BIOLOGY The Study of Life bios life ology study of What is LIFE I know it when I see it What are some characteristics we associate with the definition life What are the Properties of Life 1 Precise organization order 2 Homeostasis 3 Response to the environment 4 Energy uptake and use 5 Growth and development 6 Reproduction 7 Ability to Evolve Properties of Life 1 Order Properties of Life 2 Homeostasis Properties of Life 3 Response to the Environment Properties of Life 4 Energy Processing Properties of Life 5 Growth and Development Properties of Life 6 Reproduction Properties of Life 7 Evolution Adaptation Properties of Life 1 Precise organization order 2 Homeostasis 3 Response to the environment 4 Energy uptake and use 5 Growth and development 6 Reproduction 7 Ability to Evolve Is It Alive Why or Why Not Cologne Cathedral Baby Chicken Escherichia coli bacteria Hoover Dam Levels of Organization Biosphere Populations Ecosystems Individuals Communities Organs or Organ Systems Levels of Organization Organs or Organ Systems Organelles Tissues Molecules Cells Emergent Properties Each level of the biological hierarchy is more than merely the sum of its parts Emergent properties result from interactions among components at each level Emergent Properties Properties Life itself is an emergent property Cells are the simplest units of life life The cell is the lowest level of structure that has all of the properties or qualities we use to define life Some organisms consist of a single cell others are multicellular aggregates of specialized cells The first cells were observed and named by Robert Hooke in 1665 from a slice of cork Hooke s Compound Microscope Observation XVIII of the Micrographia Anton van Leeuwenhoek was the first to see single celled organisms in pond water and observe cells in blood and sperm Anton van Leewenhoek No more pleasant site has met my eye than this Van Leewenhoek s simple microscope Leeuwenhoek reported how in the plaque scraped from his teeth I then most always saw with great wonder that in the said matter there were many very little living animalcules very prettily a moving The biggest sort had a very strong and swift motion and shot through the spittle like a pike does through the water In the mouth an old man who had reportedly never cleaned his teeth in his life an unbelievably great company of living animalcules a swimming more nimbly than any I had ever seen up to this time THE CELL THEORY In 1839 Matthais Schleiden and Theodor Schwann extrapolated from their own microscopic research and that of others to propose the cell theory The cell theory postulates that cells are the basic unit of structure and physiology in all living things One of the great paradigms of Biology Cell Theory is to Biology as the Atomic Theory is to Physics But Thought cells formed spontaneously in a manner similar to crystal growth In 1855 Rudolf Virchow extended the cell theory New cells are produced by the division of existing cells Critical process in reproduction growth and repair of multicellular organisms All cells are enclosed by a membrane that regulates the passage of materials between the cell and its surroundings All cells contain DNA the heritable material that directs the cell s activities Two major kinds of cells prokaryotic cells and eukaryotic cells can be distinguished by their structural organization The cells of the microorganisms called bacteria and archaea are prokaryotic Do not contain organelles All other forms of life have the more complex eukaryotic cells The continuity of life is based on heritable information in the form of DNA Biological instructions for life are encoded in DNA deoxyribonucleic acid DNA is the substance of genes Genomes Human and Others The entire library of genetic instructions that an organism inherits is called its genome The genome of a human cell is 3 billion chemical letters long The rough draft of the sequence of nucleotides in the human genome was published in 2001 Biologists are learning the functions of thousands of genes and how their activities are coordinated in the development of an organism Unity Diversity Diversity 1 5 million species described third million plant species 50 000 vertebrates almost 1 million insects Estimates 5 30 million species 10 described Diversity decreasing as species go extinct Unity Diversity Taxonomy classifying and organizing life 7 Unity Diversity Taxonomy classifying and organizing life species Spaghetti Genus Good Family For Order Over Class Came Phylum Phillip Kingdom King Examples from the Animal Kingdom ORGANISM GROUP NAME HUMAN CHIMPANZEE HOUSE CAT KINGDOM Animalia Animalia Animalia PHYLUM Chordate Chordate Chordate CLASS Mammal Mammal Mammal ORDER Primates Primates Carnivora FAMILY Hominidae Pongidae Felidae GENUS Homo Pan Felis SPECIES sapiens Homo sapiens troglodytes domestica Animali a Chordat e Mammal Carnivor a Felidae Panther a leo Pan troglodytes Felis domestica Felis leo Scientific Name LION HOUSEFLY Animalia Arthropoda Insect Diptera Muscidae Musca domestica Musca domestica Unity Diversity DOMAINS 1 Bacteria 2 Archea 3 Eukarya 1 Plantae 2 Animalia 3 Fungi 4 Protista Monera Unity Diversity 5 Kingdoms 1 2 3 4 5 Monera Bacteria Plantae Plants Animalia Animals Fungi Fungi Protista Protists Unity Diversity Unity within diversity DNA as the common information molecule Eukaryotes all share common cellular architecture The Nature of Science the scientific method Science is a process of inquiry that includes repeatable observations and testable hypotheses A Discovery Science Induction B Hypotheticodeductive model Observations Scientific method Data collection Formal process In field or lab Experimentation In field or lab How weird some of the frogs in this pond have 3 back legs What the heck is going on here Puzzling observation Causal question Causal Questions Ask what is CAUSING a particular phenomenon or observation What causes frog deformities CAUSATION is very different from CORRELATION Causal question What is causing these frog deformities Possible explanations hypotheses Polluted water e g herbicide runoff from fields Infection by parasites Increased UV radiation CAUSATION does not equal CORRELATION Not all explanations are hypotheses Elves cast a spell on the frogs God made them that way A possible explanation about what CAUSES something is a HYPOTHESIS Pollution is causes leg deformities in leopard frogs Prediction IF frog deformities are caused by polluted water THEN there