CLASSIFICATION Topic 5.5 IB Biology Miss Werba

TOPIC 5 – ECOLOGY and EVOLUTION 5.1 COMMUNITIES and ECOSYSTEMS 5.2 THE GREENHOUSE EFFECT 5.3 POPULATIONS 5.4 EVOLUTION 5.5 CLASSIFICATION J WERBA – IB BIOLOGY 2

THINGS TO COVER Binomial system of nomenclature Hierarchy of taxa Phyla of the Plant Kingdom Phyla of the Animal Kingdom Dichotomous keys J WERBA – IB BIOLOGY 3

BINOMIAL SYSTEM OF NOMENCLATURE 5.5.1 BINOMIAL SYSTEM OF NOMENCLATURE Created by Carl Linnaeus Everything given two latin names: Genus followed by species It is written in italics (typed) or underlined (written) The genus name can be shortened to its first initial The species name is always in lowercase J WERBA – IB BIOLOGY 4

BINOMIAL SYSTEM OF NOMENCLATURE 5.5.1 BINOMIAL SYSTEM OF NOMENCLATURE Examples: Humans: Homo sapiens or H. sapiens Lions: Panthera leo or P. leo Meerkats: Suricatta surricata or S. surricata J WERBA – IB BIOLOGY 5

HIERARCHY OF TAXA Taxa: groups within the classification system 5.5.2 HIERARCHY OF TAXA Taxa: groups within the classification system The hirerachy of taxa refers to the system of classification which organises organisms into groups of increasing specificity J WERBA – IB BIOLOGY 6

HIERARCHY OF TAXA Kingdom King Phylum Prawns Class Come Order On 5.5.2 HIERARCHY OF TAXA ACTUAL PNEUMONIC Kingdom King Phylum Prawns Class Come Order On Family Fresh Genus Green Species Salad J WERBA – IB BIOLOGY 7

HIERARCHY OF TAXA Kingdom Phylum Class Order Family Genus Species 5.5.2 HIERARCHY OF TAXA HIERARCHY ANIMAL EXAMPLE: HUMAN Kingdom Animalia Phylum Chordata Class Mammalia Order Primates Family Hominidae Genus Homo Species Homo sapien J WERBA – IB BIOLOGY 8

HIERARCHY OF TAXA Kingdom Phylum Class Order Family Genus Species 5.5.2 HIERARCHY OF TAXA HIERARCHY PLANT EXAMPLE: MOUNTAIN ASH Kingdom Plantae Phylum Magnoliophyta Class Magnoliopsida Order Myrtales Family Myrtaceae Genus Eucalyptus Species Eucalyptus regnans J WERBA – IB BIOLOGY 9

HIERARCHY OF TAXA Kingdom Phylum Class Order Family Genus Species 5.5.2 HIERARCHY OF TAXA HIERARCHY ANIMAL EXAMPLE: BLUE WHALE Kingdom Animalia Phylum Chordata Class Mammalia Order Cetacea Family Balaenopteridae Genus Balaenoptera Species Balaenoptera musculus or B. musculus J WERBA – IB BIOLOGY 10

HIERARCHY OF TAXA Kingdom Phylum Class Order Family Genus Species 5.5.2 HIERARCHY OF TAXA HIERARCHY PLANT EXAMPLE: DANDELION Kingdom Plantae Phylum Tracheophyta Class Angiospermae Order Asterales Family Asteraceae Genus Taraxacum Species Taraxacum officinale or T.officinale J WERBA – IB BIOLOGY 11

KINGDOM PLANTAE Photosynthetic Chlorophyll Cellulose cell wall 5.5.3 KINGDOM PLANTAE Photosynthetic Chlorophyll Cellulose cell wall Vacuoles permanent Store starch 4 main phyla J WERBA – IB BIOLOGY 12

KINGDOM PLANTAE Angiospermophyta (flowering plants) 5.5.3 KINGDOM PLANTAE Bryophyta (mosses) Filicinophyta (ferns) Coniferophyta (woody trees) Angiospermophyta (flowering plants) J WERBA – IB BIOLOGY 13

True leaves, roots & stems 5.5.3 KINGDOM PLANTAE Phyla True leaves, roots & stems Seeds Flowers Vascular tissue Other features Bryophyta (mosses) no No true roots, only rhizoids Filicinophyta (ferns) yes yes (primitive) Large fronds Rhizomes Produce spores Coniferophyta (woody trees) Narrow leaves Woody stems Seeds in cones Angiospermophyta (flowering plants) Have flowers Seeds in fruits J WERBA – IB BIOLOGY 14

5.5.4 KINGDOM ANIMALIA The syllabus specifies 6 of the 30 or more phyla from the animal kingdom. The ones selected are invertebrates, meaning they do not have a spinal cord. heterotrophic no cell walls no vacuoles no chlorophyll store glycogen J WERBA – IB BIOLOGY 15

KINGDOM ANIMALIA Mollusca (molluscs) Annelida (worms) 5.5.4 KINGDOM ANIMALIA Porifera (sponges) Platyhelminthes (flatworms) Mollusca (molluscs) Cnidaria (jellies, coral, sea anemones) Annelida (worms) Arthopoda (insects, crustaceans, spiders) J WERBA – IB BIOLOGY 16

KINGDOM ANIMALIA Phyla Symmetry Body layers Segmented body 5.5.4 KINGDOM ANIMALIA Phyla Symmetry Body layers Segmented body Other features Porifera (sponges) asymmetric none no Small holes to filter air/food Cnidaria (jellyfish, coral) radial 2 Stinging cells Platyhelminthes (flatworms) bilateral 3 No body cavity Soft/flat Annelida (worms, leeches) yes Ringed segmentation with some specialisation Mollusca (snails, octopi) May have a shell Extremely varied Arthropoda (insects, spiders) Hard exoskeleton (chitin) Jointed appendages J WERBA – IB BIOLOGY 17

DICHOTOMOUS KEYS Method of identification of organisms 5.5.5 DICHOTOMOUS KEYS Method of identification of organisms Groups of organisms are divided into two categories sequentially, until all organisms are individually identified In most cases, the characteristic should be readily observed or measurable. Shape and number are often good characteristics on which to base alternative pairings. J WERBA – IB BIOLOGY 18

DICHOTOMOUS KEYS 2 types: Numbered key Branching key 5.5.5 J WERBA – IB BIOLOGY 19

Sample questions Q1 A collection of four animal specimens is observed and a dichotomous key is applied. Which specimen is an arthropod? Non-segmented body ......................................... go to 2 Segmented body ................................................. go to 3 Body is not symmetrical ..................................... specimen A Body is symmetrical ............................................ specimen B Jointed appendages present .............................. specimen C Jointed appendages absent ............................... specimen D Specimen A Specimen B Specimen C Specimen D J WERBA – IB BIOLOGY 20

Sample questions Q2 Identify which phyla of plants fit each of the brief descriptions below: Evergreen woody plant; leaves are shaped like needles; seed-producing with reproductive structures in cones. Phylum: ______________________ Underground stem that bears roots and leaves called fronds; spores develop in spore cases called sporangia located on the underside of fronds. Phylum: ______________________ J WERBA – IB BIOLOGY 21

Sample questions A1. C A2. i. coniferophyta ii. filicinophyta J WERBA – IB BIOLOGY 22

Sample questions Q3 Using simple external recognition features, distinguish between the plant phyla bryophyta and angiospermophyta. J WERBA – IB BIOLOGY 23

Sample questions A3 J WERBA – IB BIOLOGY 24