could manipulate and monitor. Such a test is called a controlled 9
She captured insect-eating birds native to the area and put them in cages at a nearby re-
search station. Then she netted a number of brightly striped butterflies and their black
cousins. For her first experiment, she allor,r,ed the birds to choose between a black butter-
fly and a striped one. The birds invariably chose the black butterflies and avoided the
striped ones. This confirmed her field observations.
But did the striped butterflies taste bad? The researcher set up another controlled
experiment, designed to compare an 10 group-striped butterfl ies
rn'ith their wings painted black-with a i1 group of "normal" striped
butterflies. (Actually, the "normal" butterflies were also handled and painted with clear
paint, so that only one 12 wouid differ between the two groups.) Her
hypothesis led the zoologist to make a 13 about how she thought the
experiment would turn out: f the stripes really acted as a warning, then the birds would
be fooled and eat the butterflies when the stripes were corered-and that the striped
f
butterflies tasted bad, then the birds would spit them out. Such "if-then" thinking is
called la and is an important feature of hypothesis-driven science.
]ust as the researcher hypothesized, the birds chose the black-painted butterflies
in every trial. Also, most of the birds quickly spat out the black-painted butterflies, and
those that swallowed the butterflies became ill. Just to cover things, the zoologist per-
formed another experiment in which she painted the wings of the edible black-winged
butterflies. The birds ate them with gusto, demonstrating that the paint itself was not dis-
tasteful and produced no ill effects.
After repeating the experiments several times, the researcher wrote a paper de-
scribing her hypothesis, experiments, results, and conclusions. It was published in the
lournnl of Tropicnl Entotnology. There other scientists could read about the experiments,
repeat and expand upon them, even challenge the results-all part of the process of
science.
After reading these modules, and without referring back to the text, list six ways in which
you think the science of biology and its technological applications may affect society in
the next decade. Which of these are primarily scientific? Which are technological? Are any
of them related to evolution, the core theme of biology? A/hich do you think will have the
most effect on you personally in the coming years?](https://image.slidesharecdn.com/ch1homework-100829203312-phpapp01/85/Ch-1-homework-6-320.jpg)
Ch 1 homework
- 1. Clnpter 1 This module discusses the hierarchy of structural levels into which life is organized. Each of these levels has unique emergent properties, n'hich arise from the organization of its component parts. Review this structural hierarchy by completing the chart below. Leoel Desuiption 1. AII environments on Earth that support life Ecosystem J. AII the organisms in a particular ecosystem Population 5. An individual living thing 6. Organs that work together to perform particular functions Organ 8. A group of similar cells with a specific function 9. A living unit, separated from its environment by a membrane Organelle 10. 11. A cluster of atoms held together by bonds
- 2. Biology : Exploring Life s.3 This module describes how organisms interact with their environments. Review the web of interactions by completing this crossword puzzle. Across Down 2. Chemical cycle within the ecosystem's 1. such as bacteria and fungi convert dead web of species. matter to simpler nutrients. 4. -food that supports the ecosystem. 3. - dynamics of an The involve flow of en- 7, the main producers in a forest. ergy and recycling of nutrients. - -make 9. Rabbits function as in an ecosystem. 5. The exchange of matter and energy in an -are ecosystem involves a complex web of 10. comes into an ecosystem in the form of sunlight. - 6. In an ecosystem, there are many interactions - L1.. Decomposers chemical nutrients. -. among organisms, and between organisms and 13. Plants carry out . producing food for their _ environment. other organisms. - 8. Chemical is the fundamental level of 74. consumers: they eat plants and each order that underlies all the properties of life. other. - 12. Plants absorb mineral nutrients from the -are
- 3. 4 Chnpter 1 All living things are built from complex systems called cells. Cells are the smallest units that display the properties of life. AII cells are controlled by the genetic information in DNA molecules. These two modules briefly discuss the structure and function of cells and DNA and other features shared by all living things. Write a paragraph describing how an or- ganism familiar to you-a college student-displays these features of life. Rer.iew the three domains of life by matching each statement on the right with the correct domain. Write your answer in the first column. In addition, name the kingdom for each of the organisms in Domain Eukarya, and write your answer in the second column. Choose from: Domain Bacteria Domain Archaea Domain Eukarya protists (several kingdoms) Kingdom Plantae Kingdom Fungi Kingdom Animalia Donmin Kingdont 1. Tree and fern 2. Prokaryotes 3. Another domain of prokaryotes 4. Multicellular eukarvotes that ingest (eat) other organisms 5. Molds, yeasts, and mushrooms 6. Algae and protozoa 7. Organisms whose cells lack a nucleus 8. Brown pelican, sloth, and spider 9. Multicellular photosynthetic organisms with rigid cellulose cell walls 10. Singie-celled eukaryotes such as an amoeba
- 4. DtuLUXV. L-tytvt ttL6 LLJc Eyolution is biology's core theme. It explains the diversity of life, the relatedness of all liv- ing tirings, and the aclaptation of living things to their environments. Fill in the blanks in the following story to revier.t' the concepts of errolution. While investigating the insect life of the rainforest canoPy, a zoologist captured serreral specimens of a previously unknorvn species of butterfly. The butterfly r'r'as mostly black but had conspicuous red and yellow stripes on its rt'ings. It rested on bare tree limbs in plain vier.t'; the zoologist was surprised she had not seen it before. The butterfly was very similar in structure to that of a much less conspicuous all-black species found in the same general area, so the zoologist figured that thc tn'o species lvere closely members of the sarne family. Biologists have long marveled at the diversity of insect life in the tropics. Ias sur- , the English biologist tt'iro r,r'rote Tlrc Origirt of Species, prised by the large nurnber of insect species he encountered in the rain forests of South America. In fact, biologists estimate that most species of living things are rain forest insects. Like Darwin, tl-re zooiogist concluded that the black butterfly aud the new species looked alike because they rvere botir descendecl from a commoll species. But n'hy the differer-rce in color pattern? When she first en- countered the striped butterflies, shc speculated that the red and yellon' stripes '/ere an evolutionary adaptation, a beneficial feature that evoir.ed by means of natural selection. But horv could a bright color pattern be of any possible benefit? Wouldn't brightly col- ored butterflies be attacked by predators? Her suspicions intensified rt4ren the zoologist sarv the red and yellorv r,r'inged butterflyrestilrgorratLeelimb.Apredatorybirdlarrdedrrearbl,alrdpeeredatt}rebtrtter- fly. The butierfly responded by rapidly tlapping its r,r'iugs, displaf ing their striped pat- tern, and the bird flew off. This is r.r'hat first caused the zoologist to suspect that the bright wing pattern /as an example of "tt,arning coloration," oftetr seen in harmful or bad-tasting animals-for example, the conspicuor-rs yel1on and black stripes of bees aird rn'asPs. How could such a color pattern finyg g1zsl1'gd in this species of butterfly? The zooiogist speculated that at one time a 4 of black butterflies existed in this area, breeding among themselves but not tt'ith other mernbers of their species. These butterflies exhibited traits-siightly different wing shapes, sizes, behaviors, and so on' They also may have tasted different. Perhaps sol11e ,vere able to rnake a bad-tasting sub- stance or store a bad-tasting substance obtained from food plants. just as Darwin rea- soned, the zoologist realized that 6 variation mttst be present in tire population for natural selection to operate. Also like Darn'in, she realized that there is great overproduction of offspring-many more btttterflies are produced each year than can possibly surrrive. In this population, it appeared that among this abundance of but- terfly prey, the good-tasting buttelflies r.t'ere more likely to be eaten by thtrn bad-tasting oues. The surviving bad-tasting butterflies r.vere more likely to surr,il'e to 8 , and they passed their ability to make the bad-tasiing chemical on io their 9 . Ovel timc, this
- 5. 6 Chopter 1 10 trait accumulated in the population-the bad-tasting butterflies became more numeroLrs. What about the difference in color pattern? The zoologist speculated that among the bad-tasting butterflies, there may have been variation in wing coloration. Butterflies n'ith bright colors on their r.r'ings were easier for predators to remember and avoid. The colorful butterflies had more offspring than less-conspicuous individuals-they had i1 reproductive success, Eventually bright-colored, bad-tasting but- terflies became the norm in the population. In this situation, as in others expiained by Charles Darn'in, 12 occurs as heritable 13 are ex- 14 15 posed to factors that far.or the success of some individuals over others. The zoologist speculated that, over a long period, the changes in palatability, wing pattern, and other characteristics must have combined, and a whole new 16 of butterfly came into existence. According to Danvin, the 17 of new species results from the accumulation of minute changes resulting from natural selection over 18 . This short story is just one 19 Evolution is an important illustration of evolution, biology's core 20 of life (descent from a common idea, because it explains both the ancestor) and 2i of life (modification as species diverged from their ancestors). Review the scientific method by filling in the blanks in the following story. Choose from factor, hypothesis, question, inductive reasoning, control, prediction, deductive reasoning, discovery, observation, experiment, experimental, and scientific method. Answers may be used more than once. In Exercise 5, you read how a zoologist identified a previously unknown species of butterfly. This species was mostly black, but had conspicuous red and yellow stripes on its wings. It was very similar in appearance and structure to an all-black species found in the same area. Carefully comparing the trvo species, the zoologist concluded that they were closely related-members of the same family. Looking at many examples (of butter- flies) and deriving a general principle (the characteristics of the butterfly family) employs a kind of logic called r . This kind of thinking is often involved when a scientist does 2 science, which is mostly concerned with describing nature. A different process is followed when a scientist seeks to develop an explanation for natural events. This second method of inquiry is called 3 -based 4 science. It employs a process of inquiry sometimes called the Although it is not a single method, its key element is the kind of logic called 5 In our example, like many examples of hypothesis-based science, the process started rvith a simple 6 : The zoologist noticed that predatory birds avoided the brightly colored butterflies even though they rested in tree branches in plain sight. This evoked a 7 : Is there something about the butterflies that
- 6. Lt L6 L.J c the birds don't like? The researcher had a hunch; she suspected that the striped butter- flies tasted bad and that their bright colors acted as a sort of "warning" to predators to stay away. This kind of tentative explanation is called a 8--.--.-.-. The zoologist decided to test this in the laboratory, under conditions that she could manipulate and monitor. Such a test is called a controlled 9 She captured insect-eating birds native to the area and put them in cages at a nearby re- search station. Then she netted a number of brightly striped butterflies and their black cousins. For her first experiment, she allor,r,ed the birds to choose between a black butter- fly and a striped one. The birds invariably chose the black butterflies and avoided the striped ones. This confirmed her field observations. But did the striped butterflies taste bad? The researcher set up another controlled experiment, designed to compare an 10 group-striped butterfl ies rn'ith their wings painted black-with a i1 group of "normal" striped butterflies. (Actually, the "normal" butterflies were also handled and painted with clear paint, so that only one 12 wouid differ between the two groups.) Her hypothesis led the zoologist to make a 13 about how she thought the experiment would turn out: f the stripes really acted as a warning, then the birds would be fooled and eat the butterflies when the stripes were corered-and that the striped f butterflies tasted bad, then the birds would spit them out. Such "if-then" thinking is called la and is an important feature of hypothesis-driven science. ]ust as the researcher hypothesized, the birds chose the black-painted butterflies in every trial. Also, most of the birds quickly spat out the black-painted butterflies, and those that swallowed the butterflies became ill. Just to cover things, the zoologist per- formed another experiment in which she painted the wings of the edible black-winged butterflies. The birds ate them with gusto, demonstrating that the paint itself was not dis- tasteful and produced no ill effects. After repeating the experiments several times, the researcher wrote a paper de- scribing her hypothesis, experiments, results, and conclusions. It was published in the lournnl of Tropicnl Entotnology. There other scientists could read about the experiments, repeat and expand upon them, even challenge the results-all part of the process of science. After reading these modules, and without referring back to the text, list six ways in which you think the science of biology and its technological applications may affect society in the next decade. Which of these are primarily scientific? Which are technological? Are any of them related to evolution, the core theme of biology? A/hich do you think will have the most effect on you personally in the coming years?