Introduction to Biology Studying Life’s Diversity and Intricate Processes

What is this? Is it Alive?

Biological Inquiry Bio = of living things What are the Characteristics of Living Things?

What are common characteristics of living things? Properties of Life organization involving cells energy use and metabolism response to environmental changes regulation and homeostasis growth and development reproduction biological evolution

Organizational Hierarchy of Life Most Complex Least Complex biosphere inhabitable regions of earth ecosystem coral reef (living + nonliving) community coral reef populations population school of fish organism fish organ system nervous system organ brain tissue nervous tissue cell neuron organelle nucleus macromolecule DNA molecule nucleotide atom nitrogen sub-atomic particles protons, neutrons, electrons

Concept: Cells are an Organism’s Basic Units of Structure and Function. Two types of cells Prokaryotic Archaea and Bacteria few internal membranes no membrane-bound nucleus Eukaryotic Protists, Fungi, Animals, Plants extensive internal membranes membrane-bound nucleus organization

Concept: Structure and Function are Correlated at all Levels of Biological Organization. How is red blood cell structure suited to its function of carrying oxygen? organization

Energy Use and Metabolism Energy = ability to do work Energy conversion = change of one form of energy to another Metabolism = sum of chemical reactions in an organism Heterotrophic: other feeder taking in organic molecules produced by other organisms Autotrophic: self-feeder photosynthesis = using the energy of the sun to produce organic molecules

reproduction regulation Concept: The Continuity of Life is Based on Heritable Information in DNA. The molecule of heredity = DNA = deoxyribonucleic acid reproduction regulation

growth and development Concept: The Continuity of Life is Based on Heritable Information in DNA. Growth = increase in size Development = change in characteristics growth and development

regulation and homeostasis response to environmental changes Living things maintain homeostasis = a relatively stable internal condition regulation and homeostasis response to environmental changes

Concept: Evolution Accounts for the Unity and Diversity of Life Natural Selection leads to a change in the genetic characteristics of a population  evolution Adaptation = characteristic that promotes survival and reproduction

How Do Biologists Study Living Things? Hypothesis-based Science State the Problem Ask Questions or make Observations Formulate an Hypothesis: tentative answer to well-framed question Make Predictions based on hypothesis Test Predictions by Conducting Experiments Analyze experimental data Determine whether data supports hypothesis You Tube video on Paramecium contractile vacuole

How Do Biologists Study Living Things? A good hypothesis is Testable experiments can be designed to test predictions from the hypothesis experimental results must be repeatable Falsifiable allows scientists to eliminate alternative hypotheses

How Do Biologists Study Living Things? Testing hypotheses Controlled Experiment test designed to determine the effect of one factor while keeping all other factors constant experimental = sample treated to test for effect of the factor being studied control = sample treated like experimental in all ways EXCEPT for the factor being studied

How Do Biologists Study Living Things? Supported Hypotheses Theory = broad explanation of a natural phenomenon that has been supported by a large body of evidence Principle or Law = theory that has been supported over a long period of time Cell Principle All living things are composed of cells and cell products; all cells come from pre-existing cells. Principle of Evolution Law of Gravity