1.1 Introduction to Biology

1. 1.1 Introduction to Biology p. 4-10

2. Main Idea • All living things share the characteristics of life.

3. What is Biology? • Biology….. • is the science of life • examines how living things interact, how systems function, and how they function at a molecular level. • Biology studies….. • the origins and history of life and once-living things, • the structures of living things, • how living things interact with one another, • and how living things function.

4. What do Biologists do? • 1. Study the diversity of life • Ex. Jane Goodall studying chimpanzees. • 2. Research disease • Ex. Developing vaccines for small pox, chicken pox, AIDS, and other viral infections. • 3. Develop technologies • Ex. Bionic hand, artificial heart • 4. Improve agriculture • Ex. Develop drought resistant/insect resistant plants • 5. Preserve the environment • Ex. Save endangered species and habitats

5. What are the 8 Characteristics of Living Organisms? • 1. Made of one or more cells • 2. Displays organization • 3. Grows and develops • 4. Reproduces • 5. Responds to stimuli • 6. Requires energy • 7. Maintains homeostasis • 8. Adaptations evolve over time

6. What is an Organism? • An organism is anything that has or once had all of these 8 characteristics.

7. Made of One or More Cells • All organisms are made of one or more cells. • Unicellular … bacteria • Multicellular… animals

8. Displays OrganizationWhat is organization? • Organization means that living things are arranged in an orderly way. • Example: • Animals are made up of cells. • Those cells different types of cells are organized into tissues. • Different types of tissues work together to form organs. • Different organs work together to make up organ systems. • Organ systems work together to make up the entire organism.

9. Grows and DevelopsWhat is growth and development? • Growth results in the addition of mass to an organism, and in many organisms, the formation of new cells and new structures. • An oak tree will grow – get larger - throughout its lifetime. • Development is the process of natural changes that take place during the life of an organism. • An acorn develops into an oak tree.

10. ReproducesWhat is reproduction? • Reproduction is the production of offspring. • Organisms reproduce and pass along traits from one generation to the next. • For a species to continue to exist, reproduction must occur.

11. What is a species? • A species is a group of organisms that can breed with one another and produce fertile offspring.

12. Responds to StimuliWhat is a stimulus? • A stimulus is any change in an organism’s internal or external environment that causes the organism to react. • Internal environment- anything inside the organism • External environment- all things that surround the organism [air, temperature, soil, light, other organisms]

13. What is a response? • A response is the reaction to a stimulus. • Stimulus happens….. Then the response. • The light shines through a window on a plant. The plant grows toward the light. • A wolf chases a deer. The deer runs away. • Being able to respond to the environment is critical for an organism’s safety and survival.

14. Quick Check: • What is the stimulus and what is the response? • When a toxin is poured in a certain part of a lake, the fish in that area move away. • When a plant is plant doesn’t receive enough water, its leaves begin to wilt.

15. Requires Energy • Living things need sources of energy to fuel their life functions. • Plants make their own food. • Most organisms get their energy by consuming other organisms.

16. Maintains HomeostasisWhat is homeostasis? • Homeostasis is the regulation of an organism’s internal conditions • Example: When you get hot, you begin to sweat. That sweat helps to cool down your body, maintaining homeostasis of body temperature.

17. Adaptations Evolve Over TimeWhat is an adaptation? • An adaptation is any inherited characteristic that results from changes to a species over time. • The venus fly trap have adapted to nutrient/nitrogen poor soil by trapping insects and absorbing dissolved nitrogen and nutrients.

18. End of 1.1

19. 1.2 The Nature of Science p. 11 - 15

20. Main Idea • Science is a process based on inquiry that seeks to develop explanations.

21. What is science? • Science is a body of knowledge based on the study of nature.

22. What are characteristics of “good science”? • 1. It relies on evidence. • 2. It expands scientific knowledge. • 3. It challenges accepted theories. • 4. It questions results. • 5. It tests claims. • 6. It undergoes peer review. • 7. It uses the metric system.

23. 1. Relies on Evidence • Scientific explanations combine what is already known with consistent evidence gathered from many observations and experiments. • When enough evidence from many related investigations supports an idea, scientists consider that idea a theory.

24. What is a Theory? • A theory is an explanation of a natural phenomenon supported by many observations and experiments. • Cell theory • Theory of heredity

25. What is Pseudoscience? • Pseudosciences are those areas of study that try to imitate science, often driven by cultural or commercial goals. • physiognomy- judging someone’s character or personality based on physical features • Phrenology: reading the bumps on someone’s head • astrology and horoscopes • reading palms

26. 2. Expands Scientific Knowledge • The search for new knowledge is the driving force that moves science forward. • Nearly every new find causes scientists to ask more questions that require additional research.

27. 3. Challenges Accepted Theories • Scientists welcome debate about one another’s ideas. Often disagreements occur. Then additional investigations and/or experiments are done to find what works. • For example, many ideas about how HIV is transmitted and treated have changed due to new information.

28. 4. Questions Results • Observations and data different from current understanding are of interest to scientists. • For example, early biologists grouped bats and birds together because both have wings. Further study showed that bat wings were more like mammalian forelimbs.

29. 5. Tests Claims • Whenever biologists do research, they use standard experimental procedures called controlled experiments.

30. 6. Undergoes Peer Review • Peer review is a process by which the procedures used for an experiment and the results are tested by other scientists in that area of study.

31. 7. Uses Metric System • The metric system uses units with divisions that are powers of 10.

32. What is SI? • The International System of Units • Examples: • meter – used to measure length • Gram – used to measure mass • Liter – used to measure volume • Second – used to measure time

33. Science in Everyday Life • In order to understand the huge amount of information about science available in print, on line, and on TV, and to participate in the fast-paced world, each of us must be scientifically literate. • Many issues faced every day relate to the world of biology. • Drugs, alcohol, tobacco, AIDS, mental illness, cancer, heart disease

34. Science in Everyday Life • There are many issues you and future generations will face. Many involve ethics, which is a set of moral principles or values. • Euthanasia- permitting death for reasons of mercy • Cloning- producing genetically identical individuals • Cryonics- freezing a dead person or animal with the hope of reviving it in the future

35. 1.3 Methods of Science p. 16 - 21

36. Main Idea • Biologists use specific methods when conducting research.

37. What are the Methods of Science? • 1. Ask a question • 2. Form a hypothesis • 3. Collect Data • 4. Analyze the Data • 5. Report Conclusions

38. Ask a Question • Scientific inquiry (scientific asking questions) begins with observation. • Observation is a direct method of gathering information in an orderly way. • Observation is combined with • collecting information, • prior knowledge, and • related research. • Make inferences.

39. What is an inference? • An inference is combining what you have observed with what you already know and making logical conclusions. • Example: • I have seen it rain when the sky becomes very dark and cloudy. I know that rain comes from clouds. I can infer that when the sky becomes dark and cloudy, it will rain.

40. What is the scientific method? • The scientific method is attempting to answer a question by: • 1. making observations • 2. ask a question • 3. forming a hypothesis • 4. experimenting • 5. collecting and analyzing data • 6. and drawing conclusions

41. Form a Hypothesis • A hypothesis is a testable explanation of a situation.

42. What is an experiment? • An experiment is an investigation done in a controlled setting to test a hypothesis.

43. Controlled Experiment • A controlled experiment has two groups– a control group and an experimental group. • Control group: the group in an experiment used for comparison • Experimental group: the group in an experiment exposed to the factor being tested

44. Quick Check: • In my experiment, I am testing the effects of plant food on plant growth. I have 3 plants. Plant A will receive the recommended amount of plant food. Plant B will receive twice the amount of plant food. Plant C will not receive any plant food. • What is the control group and what is the experimental group?

45. Experimental Design • When scientists design a controlled experiment, only one factor can change at a time—the independent variable. • Independent variable: the tested factor • Scientists measure a second factor—the dependent variable. • Dependent variable: results from or depends on changes to the independent variable

46. Quick Check: • In our plant experiment….. • What is the independent variable? • What is the dependent variable? What do we want to see?

47. Experimental Design • A constant is a factor that remains fixed during an experiment while the independent and dependent variables change. • In our plant experiment, some constants may be amount of sunlight, type of soil, type of plants

48. Data Gathering • As scientists test their hypotheses, they gather data– information gained from observations. • Quantitative: numbers – measurements of time, distance, mass, volume • Qualitative: descriptions of what our senses detect

49. Analyze the Data • As biologists look for explanations, patterns are usually found to help explain the data. • The data is organized in tables and graphs. • The graphs make patterns easier to see and understand.

50. Analyze the Data • Analysis of the data might lead to….. • a conclusion the the hypothesis has been supported. • additional hypotheses. • further experimentation. • Even when a hypothesis has not been supported, it is valuable.