2 Biology – The study of lifeOrganism – Anything capable of carrying on life processesBranches of biology –There are many subtopics within biology – a few examples we’ll hit upon this year:
3 Biochemistry – Chemical substances and processes in organisms Genetics – Inheritance – passing of traits from one generation to nextEvolution – Change in organisms over timeCell biology – Cell structure and functionZoology – AnimalsAnatomy – Structures of organismsPhysiology – Functions, activities, and processes of organismsEcology – Interactions of organisms and environment
4 Characteristics of Life Made of cellsCan be unicellular or multicellularMulticellular organisms - more than 1 cellCells in these organisms are considered specialized (have certain jobs)Examples: some fungus, plants, and animals
5 Unicellular organisms - one cell1 cell does all jobs for organismExamples: bacteria, protists, and some fungus
6 2. Organization – levels of organization vary based on how complex the organism isIn general: cells tissues organs organ systems organismsCells are the smallest unit of life, organisms the biggest
8 3. Living things use energyHeterotrophs are organisms that obtain nutrients from food eatenEx: some bacteria and protists, fungus, & animalsAutotrophs are organisms that make their own food through photosynthesisEx: plants, some protists, and some bacteria
9 4. HomeostasisMaintaining (relatively) constant internal conditions (such as body temperature, pH, blood pressure, water balance) regardless of external changesExamples: sweating or shivering to maintain body temperature
10 5. Living things grow and developGrowth – an increase in the number of cells/ increase in the sizeExample – getting tallerDevelopment – Changes an organism undergoes to reach adult formExample – baby kid teen adult
11 6. Living things reproduceReproduction – production of offspringPrevents extinction of speciesCan be sexual or asexual
12 Asexual reproduction – only 1 parent; offspring has DNA identical to parentSexual reproduction – 2 parents, each parent contributes ½ genetic information to offspring; offspring has mixed traits from parents
13 ClassificationTaxonomy – The science of identifying, classifying, and naming organismsTaxa –the categories into which organisms are classified
14 The taxa:KingdomPhylum (Division for plants)ClassOrderFamilyGenus SpeciesKing Phillip Came Over For Good Spaghetti
17 Why can’t we just use common names? Not very specificEx: What KIND of frog?MisleadingEx: Jellyfish is NOT a fish, ringworm is NOT a wormVary by language and geographyEx: Puma, mountain lion, and cougar are ALL the same animal!
18 What was wrong with the early systems of classification? Forgot to include bacteria, fungus and protistsFailed to show proper relationships between organismsToo general – ex. Aristotle classified animals by where they lived (air, land, or water)
19 Modern system of classification: Based in part on Carolus Linnaeus’ system of binomial nomenclature (“two names”)Grouped according to physical features and their evolutionary history (phylogeny)Those placed in the same genus will be most closely related, those in different kingdoms most distantly relatedEx: Those in genus Felis are more closely related to each other than organisms in the Kingdoms Plantae and Animalia are to each other.
20 Writing scientific names:Ex: Homo sapiens or Homo sapiensCan be abbreviated H. sapiensIf typed – should be italicized.If handwritten – should be underlined.First word is genus – capitalizedSecond word is species - lower case