Post on 31-Mar-2015
Great Ideas in Science Great Ideas in Science Lecture 10 - Living ThingsLecture 10 - Living Things
Prof. Robert HazenProf. Robert HazenUNIV-301UNIV-301
Every Living thing…Every Living thing…1.1. Can be Can be classifiedclassified in one scheme in one scheme2.2. Is Is modularmodular – composed of a few – composed of a few
simple moleculessimple molecules3.3. Is made of Is made of cellscells – life – life’’s chemical s chemical
factoriesfactories4.4. Uses the same Uses the same genetic codegenetic code5.5. EvolvedEvolved from a first cell by from a first cell by natural natural
selectionselection6.6. Lives in Lives in ecosystemsecosystems of many of many
interdependent organismsinterdependent organisms
Ways of Thinking Ways of Thinking About Living ThingsAbout Living Things
Biosphere Biosphere Ecosystem Ecosystem CommunityCommunity PopulationPopulation OrganismOrganism Anatomy & Anatomy &
physiologyphysiology CellularCellular MolecularMolecular
What is Life?What is Life?
EncapsulationEncapsulation: All life is separated : All life is separated from the environment by a from the environment by a membranemembrane..
MetabolismMetabolism: All life obtains : All life obtains energyenergy and and atomsatoms from the environment. from the environment.
ReproductionReproduction: All life reproduces : All life reproduces via via geneticsgenetics..
The Characteristics of The Characteristics of LifeLife High degree of order and complexityHigh degree of order and complexity
Part of larger systems of matter and energyPart of larger systems of matter and energy
Life depends on chemical reactions in cellsLife depends on chemical reactions in cells
Life requires liquid waterLife requires liquid water
Organisms grow and developOrganisms grow and develop
Regulate energy useRegulate energy use
Share same genetic code, code is heritableShare same genetic code, code is heritable
All living things are descended from a All living things are descended from a common ancestorcommon ancestor
Linnaean classificationLinnaean classification
HierarchyHierarchy KingdomKingdom PhylumPhylum ClassClass OrderOrder FamilyFamily GenusGenus Species Species
Great Idea: Living things use many different strategies to deal with the
problems of acquiring and using matter and energy.
Why is Taxonomy Why is Taxonomy Important?Important?
Think about how to describe a tree.Think about how to describe a tree.
Names are essential for accurate Names are essential for accurate communicationscommunications
But taxonomy can be ratherBut taxonomy can be rather arbitraryarbitrary
Lumpers versus splittersLumpers versus splitters
Local variations in speciesLocal variations in species
Why is Taxonomy Why is Taxonomy Important?Important?
Dracorex (top left) and Stygimoloch (top right), as growth stages of Pachycephalosaurus (bottom).
Why is Taxonomy Why is Taxonomy Important?Important?
A B C
Classifying LifeClassifying Life KingdomsKingdoms
MoneraMonera ProtistaProtista FungiFungi PlantsPlants Animals Animals
Taxonomy of AnimalsTaxonomy of Animals
Classifying Human BeingsClassifying Human Beings
Kingdom: AnimalsKingdom: Animals Phylum: ChordatesPhylum: Chordates
Subphylum: vertebratesSubphylum: vertebrates Class: MammalsClass: Mammals Order: PrimatesOrder: Primates Family: Family: HominidHominid Genus: Genus: HomoHomo Species: Species: sapienssapiens
A New View:A New View:Three Domains of LifeThree Domains of Life
BacteriaBacteria
ArchaeaArchaea
EukaryaEukarya
Implications of Implications of Linnaean Classification Linnaean Classification
You can use genetic material.You can use genetic material. Similarities depend on time and change.Similarities depend on time and change. Classification results from real events.Classification results from real events.
“Nothing in biology makes sense except in the light of evolution.”
Strategies of FungiStrategies of Fungi
GrowthGrowth FilamentsFilaments Decomposers Decomposers
StructureStructure Mass of filamentsMass of filaments Many formsMany forms
ReproductionReproduction Break filamentsBreak filaments Spores (usually asexual)Spores (usually asexual)
LichensLichens Fungi + AlgaeFungi + Algae Two interdependent speciesTwo interdependent species
The Simplest PlantsThe Simplest Plants Phylum: BryophytesPhylum: Bryophytes StructureStructure
No rootsNo roots Photosynthetic Photosynthetic
ReproductionReproduction Sexual Sexual AsexualAsexual
Vascular PlantsVascular Plants Phylum: vascular plantsPhylum: vascular plants StructureStructure
Roots, stems, leavesRoots, stems, leaves Control water lossControl water loss
ReproductionReproduction Spore = fertilized eggSpore = fertilized egg Cone = holds egg or spermCone = holds egg or sperm Seed = egg plus nutrientsSeed = egg plus nutrients Pollen = spermPollen = sperm
StrategiesStrategies Seedless (Ferns - spores)Seedless (Ferns - spores) Seeds but no flowers Seeds but no flowers
(Gymnosperms - cones)(Gymnosperms - cones) Seeds and flowers Seeds and flowers
(Angiosperms)(Angiosperms)
AngiospermsAngiosperms
InvertebratesInvertebrates No backboneNo backbone Most diverse animalsMost diverse animals
ArthropodsArthropods 70% of known animal 70% of known animal
speciesspecies
StructureStructure ExoskeletonExoskeleton Jointed legsJointed legs
The Molecules of LifeThe Molecules of Life
All life is All life is modularmodular – composed – composed of a few simple molecules.of a few simple molecules.
Key Ideas about the Key Ideas about the molecules of lifemolecules of life
Based on Carbon (Organic chemistry)Based on Carbon (Organic chemistry)
Six main elements (CHNOPS)Six main elements (CHNOPS)
Modular; built from simple unitsModular; built from simple units
Molecular shapes determine their Molecular shapes determine their functionfunction
Nutrition FactsNutrition Facts
LipidsLipids SugarsSugars Amino acidsAmino acids
EnergyEnergy
Carbohydrates (sugars)Carbohydrates (sugars)
Carbon
Hydrogen
Oxygen
Cellulose and StarchCellulose and Starch
LipidsLipids
Saturated and Saturated and Unsaturated LipidsUnsaturated Lipids
Amino AcidsAmino Acids
Amino groupAmino group Carboxyl groupCarboxyl group Side-group (20 Side-group (20
different things)different things)
Protein – sequence of Protein – sequence of amino acidsamino acids
Primary – chain of Primary – chain of amino acidsamino acids
Secondary – folding of Secondary – folding of chainchain
TertiaryTertiary QuaternaryQuaternary
ProteinsProteins Structural roleStructural role
Proteins – EnzymesProteins – Enzymes
Dietary Amino AcidsDietary Amino Acids