Tutorial One Biology the study of life Characteristics of life order the need for energy growth and development regulation of one s internal environment and evolutionary adaptation Natural Selection Evolution Evolution genetic changes of a population over time An example of an evolutionary change is a change in the coat color in mammals to better hide themselves in their natural environment N S population that becomes better adapted to its environment over time differential reproduction the fittest The organisms with the best genetics are most likely to procreate survival of Adaptation a trait that can help an organism survive in its current environment Common ancestor 3 7 billion yrs Example of Ev N S Evolution Canyon one side is exposed to extreme UV radiation causing the slope to be dry arid and covered with yellow brown grass the other side is not so the slope has dark rich soil with an abundance of healthy dark green vegetation Tutorial Two Water Fundamental to the existence of life polar slightly positive H side and slightly negative O side H bonds are the cause of water s special characteristics such as its Cohesion bonding to other water molecules Adhesion bonding to other surfaces High surface tension High specific heat it takes a lot of energy to raise the temp of water this causes water to be able to absorb and store energy efficiently helps stabilize a living organism s internal environment High heat of vapor resistant to phase changes Good solvent Covalent bonds have a sharing of electrons Electronegativity is the ability for an atom to pull electrons closer to it Amphipathic the ability of a molecule to have a charge on one side and no charge on the other Carbon Inorganic minerals water rocks Organic all living things contains C C s 4 valence electrons allows much structural versatility Anabolism building up Catabolism breaking down Hydrolysis splitting a molecule with the addition of water Condensation dehydration Synthesis joining molecules by removing water Carb mainly composed of C H O used for energy storage and structural support cellulose Single unit monosaccharide Multiple monosaccharides are joined together by D S poly disaccharides Glycogen is a polysaccharide Lipids include steroids phospholipids amphipathic and triacylglycerols main function is energy storage Occurs when a person s hemoglobin protein structure is incorrect Saturated all single bonds Unsaturated at least one double bond Proteins Basic monomer amino acid 20 Peptide bonds polypeptide Functionally structurally diverse Sickle Cell Anemia Nucleic acids include DNA and RNA DNA adenine thymine guanine and cytosine RNA adenine uracil guanine and cytosine Held together by H bonding Tutorial Three Universe 13 7 billion yrs old Solar system 4 55 billion years ago Early Earth little amt of O atmosphere was reducing which means it helped form more complex molecules Autotrophs make their own food Heterotrophs have to consume their nutrients Plate tectonics when the Earth s crust moves in large plates relative to each other Continental Drift the continents are constantly moving because of the plate tectonics Pangaea the super continent when all of the plates were joined about 250 mill yrs ago Precambrian oldest Paleozoic Mesozoic Cenozoic Best source of fossils are sedimentary rock which is formed in layers as minerals settle out of the water Carbon 14 Radiocarbon Dating the process by which you can estimate how old something is by measuring the amount of carbon found in the substance Dendrochronology dating trees by observing its rings Life is divided into 3 major domains Bacteria prokaryotes Archaea prokaryotes Eukarya eukaryotes Tutorial Four No membrane bound organelles Smaller than eukaryotes Shapes 1 Coccus ball 2 Bacillus rod 3 Spirillum spiral Prokaryotes Bacteria most successful group of life on Earth essential for ecological balance cause of many human diseases Archaea a prokaryotic group that have more eukaryotic features than prokaryotic Domains Archaea Bacteria and Eukarya there are some combinations of the three archaebacteria eubacteria and eukaryotes Life emerged 3 5 bya Extremophiles some archaea can live in harsh environments such as a hot spring ice or acidic pond 3 Factors that help them grow quickly Little genetic material Simple physical features Reproduce by binary fission chromosomes replicate then one cell splits in half to create two new cells asexual DNA in prokaryotes nucleoid Extrachromosomal DNA plasmids 3 ways a prokaryote can transfer genes Transformation getting genes from the environment DNA could have been left behind by other bacteria pathogenic to non pathogenic Conjugation a physical link forms when a male pilus containing the F factor fertility factor plasmid joins with a female that has no F factor then end result is the female turns into an F male Transduction an exchange of DNA due to viruses that infect bacteria phages destroys the host cell then moves on the next one carrying both its own DNA and its previous host s DNA Tutorial Five Most prokaryotes have cell walls but they are different than those of plants bacterial cell walls contain peptidoglycan polymer made up of sugar and polypeptides To figure out which type of bacteria it is you can use a method called Gram s stain which identifies the bacteria by the amount of peptidoglycan in its cell wall A lot of peptidoglycan less complex cell walls gram Little peptidoglycan more complex cell walls gram also have another outer membrane that is attached by lipopolysaccharides These lipopolysaccharides can be toxic this also means they are more resilient to antibiotics To help fight infection many bacteria have adapted and formed an additional layer outside of the cell wall called a capsule it is sticky so bacteria are able to adhere together and it also individually better protects them Most common way that bacteria get around is by using flagellum tail Clockwise rotation tumbling randomly away from each other Counterclockwise move together and begin to clump more organized Taxis moving towards or away from a stimulus Chemotaxis moving towards a chemical source such as carbon Chemotaxis moving away from a chemical source that could be poisonous Phototaxis moving towards the light Phototaxis moving away from light Some prokaryotes use carbon as an energy source mainly through sugars and carbohydrates Few can even use oil as a food source this means that bioremediation can occur cleaning up oil spills with the