Biology 100/101
Lecture 1:
Introduction to Biology (Print version)

Expectations

Announcements &
Assignments

Lecture Objectives

What is Biology?
What is Life?

What is Science?

Science as a Way
of Knowing the
Natural World

Lecture Syllabus

IB 100/101 Home Page

Expectations and
Assumptions for Lecture Class

  • You can expect to have a chance to talk at certain times during lecture.

  • We will expect you to listen when someone else has the floor during lecture.

  • You can expect us to end lecture a few minutes early to give you time to get to your next class - or the coffee shop.

  • We will expect you to wait to pack up books & papers and put armchair desktops down until we finish the lecture.

  • You can expect to have an organizational outline with objectives and a specific reading assignment on the www prior to lecture.

  • We assume that you will attend all lectures and arrive on time.

  • We assume you have the ability to understand the fundamental concepts of modern biology.

  • You can expect all of us to help you understand those concepts.

Announcements

Text readings in Life by Ricki Lewis, et. al.

Chapter 1 (What is Life?)

"Testing Your Knowledge" questions

Pages 14-15, Questions 1, 3, 6, and 7

These questions are not required assignments.

"Thinking Scientifically" questions:

Page 15, Question 2

These questions are not required assignments.

Answers to many of these questions can be found on the Text On-Line Learning Center. Select "Student Edition" from the left hand menu, select the text chapter you want, and finally, select either "Testing Your Knowledge" or "Thinking Scientifically". Links to answers can be found on these pages.

You may also ask questions and see answers to your classmates' questions in Web Crossing in the "Talk to Jim, Ross, and Ed" discussion.

Lecture Objectives:

After studying this material you should be able to:

  1. Define the term "Biology."

  2. List and understand the combination of characteristics that distinguishes the living from the nonliving.

  3. Outline and describe the logic behind the basic steps of the scientific method.

  4. Explain what is meant by the phrase "science as a way of knowing the natural world."

Key Terms:

biology life prediction
adapt (v.) vs
adaptation (n.)		 hypothesis homeostasis
scientific method theory metabolism

What is Biology?

The study of the living world.

Modern biology encompasses all levels of organization and interaction:

  • among organic molecules
  • among organelles within a cell
  • among cells in an organ
  • among the organ systems in an organism
  • between organisms and the abiotic environment
  • among individuals in a population
  • among species in a biological community

Knowing the facts of biology without an understanding of the relationships among these levels of organization is insufficient to understand the biological world.

What is Life?

How do I know that you are living?

Life is defined in terms of qualities that the living uniquely share:

  • Life is organized
    • in sequences of increasing complexity (structures within structures)
    • the basic unit of life is the cell
    • levels of biological organization are hierarchical from cells - organisms - communities - biosphere
  • Life requires energy
    • the natural tendency of matter is towards disorder (i.e., entropy or randomness)
    • living systems acquire and use energy to maintain their highly organized state
    • metabolism: the biochemical reactions that acquire and use energy
  • Living things must maintain an internal constancy
    • this requires a separation from the non-living world
    • for metabolic processes to function normally, living things need to keep themselves stable in temperature, moisture level, chemistry, etc.
    • homeostasis: the ability to maintain internal constancy (i.e., to stay the same)
  • Living things grow, develop, and reproduce
    • vital if a population of organisms is to survive more than one generation
    • "Instructions" for growth and development are encoded in genes
  • Living things react to environmental change - Irritibility - (an individual reacts to its environment)
    • reaction may be immediate as in a reaction to extreme heat, or longer as in a change in leaf color in response to day length, but certainly within the lifetime of the individual.
    • behavior - move towards or away from stimuli
    • change in metabolism
    • change in development

  • Living things adapt (evolutionary change in a population over many generations)
    • an inherited characteristic or behavior enables an individual to live and reproduce with greater success than other members of their population in a given environment
    • these adaptations/modifications become more frequent in the population over several generations

What is Science?

Science is a process for answering our questions about the natural world.

    Lecture Activity

    • Get together with 1 or 2 other people near you.

    • Write down one observation concerning the male and female pheasants on the screen.

      • Male and female ring-necked pheasants

    • Write down a hypothesis that EXPLAINS why the different sexes of pheasant look different.

    • Suggest a means of TESTING your hypothesis

Formalizing the scientific process

The scientific method of investigation involves making a series of inquiries by observing, questioning, reasoning, predicting, testing, interpreting, and concluding. However, because these inquiries spawn new ideas and raise new questions, the scientific method is a cycle of inquiry, not a simple linear process of investigation.

Steps in the cycle:

  • Make observations, ask questions, and consult prior knowledge

  • After synthesizing this information, formulate a hypothesis - a tentative EXPLANATION of the observed facts (i.e., this is how I think the natural world works)

  • Make a prediction based on the hypothesis. The prediction is often phrased in conjunction with the hypothesis as an "If........then....." statement.

    • IF - state your hypothesis- THEN - state your prediction

    • NOTE that I am asking you to separate the hypothesis from the prediction. Think of the hypothesis as an explanation of an observed phenomenon.

  • Design an experiment or observation to test the hypothesis

    • controlled experiments can be done in a laboratory or the "field"

    • experiments can be purely observational

    • experiments can be conducted using computer models

  • Collect and interpret data

  • Draw conclusions
    -these conclusions either refute or support the hypothesis

  • Conclusions and further observations will probably suggest other questions, hypotheses, and experiments

Science as a Way of Knowing the Natural World:

  • A scientist believes that the natural world is a physical reality, but that we can only construct a conceptual view of that reality based upon observation and experimentation.

  • Each of us has our own view of the natural world that is viewed through the lens of our previous experience and knowledge.

  • Science strives to be objective, and is founded in the belief that events can be explained fully by natural causes. Conversely, explanations based in supernatural causes are not considered to be scientific. Rocks of Ages: Science and Religion in the Fullness of Life, By Steven Jay Gould

  • Scientific explanations of phenomena observed in the natural world are called hypotheses (singular: hypothesis).

  • Scientific hypotheses must be testable and falsifiable. If the hypothesis is incorrect it can be tested by experimentation and/or observation and proved to be false.

  • Experimentation and observations can increase our confidence that a hypothesis is a correct explanation of a phenomenon, but can never absolutely prove a hypothesis to be true.

  • Once a hypothesis has been supported by many experiments and/or observations it is considered by the community of scientists to be a theory. (Note that this is very different from the common use of the word, meaning an opinion or a guess.)

  • The conclusions of science are subject to change. New studies, which might utilize new techniques and equipment, may produce new information that leads to the conclusion that previously accepted theories need to be modified or changed entirely.

  • Great science is replaced by greater science.