EEMB 136 Lecture Notes - Lecture 5: Ribosomal Rna, Electron Donor, Chemotroph
15 Nov 2017
School
Department
Course
Professor
Document Summary
Have dna, rna, protein that are presented in all organism-> start conducting the tree. Energy from chemical reactions known as redox reactions. Ribosomal rna (rrna) is homologous in all life, functionally constrained but variable (so the sequences should be similar enough to compare but different enough to record divergent histories). Characteristics: metabolically simple, morphologically diverse, widespread, but few in extreme environments. Includes geologically important group, the cyanobacteria (photosynthetic bacteria, primary source of oxygen on earth) Indicate the general distribution of (a) prokaryotes and (b) eukaryotes on a plot of metabolic vs. morphological diversity. Need prokaryotes to split the triple bond of nitrogen gas in the nitrogen cycle and to aid in disgestion. Light energy = phototroph (photo = light; -troph = to feed) Two types of chemotrophs depending on the type of fuel that is used: Carbon source: inorganic (co2, co32-, hco3-, h2co3) = autotroph, inorganic (co2, co32-, hco3-, h2co3) = autotroph, organic = heterotroph.
