BIOL 1002 Exam 1 notes Chapter 18 Systematics Seeking Order Amidst Diversity Viruses aren t living things because they can t replicate on their own they enter cells force them to replicate Homo sapiens is a unified way to classify people Taxonomy is the branch of biology concerned with naming and classifying The 3 domains and the kingdoms within them each have observably different attributes that define them Bacteria Archaea Protista Fungi Plantae and Animalia Eukarya 50 100 trillion cells make up your bodies they all come from other cells mitosis Taxonomic categories The organization of taxonomic grouping arranges organisms in sets Each set is then grouped with other sets into a larger set The major taxonomic categories from most inclusive biggest set domain to least inclusive smallest set single species 1 member are Did King Philip Come Over For Good Spaghetti Domain Kingdom Phylum Class Order Family Genus Species Genus groups together closely related organisms which may or may not interbreed The separation based on interbreeding defines the category species Species the biological group which includes all the organisms which are or have the potential for interbreeding biological species concept Many species were originally distinguished by morphology if two organisms look alike they must be the same species however biological species are based on the ability to reproduce in nature Individuals may look similar but not reproduce and therefore are not the same species Ex Eastern western and mountain blue birds Also individuals may look different but can reproduce and therefore are the same species Ex dogs lab Great Dane etc Historically taxonomy is an inexact process Organisms which were once placed together in a certain classification group have been separated when new or better evidence is uncovered Ex DNA sequencing or genomes Relatedness can be determined by comparing DNA sequences Chromosomes banding patterns of humans and chimps are over 99 identical With the new technology we can find out better which animals are more closely related DNA wise rather than looks As the DNA for more organisms is studies the placement of organisms within the taxonomic categories gets more solid Biodiversity species and possibly 5 to 75 times more which have not been classified Individuals in species also look different because of adaptations to regions environment etc Ex Home sapiens the more biologists look the more species are found There are about 1 4 million identified Chapter 19 The Hidden World of Microbes things too small to be seen with the naked eye Bioterrorism using living agents to cause terror EX anthrax A virus is not considered a living thing it s neither bacteria archaea nor eukarya It cannot produce on its on it has to infect cells EX smallpox if you get it 30 chance you will die and it s very easily transmissible from person to person Microbe something too small to be seen without a microscope Prokaryotes range in size 0 2 1 0 m almost always microscopic Unicellular eukaryotes range in size 10 100 m algae pond scum etc could be a pro or eukaryote A m or a micrometer is 1 1 000 000 of a meter The period at the end of a sentence is about 1 000 m Biggest difference between prokaryotic eukaryotic cells organization of materials Viruses range in size 0 05 0 2 m and come in many different shapes rabies herpes measles tobacco mosaic plant first discovered virus in a plant chicken pox shingles and bacteriophage infects bacteria EX T7 infects ecoli Other biological entities are not organisms because they don t have all of the characteristics of living organisms Viruses have 3 main parts Genome genetic information Can be either single stranded or double stranded DNA or RNA Capsid a protein coat that surrounds and protects the genome Envelope membrane phospholipid bilayer love hate water that surrounds the capsid Viruses hijack cells they cannot reproduce unless they have a living host They can usually be highly specific for the organism it infects swine flu avian flu etc Chapter 36 Defense Against Disease The Immune System Do not come in contact with these things as much as you can HIV mutates or changes 1 000 times faster than the flu that s why it s so hard to develop a vaccine for it because the strains are always changing Three main lines of defense Keep the germs away Nonspecific external barriers skin mucus membranes etc Skin good at keeping microbes out of our body physical barrier to microbial entry inhospitable environment for growth dry dead cells at surface Sweat sebaceous glands secreting acids natural antibiotics like lactic acid Mucus membranes of respiratory and digestive tracts well defined secretions have antibacterial enzymes Stomach if microbes swallowed acids and protein digesting enzymes destroy them inflammation fever natural killer cells Nonspecific internal defenses Phagocytic white blood cells WBCs in extracellular fluid amoeboid shape destroy microbes by phagocytosis Natural killer cells WBCs that destroy body cells by viruses and cancerous cells by punching HOLES in them it contacts the infected cell and releases pore forming proteins pore forming proteins insert into the plasma membrane of the infected cell self assembling into large pores Inflammatory response caused by a relatively large scale microbial invasion through wound Steroid injections antihistamines reduce the inflammatory response Histamine is released when cell damage is detected like a splinter Histamine increases the blood flow by dilating capillaries and making them slightly bigger to effectively was out the wound leads to the red swollen warm feeling This is a good response you want your body to do this Other chemicals from damaged cells attract Phagocytic WBCs that engulf bacteria dirt and tissue debris first responders macrophages Blood clotting alls off wounded area Pus formed is just WBC dying off o 1 Tissue damage carries bacteria into the wound o 2 Wounded cells release chemicals that stimulate mast cells o 3 Mast cells blood stream release histamine to increase blood flow and to allow WBCs to leave the Produce histamine Store histamine Release histamine in a controlled way o 4 Histamine increases capillary blood flow and permeability o 5 Phagocytes leave capillaries smallest part of your circulatory system and ingest bacteria and dead cells Fever response to microbes establishing major infection Low grade fevers 100 102 degrees are beneficial o Slows down microbial reproduction o
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