Introduction: Themes in the Study of Life Chapter 1

What is Life? Evolutionary adaptation

Emergent Properties Due to the arrangement and interactions of parts as complexity increases Each property emerges from new evolutionary novelties that were not present at simpler levels of organization

Levels of Organization

Exchange of Matter and Energy Ecosystem dynamics 2 processes Nutrient cycling One way flow of energy Energy conversion- one of energy is converted to another for use in moving, growing, reproducing…

Relationship of structure to function Form fits function Analyzing a biological structure gives an idea about its function Ex. Leaf Knowing the function of something gives an idea about its construction Ex. Bird wing

Form Fits Function

Cells: basic units of structure and function Prokaryotic cell typically bacteria and archaea no nucleus to enclose DNA no organelles Eukaryotic cell found in all other living organisms Nucleus DNA organized into chromosomes membrane bound organelles

Continuity of Life DNA structure and function Controls development and maintenance of entire organism Molecular structure of DNA accounts for its ability to store information Genes control protein production

Regulation Feedback mechanisms Positive feedback-product stimulates an enzyme in the reaction sequence, increasing the rate of production of the product

Regulation Negative feedback-accumulation of a final product inhibits an earlier enzyme in the sequence of reaction, slowing down the reaction

Evolution: Core Theme Accounts for the unity and diversity of life Organizing the diversity of life Grouped based on similarities Domains, Kingdoms, Phyla, etc.

Three Domains Domain Bacteria Most diverse and widespread prokaryotes Multiple kingdoms

Three Domains Domain Archaea Prokaryotes living in extreme environments Ex: salty lakes, boiling hot springs Multiple kingdoms

Three Domains Domain Eukarya Protists Multiple kingdoms-Fungi, Plantae, Animalia Unicellular eukaryotes and simple multicellular relatives

Three Domains Domain Eukarya Kingdom Fungi Absorbs nutrients from their surroundings

Three Domains Domain Eukarya Kingdom Plantae Multicellular eukaryotes that carry out photosynthesis

Three Domains Domain Eukarya Kingdom Animalia Multicellular eukaryotes that ingest other organisms

Evolution Charles Darwin and Natural Selection Descent with modification Adaptive radiation of finches on the Galapagos Islands

Inquiry Discovery Science Types of Data Inductive reasoning Describes natural structures and processes as accurately as possible through careful observation and analysis of data Types of Data Qualitative-descriptions Quantitative-measurements Inductive reasoning Derive generalizations from specific observations

Inquiry Hypothesis-Based Science Hypothesis-tentative answer to a well framed question If-Then format Deductive reasoning-general premise leads to specific results if the premise is true

Hypothesis Must be testable Must be falsifiable Check validity of the idea Must be falsifiable Must be some observation or experiment that could reveal if an idea is not true

Controlled experiments Experimental and control groups differ in only one factor Observations and experimental results must be repeatable

Theory Much broader in scope than a hypothesis General enough to spin off new specific hypotheses to be tested Supported by a greater body of evidence than a hypothesis

Science, technology and society Cooperation and competition in the scientific culture Science and technology are associated Technology often results from scientific discoveries Scientific discoveries often emerge from the development of new technologies

Science, technology and society The microscope led to an understanding of the cellular basis of life Watson and Crick’s discovery of DNA structure led to technological breakthroughs.