Campbell Biology Chapter 1 PDF

Campbell Biology Chapter 1 https://xkcd.com/2307  Key Concepts The study of life reveals common themes. The Core Theme: Evolution accounts for the unity and diversity of life. In studying nature, scientists make observations and then form and test hypotheses. T...

Campbell Biology Chapter 1 https://xkcd.com/2307  Key Concepts The study of life reveals common themes. The Core Theme: Evolution accounts for the unity and diversity of life. In studying nature, scientists make observations and then form and test hypotheses. Themes in the Study of Life THINK PAIR SHARE Describe the properties of living organisms What is the definition of life?  Are Viruses Alive? YES NO MAYBE?  Can Viruses Evolve? YES NO MAYBE? New Properties Emerge at Each Level in the Biological Hierarchy Life can be studied at different levels, from molecules to entire living planet Study of life can therefore be divided into different levels of biological organization through a strategy called reductionism Reductionism refers to reducing complex systems to simpler components that are more manageable to study Levels of Biological Organization Figure 1.3 Exploring Levels of Biological Organization. How can we understand the organization of life?  Evolution: “The process of change Evolution Explains: that has transformed life Adaptations to the environment on Earth from its earliest Geographical distribution beginnings to the Origins and relationships diversity of organisms Similarities and differences living today” Campbell Biology Diversity textbook Evolutionary mechanisms account for the unity and diversity of all species on Earth  Macroevolution: Evolutionary Evolutionchange above the species level “The process of change that has transformed life e.g.from on Earth origin of new species or mass extinction its earliest events beginnings to the diversity of organisms living today” Campbell textbook  Microevolution: Evolutionchange below the species level Evolutionary “The process of change that has transformed life on EarthAfrom change in the genetic composition of a its earliest beginnings population to the from generation to generation diversity of organisms living today” Campbell textbook  Classifying the Diversity of Life Approximately 1.8 million species have been identified and named to date Thousands more identified each year Estimates of total number of species that exist range from 10 million to over 100 million Grouping Species: The Basic Idea Taxonomy - branch of biology that names and classifies species into groups of increasing breadth Domains, followed by kingdoms, are the broadest units of classification Organisms are divided into three domains: Organization of life Bacteria Archaea Eukarya Archaea (all unicellular, no nucleus or mitochondria) Organization of life – how we name species  Evolution is not goal oriented Youtube: Stated Clearly What is Evolution? Great Moments in Evolution Scientific method  Is evolution a hypothesis, a theory or a law? Youtube: It’s Okay to be Smart Fact/Theory/Hypothesis/Law xkcd.com Scientific method DOES NOT EQUAL Experiments https://www.khanacademy.org/science/biology/intro-to- biology/science-of-biology/a/experiments-and-observations Much of our understanding of evolution comes from observations. H. Zell, CC BY-SA 3.0 https://www.khanacademy.org/science/biology/her/evolution- and-natural-selection/a/lines-of-evidence-for-evolution However, there is also lots of cool experimental evolution studies! Fritzflohrreynolds CC BY-SA 3.0