Introduction to Biology

1. Introduction to Biology Chapter 1

2. Cytoskeleton-cell skeleton • Arthropod-jointed-footed • Herbivore-plant eater • Hypothermia-below body temperature • Chemosynthesis-chemicals making something • Photosynthesis-light making something • Cardiology-study of the heart • Heterotroph-different feeding • Autotroph-self-feeding • Biotic-Living • Abiotic-Living • Monosaccharide-1 sugar • Disaccharide-2 sugars • Polysaccharide-many sugars Using prefixes and suffixes to define unfamiliar words

3. Cytoplasm-cell substance • Epidermis-outer skin • osteocyte-bone cell • Glycolysis-break down sugar • Herbology-study of plants medicinally • Exoskeleton-outer skeleton • Antibiotic-against life • Trophic level-feeding level • Hemophilia-blood disease • Hyperthermia-above body temperature • Dermatitis-skin inflammation

4. Biology-the study of living things • The Goal of Science: • Deals with the natural world • To collect and organize data • Propose explanations that can be tested What is Science?

5. Science-the process of investigating and trying to understand the natural world, by finding explanations and using explanations to make predictions. • Science begins with “observations” Data-information gathered from observations. • Quantitative-numerical data (graphs, tables, mathematical equations) • Qualitative-non-numerical data (Pictures, the color, texture, or appearance of something) What is Science?

6. Scientists may use data to make an inference. • Inference-a logical interpretation based on prior knowledge or experience. • Ex: Researchers testing water for pollution cannot test every drop. If all drops come back clean, they may infer that all water is safe to drink. • If it is snowing outside, you may infer that it is cold. Hypothesis vs. Inference

7. Steps to the Scientific Method: • Ask a question, make observations • Gather information • Form a hypothesis • Set up a controlled experiment • Record and analyze data-(inference possibly made) • Draw conclusions • Repeat to try and achieve the same result What is Science?

8. Ask initial question • After initial observations, researchers propose one or more hypotheses • Hypothesis-a well-researched, proposed scientific explanation for your question. • Design experiment which tests your hypothesis(es) Experimental Design

9. Experimental Variables: • Independent (manipulated)-manipulated by researcher • Dependent (responding)-responds to changes in independent • Constants-variables that are kept unchanged between test groups. • Control variable-a variable that is not manipulated in one group to act as a standard for comparison Experimental Design

10. Scenario 1 Peat Moss and Sand • Norm wanted to know if adding peat moss to sand would affect its ability to hold water. He put 200mL of pure sand into container A. He put a mixture of 80% sand and 20% peat moss into container B. He put a mixture of 60% sand and 40% peat moss into container C. He put a mixture or 40% sand and 60% peat moss into container D. He added water to each container and measured the amount of water the contents would absorb. He dried the sand and peat moss and repeated the experiment 5 times. • Question? Quantitative Data? • Hypothesis? Qualitative Data? • Variables? • Conclusion? Experimental Design

11. Theory-a well-supported explanation based on many repeated experiments, and supported by many facts. • Theories explain scientific facts and are not observable • Withstands attempts to disprove • Help guide further research and have shaped science as we know it today. • Facts are what we observe and theories confirm facts Theory vs Law

12. Law-identifies and describes patterns of behavior found in nature. • Not a mature theory (Theories do NOT become laws) • Many times describe through mathematical terms • Ex: Einstein’s Theory of Relativity helped to further explain Newton’s Laws. Newton only described gravity’s behavior in precise mathematical terms, but did not explain gravity’s behavior. Theory vs Law

13. Biology-the science of studying living things. Is a flame alive? How do you know 100%? • Living things share the following characteristics: • Made up of cells • Reproduce • Have DNA (genetic code) • Grow and develop • Obtain and use materials and energy • Respond to their environment • Maintain stable, internal environment by homeostasis • As a group, change over time Characteristics of Living Things

14. Organism-a living thing made up of one or many cells • Unicellular- composed of only one cell • Ex: Bacteria, amoeba Living Things are Made up of Cells

15. Multicellular-composed of more than one cell. • Ex: Humans (100,000,000,000,0000 cells) • 100 trillion Characteristics of Living Things

16. Reproduction-process by which organisms produce offspring. • Sexual-involves two parents; sperm and egg ( two gametes)-more complex • Ex: Humans to create offspring • Advantageous for genetic variation • Asexual-Type of reproduction involving only one parent (offspring are genetically identical to parent) • Ex: Bacteria, starfish • Can be advantageous if organisms is not mobile and does not expend too much energy Living Things Reproduce

17. DNA-(deoxyribonucleic acid)-a molecule that encodes the genetic instructions used in by all living organisms for development and functioning. Living Things Contain DNA

18. Development-Series of orderly changes that occur in an organism’s life. • 5 Stages of Development: • Beginning-fertilization of egg • Growth-the number of cells increases • Maturity-the number of cells is not increasing. Cells are being replaced and repaired. • Decline-Cells are no longer being repaired or replaced. • Death-All cell activity ceases. Growth and Development

19. Energy-the ability to cause a change or do work. • Metabolism- combination of all of the chemical reactions involved in maintaining the living state of the organism and it’s cells. • Since living things are in a constant state of chemical activity, they require energy. • Humans must eat food to get energy, while plants use the sun to make food. BOTH must break down food to release energy. • Life continues only as long as an organism can obtain and use energy. • All energy comes originally from the SUN!! Living Things Need Materials and Energy

20. Environment-all living and nonliving things around an organism • Stimulus-Anything that causes a reaction • Ex: light, sound, pressure, and temperature • Response: An organism’s reaction to a stimulus • Ex: the human eye’s response to light Living Things Respond to Their Environment

21. Homeostasis-an organism’s ability to maintain a constant or stable internal condition necessary for life. • Ex: blood pressure, heartbeat, breathing rate, etc. Living Things Maintain a Stable Internal Environment

22. Adaptation-inherited characteristics that increase an organism’s chance for survival. • Individual organisms respond. • Living things do not change to survive; the survive because a change has taken place. • Variation allows for adaptation. As a Group, Living Things Change Over Time

23. Biosphere-all ecosystems on Earth • Ecosystem-a community and its nonliving surroundings • Community-Populations that live together in a defined area. • Population-a group of organisms of one type that live in the same area. • Organism-an individual living thing. • Groups of Cells-Tissues, organs, and organ systems. • Cells-the smallest functional unit of life. • Molecules-groups of atoms; smallest unit of most chemical compounds. Levels of Organization

24. Data can be expressed in graphs and data tables: Line graphs-used for data that fluctuates constantly Ex: temperature over time Bar graphs-used for counted data Ex: number of students in each classroom Graphing

25. Independent variable gets plotted on the x-axis. • Dependent variable gets plotted on the y-axis. Graphing

26. Graphing

27. Types of Microscopes Microscopes-devices that produce magnified images of structures that are to small to see with the unaided eye. Compound Light Microscopes-allow light to pass through a thin specimen of an image to produce an images. • Most common • Magnification=4-1000x • Resolution=good • Advantages-Can view live organisms, cheaper • Disadvantages=Can’t see 3-D, magnification not as good Using the Microscope

28. Light Microscope

29. Transmission Electron-shine a beam of electrons through a thin specimen. • Magnification=200,000 x (internal) • Resolution= very good • Magnifies by beams of electrons • Advantages=extreme resolution inside of organisms • Disadvantages=can’t see 3-D, can’t view live organisms because requires a vacuum. Electron Microscopes

30. Transmission Electron Microscope

31. Scanning Electron Microscope-scan a narrow beam of electrons back and forth over the surface of a specimen. • Magnification=500,000 x surface • Resolution=very good • Magnifies by electrons • Advantages=can view whole organisms • Disadvantages=can only view surface of dead organisms. Electron Microscopes

32. Electron Microscopes

33. Scanning Probe Microscope-forms images of surfaces by scanning a probe over the surface of the specimen. • Magnification= 10,000,000x • Resolution=extremely good • Uses a scanning probe to magnify image • Advantages=can see details of very small images (not constrained to the wavelength of light or electrons.)-still being developed with “Nanoscience” • Disadvantages=smaller pictures, possibly longer wait time for image, some probes better than others Electron Microscopes

34. Electron Microscopes