ux1.eiu/~gabulla

1. www.ux1.eiu.edu/~gabulla

2. www.ux1.eiu.edu/~cfgab Lectures saved as Html files.. …and powerpoint files Click on “Chapter 1“

3. If you have Microsoft Powerpoint: -You can print out the lectures 6 slides /page To print- 1. Select File- Print 2. In the pop-up window, select… Slides “6” slides per page Handouts OK Pure black and white

4. Dishonesty

5. Life resists a simple, one-sentence definition, yet we can recognize life by what living things do. Fig. 1.2

6. CHAPTER 1 Exploring Life 1. Hierarchy of life • Life’s basic characteristic is a high degree of order. Atoms Biological molecules Organelles • Basic unit of life Cells Multicellular Tissues Unicellular Organs Organ system

7. Organisms belong to populations, localized group of organisms belonging to the same species. Populations of several species in the same area comprise a biological community. These populations interact with their physical environment to form an ecosystem. Fig. 1.2(6) The biosphere refers to all life on earth

8. Energy flow proceeds from sunlight to photosynthetic organisms (producers) to organisms that feed on plants (consumers). Fig. 1.4

9. All organisms must accomplish the same functions: • uptake and processing of nutrients • excretion of wastes • response to environmental stimuli • reproduction

10. The cell = lowest level of structure that is capable of performing all the activities of life.. 1b. Cells are an organism’s basic unit In 1839, Matthais Schleiden and Theodor Schwann • The cell theory- all living things consist of cells. • A cell theory extension - all cells come from other cells.

11. Novel properties emerge at each step upward in the biological hierarchy. • Result from interactions between components. • A cell is not just a bag of molecules.

12. encodes life. is the substance of ________ 1c. DNA is the cell’s heritable information DNA (deoxyribonucleic acid) genes • is composed of two long chains arranged into a_________________. • Contains only four molecules called______________ . double helix nucleotides genetic code • All forms of life employ the same __________________. • Cells ____________chromosomes and provide an exact copy to two “daughter” cells Fig. 1.7 replicate

13. All cells: Are enclosed by a _______________ regulates the passage of materials Contain ________ Two major kinds of cells – _______________– (yeast to mammals) ___________- contains chromosomes (DNA + protein) ______________ - contains membrane- bound organelles Sometimes a cell wall (plants) _____________–includes bacteria and archaea no nucleus, no organelles, DNA in cytoplasm membrane DNA eukaryotic Nucleus Cytoplasm prokaryotic

14. The complex organization of life is a dilemma We cannot fully explain a higher level of organization by breaking down to its parts. At the same time, it is futile to try to analyze something a complex as an organism or cell without taking it apart. Reductionism, reducing complex systems to simpler components, is a powerful strategy in biology. Reductionism is balanced by the longer-range objective of understanding emergent properties. 2a. Emergent properties- more than the sum of the parts

15. Where can I look to find answers?? Fig. 1.10- A map of protein interactions in a cell Bioinformatics- extracting biological information from huge databases Computer-based mathematical modeling is a must Requires engineers, chemists, physicists, mathematicitians, biologists

16. Organisms obtain useful energy by breaking down molecules in regulatedchemical reactions. Special protein molecules, called enzymes, catalyze these chemical reactions. Enzymes speed up these reactions enzymes catalyze the rapid breakdown of sugar molecules when need energy At rest, other enzymes store energy in complex sugars. 2b. Feedback regulation is important

17. Many biological processes are self-regulating Negative feedback or feedback inhibition slows or stops processes. Positive feedbackspeeds a process up. Fig. 1.11 Fig. 1.12

18. 3. Diversity of Species • Diversityis a hallmark of life. • 1.8 million species identified. • Includes over 290,000 plants, 52,000 vertebrates, and over 1,000,000 insects. • Thousands of newly identified species are added each year. • Estimates of the total diversity of life range from about 5 million to over 30 million species. Fig. 1.13

19. Pre 1990- five kingdoms. • Today- Various classification schemes now include six, eight, or more kingdoms. • Debate that there are three even higher levels of classifications, the domains. • The three domains are the Bacteria, Archaea, and Eukarya. • Taxonomyis the branch of biology that names and classifies species into a hierarchical order. Fig. 1.14

20. Both Bacteria and Archaea are prokaryotes. • Archaea may be more closely related to eukaryotes than they are to bacteria. • The Eukaryaincludes at least four kingdoms: . Protista, Plantae, Fungi, and Animalia Bacteria Protists Plantae Fig. 1.15 Archaea Fungi Animalia

21. Charles Darwin (1859) presented two main concepts in The Origin of Species. Fig. 1.17 Fig. not in text 4. Evolution accounts for diversity and unity • Life evolves and this process is called evolution. • Evolution is a theory that has become dogma • It is based on extrapolation from data from many sources. 1. Contemporary species arose from a succession of ancestors through “descent with modification” (evolution). 2. The mechanismof evolution is natural selection.

22. Darwin inferred that those individuals with traits best suited to the local environment will generally leave more surviving, fertile offspring. Differential reproductive success is natural selection. Fig. 1.21 8. Evolution is the core theme of biology

23. Natural selection, over vast spans of time, may produce new species from ancestral species. Fig. 1.23 8. Evolution is the core theme of biology • EXAMPLE: The finches of the Galapagos Islands diversified after an initial colonization from the mainland to exploit different food sources on different islands.

24. The word science is derived from a Latin verb meaning “to know”. 5. Science is a process of inquiry that includes repeatable observations and testable hypotheses • Science seeks natural causes for natural phenomena. • The scope of science is limited to processes that we can observe and measure, either directly or indirectly. • Verifiable observations and measurements are the data of discovery science.

25. The scientific method consists of a series of steps. • Few scientists adhere rigidly to this prescription, but at its heart the scientific method employs hypothetico-deductivereasoning. Fig. 1.25

26. Case of Scientific inquiry- Snake mimicry harmless Question- Do harmless king snakes benefit from looking like a deadly coral snake? Prediction- King snakes will be not be attacked as often where the coral snake lives. Experiment-place plastic snakes out in both areas, examine for attack marks venomous Control? - plastic brown snakes to control for number of predators harmless Fig. 1.28 Fig. 1.27

27. Results: Conclusion- It’s good to look like a deadly snake

28. Scientific theories are not the only way of “knowing nature”. Various religions present diverse legends that tell of a supernatural creation of Earth and its life. Science and religion are two very different ways of trying to make sense of nature. Art is another way.

29. Science can be distinguished from other styles of ____________by (1) a dependence on _________________________ that others can verify, and (2) the requirement that ideas (hypotheses and theories) are ______________by observations and experiments that others can repeat. inquiry observations and measurements testable

30. Science and technology are associated. Technology results from scientific discoveries applied to the development of goods and services. The discovery of the structure of DNA by Watson and Crick sparked an explosion of scientific activity. These discoveries made it possible to manipulate DNA, enabling genetic technologists to transplant foreign genes into microorganisms and mass-produce valuable products. 5b. Science and technology are functions of society

31. DNA technology and biotechnology has revolutionized the pharmaceutical industry. • It has also had an important impact on agriculture and the legal profession. Fig. 1.32

32. Not all of technology is applied science. The direction that technology takes depends less on science than it does on the needs of humans and the values of society. Technology has improved our standard of living, but also introduced some new problems.