1. Biology in the 21 st Century Biology I(1) Mr. Scott

2. 1-1 The Study of Life Earth is home to an incredible diversity of life. Earth is home to an incredible diversity of life. The biosphere includes all living things and all the places they are found. The biosphere includes all living things and all the places they are found.

3. 1-1 The Study of Life Earth is home to an incredible diversity of life. Earth is home to an incredible diversity of life. Every part of the biosphere is connected with every other part. Every part of the biosphere is connected with every other part. The biosphere includes many environments. The biosphere includes many environments. Land environments Land environments Water environments Water environments Your body? Your body?

4. 1-1 The Study of Life The biosphere includes many environments. The biosphere includes many environments. n Saltwater and freshwater environments n Portions of the atmosphere Tidepool Estuary

5. 1-1 The Study of Life Biodiversity is the variety of life. Generally increases from the poles to the equator. Greater in areas with consistently warm temperatures.

6. 1-1 The Study of Life A species is one particular type of living thing. A species is one particular type of living thing. Members of a species can interbreed to reproduce. Members of a species can interbreed to reproduce. There are about 2 million different living species have been identified. There are about 2 million different living species have been identified.

7. 1-1 The Study of Life Biology is the scientific study of all forms of life. Biology is the scientific study of all forms of life. All organisms share certain characteristics. All organisms share certain characteristics. Organisms can be single celled or multicellular Organisms can be single celled or multicellular

8. 1-1 The Study of Life An organism is any individual living thing. An organism is any individual living thing. All are made of one or more cells. All are made of one or more cells. All need energy for metabolism. All need energy for metabolism. All respond to their environment. All respond to their environment. All have DNA that they pass on to offspring. All have DNA that they pass on to offspring.

9. 1-2 Unifying Themes of Biology All levels of life have systems of related parts. All levels of life have systems of related parts. A system is an organized group of interacting parts. A system is an organized group of interacting parts. A cell is a system of chemicals and processes. A cell is a system of chemicals and processes. A body system includes organs that interact. A body system includes organs that interact. An ecosystem includes living and nonliving things that interact. An ecosystem includes living and nonliving things that interact. Biologists study many different systems. Biologists study many different systems. DNA to ecosystems DNA to ecosystems

10. 1-2 Unifying Themes of Biology Structure and function are related in biology. Structure determines function. Proteins with different structures perform different functions. Heart muscle cells have a different structure and function than stomach muscle cells. Different species have different anatomical structures with different functions.

11. 1-2 Unifying Themes of Biology Organisms must maintain homeostasis to survive in diverse environments. Organisms must maintain homeostasis to survive in diverse environments. Homeostasis is the maintenance of constant internal conditions. Homeostasis is the maintenance of constant internal conditions. Sweating Sweating Heart rate Heart rate Sugar levels Sugar levels

12. 1-2 Unifying Themes of Biology Homeostasis is usually maintained through negative feedback. Homeostasis is usually maintained through negative feedback. Negative feedback systems return a condition to its normal (set) point. Negative feedback systems return a condition to its normal (set) point. Temperature Temperature Respiration Respiration Heart Rate Heart Rate

13. 1-2 Unifying Themes of Biology Behaviors and adaptations can help maintain homeostasis. Reptiles sun themselves Hogs roll in mud Blood flow in walrus

14. 1-2 Unifying Themes of Biology Evolution explains the unity and diversity of life. Evolution explains the unity and diversity of life. Evolution is the change in living things over time. Evolution is the change in living things over time. The genetic makeup of a population of a species changes. The genetic makeup of a population of a species changes. Evolution can occur through natural selection of adaptations. Evolution can occur through natural selection of adaptations. Adaptations are beneficial inherited traits that are passed to future generations. Adaptations are beneficial inherited traits that are passed to future generations.

15. 1-2 Unifying Themes of Biology Evolution accounts for both the diversity and the unity of life. Evolution accounts for both the diversity and the unity of life. Cells have similar structures and chemical processes Cells have similar structures and chemical processes However, they also perform different functions However, they also perform different functions Humans and bacteria have similar structures but perform different tasks as part of their lives Humans and bacteria have similar structures but perform different tasks as part of their lives

16. 1-3 Scientific Thinking and Processes Like all science, biology is a process of inquiry. Like all science, biology is a process of inquiry. Scientists make careful and systematic observations. Scientists make careful and systematic observations. Scientists record observations as data. Scientists record observations as data. Scientists form a hypothesis as a possible answer to a question. Scientists form a hypothesis as a possible answer to a question. Scientists test their hypotheses and analyze their data. Scientists test their hypotheses and analyze their data.

17. 1-3 Scientific Thinking and Processes Biologists use experiments to test hypotheses. Observational studies allow scientists to describe a phenomenon. Observing/watching Cameras Computers

18. 1-3 Scientific Thinking and Processes Observations provide data Observations provide data Data allows observations to be analyzed Data allows observations to be analyzed Quantitative Data – data that can be measured or counted Quantitative Data – data that can be measured or counted Qualitative Data – data that describes the characteristics or qualities of a situation or phenomenon Qualitative Data – data that describes the characteristics or qualities of a situation or phenomenon Observations also help generate hypotheses (hypothesis) Observations also help generate hypotheses (hypothesis) A hypothesis is a proposed explanation for a question (an educated guess). A hypothesis is a proposed explanation for a question (an educated guess). Specific and testable Specific and testable

19. 1-3 Scientific Thinking and Processes Experimental testing Experimental testing Experiments allow for testing of a hypothesis to see if it is valid Experiments allow for testing of a hypothesis to see if it is valid In science, usually testing one time is not enough In science, usually testing one time is not enough Validity and Reliability Validity and Reliability Statistics are used to evaluate the data Statistics are used to evaluate the data Nonsignificant – data shows a small or no effect so that the results may have happened by chance Nonsignificant – data shows a small or no effect so that the results may have happened by chance Statistically significant – data shows an effect that is not due to chance Statistically significant – data shows an effect that is not due to chance Probability – mathematical determination of significance Probability – mathematical determination of significance

20. 1-3 Scientific Thinking and Processes Experimental studies allow scientists to determine what causes a phenomenon. Experimental studies allow scientists to determine what causes a phenomenon. Independent variables are manipulated (x-axis) Independent variables are manipulated (x-axis) Dependent variables are observed and measured (y-axis) Dependent variables are observed and measured (y-axis) Constants are conditions that are kept the same. Constants are conditions that are kept the same. Controlled experiment Controlled experiment

21. 1-3 Scientific Thinking and Processes A theory explains a wide range of observations. A theory explains a wide range of observations. Theories explain a wide range of observations and experimental results. Theories explain a wide range of observations and experimental results. A theory is supported by a wide range of scientific evidence. A theory is supported by a wide range of scientific evidence. Theories can change based on new evidence. Theories can change based on new evidence. Humours vs. Germ Theory Humours vs. Germ Theory

22. 1-4 Biologists’ Tools and Technology Imaging technologies provide new views of life. Imaging technologies provide new views of life. A microscope provides an enlarged image of an object. A microscope provides an enlarged image of an object. Light microscopes (LM) Light microscopes (LM) 1500x 1500x Staining Staining

23. 1-4 Biologists’ Tools and Technology Imaging technologies provide new views of life. Electron microscopes (100,000x) Scanning electron microscope – cans the surface (3D image) Transmission electron microscope – beam passes through a slice

24. 1-4 Biologists’ Tools and Technology Imaging technology is used in medicine. Imaging technology is used in medicine. X-rays X-rays CT Scans CT Scans MRI MRI PET Scans PET Scans

25. 1-4 Biologists’ Tools and Technology Complex systems are modeled on computers. Computer models are used to study systems that cannot be studied directly. heart attacks effect of medicines on body movement of water molecules into/out of a cell spread of a disease through a population Computer models are used when experiments are not safe, ethical, or practical. Normal heartbeat Heart attack

26. 1-4 Biologists’ Tools and Technology The tools of molecular genetics give rise to new biological studies. The tools of molecular genetics give rise to new biological studies. Through our understanding of DNA, we can study genetics on a molecular level. Through our understanding of DNA, we can study genetics on a molecular level. Molecular genetics – the study and manipulation of DNA molecules Molecular genetics – the study and manipulation of DNA molecules Genomics – the study and comparison of genomes within/across species Genomics – the study and comparison of genomes within/across species

27. 1-5 Biology and Your Future Your health and the health of the environment depend on your knowledge of biology. Your health and the health of the environment depend on your knowledge of biology. Knowledge of biology helps you understand your health. Knowledge of biology helps you understand your health. food allergies food allergies potential effects of obesity potential effects of obesity

28. 1-5 Biology and Your Future Knowledge of Biology also helps understand Knowledge of Biology also helps understand Cancer Cancer Effects of alcohol, tobacco, and other drugs Effects of alcohol, tobacco, and other drugs Child development Child development

29. 1-5 Biology and Your Future Knowledge of biology can help you understand environmental issues. Interactions in ecosystems Pollution Biodiversity

30. 1-5 Biology and Your Future Biotechnology offers great promise but also raises many issues. Biotechnology offers great promise but also raises many issues. Biotechnology is the use and application of living things and biological processes. Biotechnology is the use and application of living things and biological processes. Making bread/beverages Making bread/beverages Medicine Medicine Agriculture Agriculture Forensic science Forensic science

31. 1-5 Biology and Your Future Biotechnology also helps us understand living things Biotechnology also helps us understand living things DNA testing in medicine and forensics DNA testing in medicine and forensics transgenic (genetically modified) crops transgenic (genetically modified) crops transgenic bacteria transgenic bacteria

32. 1-5 Biology and Your Future Questions are raised about the use of biotechnology. Questions are raised about the use of biotechnology. Safety of genetically modified crops Safety of genetically modified crops Spread of undesirable genes Spread of undesirable genes Decrease in biodiversity Decrease in biodiversity Ethical considerations Ethical considerations

33. 1-5 Biology and Your Future Biology presents many unanswered questions. Biology presents many unanswered questions. Over the past 50 years, biological knowledge has greatly increased. Over the past 50 years, biological knowledge has greatly increased. There are still many questions to answer in biology. There are still many questions to answer in biology. How are memories stored in the brain? How are memories stored in the brain? How do viruses mutate? How do viruses mutate? Does life exist on planets other than Earth? Does life exist on planets other than Earth?