Chapter 1: Exploring Life

1. Chapter 1: Exploring Life

2. History is a vital tool in learning about science. Charles Darwin Louis Pastuer

3. Figure 1.1

4. Biology is the science that focuses on life

5. Order Response to the environment Figure 1.3 Evolutionary adaptation Reproduction Regulation Energy processing Growth and development

6. 2 Ecosystems 3 Communities 4 Populations 5 Organisms Exploring Levels of Biological Organization 1 The biosphere

7. 1 µm 8Cells Cell 9Organelles Atoms 10Molecules 7Tissues 10 µm 50 µm 6Organs and organ systems

8. Basic scheme for energy flow through an ecosystem Sunlight Figure 1.5 Leaves absorblight energy fromthe sun. Leaves take incarbon dioxidefrom the airand releaseoxygen. CO2 O2 Cyclingofchemicalnutrients Animals eat leaves and fruit from the tree. Leaves fall tothe ground andare decomposedby organismsthat returnminerals to thesoil. Water andminerals inthe soil aretaken up bythe treethroughits roots.

9. Inherited DNA directs development of an organism Figure 1.10 Sperm cell Nuclei containing DNA Fertilized egg with DNA from both parents Embyro’s cells with copies of inherited DNA Egg cell Offspring with traits inherited from both parents

10. Nucleus DNA Cell A C Nucleotide T A T A C C G T A G T A (a) DNA double helix. This model shows each atom in a segment of DNA. Made up of two long chains of building blocks called nucleotides, a DNA molecule takes the three-dimensional form of a double helix. (b) Single strand of DNA. These geometric shapes and letters are simple symbols for the nucleotides in a small section of one chain of a DNA molecule. Genetic information is encoded in specific sequences of the four types of nucleotides (their names are abbreviated here as A, T, C, and G). DNA: The genetic material

11. Contrasting eukaryotic and prokaryotic cells in size and complexity Prokaryotic cell Eukaryotic cell DNA (no nucleus) Membrane Membrane Figure 1.8 Cytoplasm Nucleus(membrane-enclosed) DNA (throughoutnucleus) Membrane-enclosed organelles 1 m

12. Modern biology as an information science

13. A Negativefeedback Enzyme 1 B D Enzyme 2 Excess Dblocks a step. D D C C Figure 1.13 Enzyme 3 D (a) Negative feedback W Enzyme 4 X Positive feedback  Enzyme 5 Excess Zstimulates a step. Z Y Z Z Enzyme 6 Z (b) Positive feedback

14. Drawers of diversity

15. Species Genus Family Order Class Phylum Kingdom Domain Ursusameri- canus (American black bear) Ursus Ursidae Carnivora Mammalia Chordata Animalia Eukarya Classifying life

16. Exploring Life’s Three Domains (a) Domain Bacteria (b) Domain Archaea 2 m 2 m (c) Domain Eukarya Kingdom Animalia 100 m Kingdom Plantae Protists Kingdom Fungi

17. 15 µm 1.0 µm Cilia of Paramecium.The cilia of Parameciumpropel the cell throughpond water. 5 µm Cross section of cilium, as viewed with an electron microscope Cilia of windpipe cells. The cells that line the human windpipe are equipped with cilia that help keep the lungs clean by moving a film of debris-trapping mucus upward. An example of unity underlying the diversity of life: the architecture of cilia in eukaryotes

18. Digging into the past

19. Charles Darwin in 1859, the year he published The Origin of Species

20. Unity and diversity in the orchid family

21. Summary of natural selection Population of organisms Overproduction and struggle for existence Hereditary variations Differences in reproductive success Evolution of adaptations in the population

22. Natural selection 1 Populations with varied inherited traits 2 Elimination of individuals with certain traits. 3 Reproduction of survivors. 4 Increasing frequency of traits that enhance survival and reproductive success.

23. Form fits function

24. Descent with modification: adaptive radiation of finches on the Galápagos Islands Green warbler finchCerthidea olivacea Warbler finches Insect-eaters Gray warbler finchCerthidea fusca COMMONANCESTOR Sharp-beakedground finchGeospiza difficilis Seed-eater Vegetarian finchPlatyspiza crassirostris Bud-eater Mangrove finchCactospiza heliobates Woodpecker finchCactospiza pallida Insect-eaters Tree finches Medium tree finchCamarhynchus pauper Large tree finchCamarhynchus psittacula Figure 1.22 Small tree finchCamarhynchus parvulus Large cactusground finchGeospiza conirostris Cactus-flower-eaters Cactus ground finchGeospiza scandens Ground finches Small ground finchGeospiza fuliginosa Seed-eaters Medium ground finchGeospiza fortis Large ground finchGeospiza magnirostris

25. Observations Questions Hypothesis # 1:Dead batteries Hypothesis # 2:Burnt-out bulb Prediction: Replacing bulb will fix problem Prediction: Replacing batteries will fix problem Test prediction Test prediction Test falsifies hypothesis Test does not falsify hypothesis A campground example of hypothesis-based inquiry

26. Figure 1.23

27. Flower fly(non-stinging) Honeybee (stinging) A stinging honeybee and its nonstinging mimic, a flower fly

28. Science as a social process

29. Eleven Themes that Unify Biology