Biology Chapter 1 The Science of Biology Today
Biology Chapter 1 The Science of Biology
Today you will learn about: • Observations • Inferences • The scientific process – Hypothesis – Controlled experiment • Variables in experiments – Theory • • Characteristics of Living Things Levels of Organization
Define the following terms. • Science – organized way of using evidence to learn about the natural world; also, the body of knowledge that scientists have built up after years of using this process • Observation – use of one or more of the senses—sight, hearing, touch, smell, and sometimes taste—to gather information • Data – evidence; information gathered from observations • Inference – logical interpretation based on prior knowledge and experience • Hypothesis – possible explanation for a set of observations or possible answer to a scientific question
What are two types of Observations? • Qualitative observations – involve characteristics that cannot be easily measured or counted, such as color or texture. • Quantitative observations – involve numbers, for example, counting or measuring objects.
Take a minute to write 2 qualitative observations and 2 quantitative observations. Make an inference based on your observations.
Making Inferences
Scientific Method • Stating the problem – Identify a problem to be solved, come up with a scientific question • Hypothesis – A possible answer to a scientific question • Controlled Experiment – An experiment set up to test the hypothesis created. Only one variable should be tested at a time. • Record analyze data – Using graphs, diagrams, computers • Conclusion – Draw a conclusion based on the data collected. Was your hypothesis correct? If so, how can you test it further. • Publishing and Repeating Investigations – The results of the experiment should be published for other scientists to test.
A Controlled Experiment • Whenever possible, a hypothesis should be tested by an experiment in which only one variable is changed at a time. All other variables should be kept unchanged, or controlled. • What are the two variables in a controlled experiment? • Manipulated (Independent) Variable – Is the variable which is deliberately changed • Responding (Dependant) Variable – Is the variable which changes in response to the manipulated variable
Avoiding Bias – The way that science is applied in society can be affected by bias, which is a particular preference or point of view that is personal, rather than scientific. – Science aims to be objective, but scientists are human, too. Sometimes scientific data can be misinterpreted or misapplied by scientists who want to prove a particular point. – Recommendations made by scientists with personal biases may or may not be in the public interest. But if enough of us understand science, we can help make certain that science is applied in ways that benefit humanity.
How a theory develops. In science, the word theory applies to a well -tested explanation that unifies a broad range of observations.
8 Characteristics of Living Things 1. Living things are made up of units called cells.
2. Living things reproduce. • Sexual Reproduction • Asexual Reproduction
3. Living things are based on a universal genetic code.
4. Living things grow and develop.
5. Living things obtain and use materials and energy.
6. Living things respond to their environment.
7. Living things maintain a stable internal environment. • Homeostasis – process by which organisms maintain a relatively stable internal environment
8. Taken as a group, living things change over time.
Levels of Organization
Homework Biology Textbook: • Read pages 4 -25 and complete the following questions. – p. 15 #’s 1. b, 2. a, 2. b, and 4. c – p. 25 #’s 1. a, 2. b, 3. a, and 4. a
- Slides: 20
