Chapter 1- Invitation to Biology Scientific study of life Scientific study of life Lays the foundation for asking basic questions about life and the natural world Lays the foundation for asking basic questions about life and the natural world Why Study Biology? To learn how organisms are constructed, how they function, where they live, and what they do To learn how organisms are constructed, how they function, where they live, and what they do To help develop, modify, and refine ideas about life To help develop, modify, and refine ideas about life

Levels of Organization Fig. 1.2, p.4

Levels of Organization Fig. 1.2, p.4

Levels of Organization Fig. 1.2, p.4

Levels of Organization Fig. 1.2, p.4

Levels of Organization  Unicellular- single celled organism  Multicellular- many celled organism Fig. 1.2, p.5

Levels of Organization  Population- group of one species in area Fig. 1.2, p.5

Levels of Organization  Community- many species in one area  Ecosystem- community interacting with physical environment  Fig. 1.2, p.5

Levels of Organization  Biosphere- surface and atmosphere of earth Fig. 1.2, p.5

ALL LIVING THINGS… Require Energy  Energy = Capacity to do work  Metabolism = Reactions by which cells acquire and use energy to grow, survive, and reproduce ALL LIVING THINGS… Are Made of Cells  Are composed of the same substances from atoms to molecules to cells etc.

ALL LIVING THINGS… Sense and Respond  Organisms sense changes in their environment and make responses to them  Receptors detect specific forms of energy (stimuli)  Allows maintenance of homeostasis

ALL LIVING THINGS… Grow and Develop  Cell division increases the size of an organism.  The instructions from DNA allow cells to differentiate as the organism develops from egg to adulthood.

ALL LIVING THINGS… Reproduce  Have the capacity to reproduce based on instructions in DNA. This ability is not required for the survival of the individual, but must occur to continue the species.  Two types  Asexual Reproduction- offspring produced without use of sex cells  Sexual Reproduction- offspring produced by joining sex cells

ALL LIVING THINGS… Adapt/Evolve  Adaptations are traits that give an advantage in a certain environment.  Variation of individuals comes from mutations and sexual reproduction.  Evolution is when these changes areas passed down from generation to generation.

CLASSIFICATION & Binomial Nomenclature  Devised by Carolus Linnaeus  First name is genus (plural, genera) which helps to characterize the organism. Homo sapiens - genus is Homo Homo sapiens - genus is Homo  Second name is species within genus. Species characteristics are unique to that species. Homo sapiens – species is sapiens Homo sapiens – species is sapiens

Classification System For Humans… For Humans…  Domain- Eukarya  Kingdom- Animalia  Phylum- Chordata  Class- Mammalia  Order- Primata  Family- Hominidae  Genus- Homo  Species- Homo sapiens For Jaguars… For Jaguars…  Domain- Eukarya  Kingdom- Animalia  Phylum- Chordata  Class- Mammalia  Order- Carnivora  Family- Felidae  Genus- Panthera  Species- onca

3 Domains Fig. 1-7, p.8 Bacteria ArchaeaEukarya

Examples of Life’s Diversity Fig. 1-8, p.8 Bacteria Strep Throat- streptococcus Tuberculosis bacteria Archaea

Fig. 1-8c(2), p.9 Examples of Life’s Diversity Protists Fungi

Fig. 1-8c(10), p.9 Examples of Life’s Diversity Animals Plants

From 5 to 6 Kingdoms

 Single cells  No nucleus or membrane-bound organelles  Smaller, less complex  Ex: bacteria Prokaryotic Organisms Eukaryotic Organisms  Single- or multi-celled  Nucleus and other membrane-bound organelles  Larger, more complex  Ex: Animals, plants, fungus

Mutation: Source of Variation  Mutation = change in structure of DNA  Basis for the variation in heritable traits  Most are harmful Adaptive Trait / Adaptation  A trait that gives the individual an advantage in survival or reproduction, under a given set of circumstances

Evolution  Genetically based change in a line of descent over time  Population changes, not individuals

Natural Selection  Individuals vary in some heritable traits  Some forms of heritable traits are more adaptive  Natural selection is differences in survival and reproduction among individuals that vary in their traits  Adaptive forms of traits become more common than other forms

Figure 1.14

Scientific Method  Observe phenomenon  Develop hypotheses  Make predictions  Devise test of predictions  Carry out test and analyze results

Inductive Logic  Using observations and facts to arrive at generalizations or hypotheses  Observation: Eagles, swallows, and robins have feathers  Hypothesis: All birds have feathers

Deductive Logic  Drawing a specific conclusion based on a generalization Generalization - Birds have feathers Generalization - Birds have feathers Example - Eagles are birds Example - Eagles are birds Conclusion - Eagles have feathers Conclusion - Eagles have feathers

Role of Experiments  Used to study a phenomenon under known conditions  Allows you to predict what will happen if a hypothesis is not wrong  Can never prove a hypothesis 100% correct

Scientific Theory  A hypothesis that has been tested for its predictive power many times and has not yet been found incorrect; based on Evidence- facts or information holding an idea to be valid  Valid-q  Valid-quality of being logically or factually sound  Has wide-ranging explanatory power Darwin’s theory of evolution by natural selection Darwin’s theory of evolution by natural selection  Does not contain bias- favor of or against one thing

Law  Notes only that something happens, happens consistently and across the universe; usually simply stated; frequently can be stated mathematically.  Example: Newtons 2 nd Law: F = ma Newtons 2 nd Law: F = ma A body of mass (m) subject to a force (F) undergoes an acceleration (a) that has the same direction as the force and a magnitude that is directly proportional to the force and inversely proportional to the mass.A body of mass (m) subject to a force (F) undergoes an acceleration (a) that has the same direction as the force and a magnitude that is directly proportional to the force and inversely proportional to the mass.

What is pure and applied science?  Pure Science Answers questions about phenomena and mechanisms in the natural world. Answers questions about phenomena and mechanisms in the natural world. Why do you do it? Why do you do it? Because we wanted to know!Because we wanted to know! EX. Studying the ICE MAN EX. Studying the ICE MAN  Applied Science Application of scientific knowledge to practical problems. Application of scientific knowledge to practical problems. Why do you do it? Why do you do it? To fight disease, identify criminals, learn how to store hazardous wastes…etc.To fight disease, identify criminals, learn how to store hazardous wastes…etc.

Making Decisions in Science

GRAPHING TERMS  Positive Relationship- when both variables increase.  Negative Relationship- when the variables are inverse to one another.

Mathmatical terms