Chapter 1_Hill_edit.pptx

Chapter 1 Human Biology, Science, and Society Human Biology: Concepts & Current Issues - Johnson (8th Ed.)  What is Life? Life is recognized by what living things do or by the characteristics of living...

Chapter 1 Human Biology, Science, and Society Human Biology: Concepts & Current Issues - Johnson (8th Ed.)  What is Life? Life is recognized by what living things do or by the characteristics of living things Some Properties of Life. Campbell Biology, Reece et al., 10th Ed. (Fig.1-2) © 2017 Pearson Education, Inc.  Question? The ability to grow and reproduce is a characteristic of life. The above statement is ____________. True False Figure 1.4 Living things are grouped according to characteristics Protista Animalia Fungi Plantae Kingdoms (Protozoans, (Animals) (Fungi) (Plants) Eubacteria Archaebacteria algae, and slime molds) (Bacteria) (Primitive bacteria) BACTERIA ARCHAEA EUKARYA DOMAINS Earliest organisms © 2017 Pearson Education, Inc.  Fundamental criteria used for classification Presence or absence of a nucleus Domain Bacteria and domain Archaea lack a membrane-bound nucleus Domain Eukarya has a membrane-bound nucleus Number of cells Unicellular Multicellular Type of nutrition/metabolism Producer Consumer © 2017 Pearson Education, Inc.  Domain Eukarya includes four kingdoms The Three Domains of Life. Campbell Biology, Reece et al., 10th Ed. (Fig.1-13) © 2017 Pearson Education, Inc.  Ended here on 1/17/2023 © 2017 Pearson Education, Inc.  Human biology can be studied on any level of biological organization Atom and molecule Cell Tissue Lo rga o w n Organ es iza t ti Organ system to o hi gh Organism n es t Population le ve Community lo f Ecosystem Biosphere © 2017 Pearson Education, Inc.  Figure 1.6 Levels of organization in human biology. Living Organism Population organisms Organ system have specific order both at Atom the individual Molecule and the group Organ levels Tissue Cell Community All the living organisms in a specific area, along with all of the nonliving factors with which they interact, Ecosystem form an ecosystem Biosphere © 2017 Pearson Education, Inc. Defining Features of Humans Bipedalism: able to stand upright and walk on two legs Opposable thumbs: able to grasp objects between thumb and tips of fingers Large brain: relative to body size; helpful for tool use, language, social interaction Capacity for language: complex spoken and written language Chimpanzees are the closest living relatives of humans. The divergence between human and chimpanzee ancestors dates to approximately 6.5– 7.5 million years ago. Human Chimpanzee Arboreal: inhabiting or frequenting trees  Scientific Process The word science is derived from a Latin verb meaning “to know” Science is a way of knowing, based on inquiry Science is therefore developed from our curiosity about ourselves and the world around us The way scientific knowledge is acquired is called the scientific method © 2017 Pearson Education, Inc.  Scientific Process There are two main scientific approaches: Discovery science is mostly about describing nature (i.e., observational science) Hypothesis-driven science is mostly about explaining nature (i.e., experimental science) © 2017 Pearson Education, Inc.  Discovery Science Careful observation and measurement: the raw data for discovery science. Campbell Essential Biology with Physiology, Simon et al., 5th Ed. (Fig 1.2) Recording the observations of chimpanzee behavior is an example of discovery science (observation science)  Hypothesis-Driven Science Most modern scientific investigations can be described as hypothesis-driven science A hypothesis is a tentative answer to a question - an explanation on trial A hypothesis must be testable Once a hypothesis is formed, an investigator can use logic to test it Although we don’t think of it in those terms, we use hypotheses in solving everyday problems, like figuring out why a TV remote fails © 2017 Pearson Education, Inc.  A hypothesis is tested by performing an experiment to see whether results are as predicted…… The steps involved in scientific method – o Observe and generalize o Formulate a hypothesis o Make a testable prediction o Experiment or observe o Modify hypothesis if needed and Applying the scientific method to a common problem. Campbell Essential Biology with Physiology, Simon et al., 5 th Ed. (Fig 1.3) repeat © 2017 Pearson Education, Inc.  Figure 1.7 the scientific method. Inductive reasoning draws ve reasoning conclusions I n d u c ti through the logical process of induction ve reasoning I n d u c ti uc tive reasoning Ind Formulate Modify Modify Direction of Experiment Experiment Observe a hypothesis hypothesis increasing or or and hypothesis as as confidence observe observe generalize necessary necessary in and repeat and repeat hypothesis steps steps 3 and 4 3 and 4 ve u cti ing d D e as o n ng Make a testable re ni prediction a so e re uc tiv ng Ded ni o Make a testable e as prediction er tiv uc D ed Make a testable prediction Deductive reasoning uses general grounds to make © 2017 Pearson Education, Inc. specific predictions  Question? What step in the scientific method involves making a tentative statement that explains an observation or answers a question? 1. Observe and generalize 2. Form a testable prediction 3. Form a hypothesis 4. Perform an experiment or conduct observations Chapter 1 1.3 Science is both a body of knowledge and a process Designing and conducting the experiment  Designing and Conducting the Experiment Experiment A carefully planned and executed manipulation of the natural world to test your prediction In a controlled experiment, there are 2 designated groups Experimental group Control group Each group receiving the same treatment, except that the control group lacks ‘the factor’ that is being tested © 2017 Pearson Education, Inc. Designing and conducting the experiment An independent variable is the variable that in manipulated (i.e., the dosage of Drug X). Plotted on the x axis of a graph. A dependent variable is one that depends on an independent variable (i.e., blood pressure). Plotted on the y axis of a graph. Blood pressure (mm Hg) 0 10 Dosage of drug X (mg/day)  Hypothesis: Drug X reduces blood pressure in patients with high blood pressure. Prediction 10 mg/day of drug X will reduce blood pressure in adult male and female patients with blood pressure in the range of from 140/90 up to 159/99 mm Hg. The subjects are randomly assigned to the two groups. The control group is given a placebo.  Record data Compare the results to the predictions The hypothesis either receives support or it is falsified Blood pressure (mm Hg) 0 10 Dosage of drug X (mg/day) In a blind or blinded experiment, information which may influence the participants of the experiment is withheld. In a “double-blind” experiment the person giving the drugs does not know which group is which. May need to do more experiments to determine safely and efficacy of the drug for different groups of patients. Making Findings Known Findings are disseminated in peer-reviewed journals Experts must approve articles before publication Results are assumed to be valid only for conditions under which experiment was done A researcher tries to test the hypothesis that “exercise helps people sleep better” with the following study: He asks 50 regular joggers and 50 non-joggers how well they sleep at night. What are some problems with this experiment?  Question? Which statement is a scientific hypothesis? 1. Rock music is better than classical music. 2. Garden gnomes make strawberries grow larger. 3. Buying recycled paper is an acceptable practice. 4. Increasing dietary fiber decreases colon cancer risk.  Ended here on 1/19/2024 © 2017 Pearson Education, Inc.  Theory A scientific theory is much broader in scope than a hypothesis A well-tested hypothesis becomes a theory A theory is the highest status that any hypothesis can achieve For a hypothesis to become a theory it must be broad be extensively tested be supported over time explain a broad range of facts have a high degree of reliability Theories may be refuted in the future © 2017 Pearson Education, Inc. Chapter 1 1.4 Sources of scientific information vary is style and quality Sources of Scientific Information Vary in Style and Quality Peer-reviewed journals Nature Journal of the American Medical Association Science magazines and nonfiction books National Geographic The Smithsonian Scientific American General interest news magazines, daily newspapers Internet National Institute of Health Centers for Disease Control and Prevention American Cancer Society American Heart Association Chapter 1 1.5 Learning to be a critical thinker Learning to Be a Critical Thinker Become a skeptic Who says that a particular statement is true? Are they qualified? What evidence is presented? Is there a monetary motivation behind the claims? Learning to Be a Critical Thinker Learn how to read graphs Learning to Be a Critical Thinker Appreciate the value of statistics Distinguish anecdotes from scientific evidence Learn to distinguish results from conclusions Understand the differences between correlation and causation Drownings Ice cream sales  The Role of Science in Society Science improves technology and the human condition Science has limits Science helps us to make informed choices © 2017 Pearson Education, Inc.  Question? “The scientific method can be used to address all questions”. Is this statement true or false? True False  Review Questions 1. What are the 7 properties of life? 2. What are the 3 domains of life? In which domain we humans do belong? 3. What are the kingdoms of Eukarya? 4. What are the fundamental criteria used for classification? 5. What are the different levels of biological organization? 6. What is an ecosystem? 7. What are the differences between discovery science (also called descriptive science) and hypothesis-based science? 8. What are the steps involved in a scientific method? 9. What is the difference between an experimental  Ended here on 1/22/2024 © 2017 Pearson Education, Inc. To which of the following domains of life do humans belong? a. Archaea b. Bacteria c. Eukarya d. Animalia e. Mammalia To which of the following domains do unicellular organisms that lack nuclei belong? a. Eukarya b. Archaea c. Bacteria d. Both Archaea and Bacteria e. Both Eukarya and Archaea Which of the following is used when developing a hypothesis? a. observations b. inductive reasoning c. controlled experiments d. both observation and inductive reasoning An acceptable scientific hypothesis a. can be tested b. can be proven true c. can be proven false d. both (a) and (c) Which of the following lists the steps of the scientific method in order? a. observation, prediction, experimentation, hypothesis development b. hypothesis development, observation, experimentation, prediction c. prediction, hypothesis development, experimentation, observation d. observation, hypothesis development, prediction, experimentation