Pitt BIOSC 1000 - Exam 1 Study Guide (53 pages)

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BIOSC 1000 Exam 1 Study Guide Lectures 1 7 Lecture 1 August 26 1 Foundations of Biochemistry Many scientific fields attribute to and overlap with biochemistry o Cell biology o Genetics o Chemistry o Physics o Evolution Some characteristics of Living Organisms o Highly complex structures with amazing microscopic organization o Extract usable energy from food or the environment to do mechanical and metabolic work o Defined and regulated functions o Responsive to environment o Reproduction like begets like o Evolves overtime Cellular Foundations o Three domains of Life Bacteria single celled Inhabit soils surface waters tissues of decaying living organisms Archaea single celled Extreme environments salt lakes hot springs acidic bogs ocean depths Eukarya o Evolved from Archaea Differences at the cellular level Bacterial and archaeal ribosomes are smaller than eukaryotic ribosomes but serve the same function of protein synthesis from an RNA message o Common structures of bacterial and archaeal cells Cells are 2 microns by 1 micron in size Nucleiod Pili Flagella Cell envelope Eukarya cells 5 100 microns nuclear envelope organelles Sources of Energy Phototrophs sunlight Chemotrophs oxidation of chemical fuels Further division Autotrophs directly from CO2 Heterotrophs require organic nutrients made by other organisms Examples Humans chemoheterotrophs Cyanobacteria photoautotrophs Chemical Foundations o Biomolecules achieve a high degree of variation while utilizing a modest number of low AMU elements Small atoms form stronger chemical bonds Most of the dry mass of any cell is composed of H C N O several other elements are used by all cells in smaller amounts Some trace elements are only used by a few life forms o The chemistry of biological molecules is centered on carbon which is weakly reactive Reactivity is achieved by functional group substitution associated with carbon Cellular Foundations Basic Biochemical Building Blocks o Amino acids are the building blocks of