AnnouncementsBig Ideas Writing AssignmentExam 2Timeline of Life on EarthBacteriaArchaea23_BIO130_0324143/24/2014Bio 130 TR 12:40-1:55p AnnouncementsExam 2 is this ThursdayOffice hours this afternoon 657B DabneyBig Ideas Writing Assignment due April 15thBig Ideas Writing AssignmentYou are treating each Big Idea as a claim and providing evidence from the article to support it. SystemsExample for systems:1. Identify the system2. Tell how the systems are connected or interactStructure and FunctionExample of organisms’ Structure and Function:A leaf’s structure allows it to photosynthesize A cheetah’s tail allows it to balanceExamples of ecosystems’ Structure and Function:A food web’s trophic levels affect each otherEvolutionFor evolution, make sure to state the population and the trait that evolved and make sure to say if the process was selective or non-selectiveExam 2Remember for the exam to be able to describe natural selection and include all the important requirements. The material goes from Ecology through Climate Change.Timeline of Life on EarthThe formation of the solar system happened over 4570 million years ago. Primitive implies older,but everything on earth today is at the same evolutionary age as any other living organism. So bacteria are not more primitive than humans. Until recently, the main domains of life were defined as prokaryotes and eukaryotes. Now, based on their evolutionary morphology, they are grouped into three groups: Bacteria, Archaea, and EukaryotesBacteriaThe cell walls have peptidoglycan but the structure differs between gram positive and gram negative bacteria. Has no nucleus (prokaryotic), or membrane-bound organelles. Gram positiveAbsorbs stain turns purpleAffected by PenicillinGram negativeDoes not absorbs stain, pinkAffected by AminoglycanArchaeaHas no nucleus (prokaryotic). Much less is known about Archaea. The cell wall is not made of peptidoglycan. All single-cell (unicellular organisms). Phototroph use sunlight for energyChemotroph use chemical reactions for energyAutotrophs synthesize their own C-C from inorganic sources (Carbon-fixers)Heterotrophs absorb C-C from the environmentChemical reactionsUse light as an energy sourcePhototrophsChemotrophsInorganic molecules (ex. CO2)Organic sources (from