1. 5.5 CLASSIFICATION
Ms. TRS

2. ANIMALIA ( multicellular heterotrophs)
FUNGI –eukaryotic, multicellular ( except yeast), saprotrophs
PLANTAE (eukaryotic, multicellular autotrophs)
PROKARYOTA ( bacteria – unicelluar prokaryotic ,auto- or heterotrophic forms)
PROTOCTISTA – unicellular eukaryotic heterotrophs with a few exceptions

3. 5.5.1: Binomial system of nomenclature
Designed by Carolus Linneaus in 18th century
Every species has a Latin name, made up of two parts
First part is the name of the Genus
Second part specifies the species
Name should be printed in italics (underlined if hand written) and first part capitalized
Example
Humans are Homo sapiens

4. Homo sapiens BINOMIAL SYSTEM OF NOMENCLATURE: Two named Naming system
Developed by Carl Linnaeus – a Swedish Bottanist
(1707 – 1778)
Homo sapiens
First name = capital letter; if typed always in italics; if handwritten always underlined
Exam question:
Outline the binomial system of nomenclature
(4)
GENUS SPECIES

5. Discuss the value of classifying organisms [2]
Answer:
Called binomial because two names are used;
First name is genus, with first name being a capital;
Second name is species, with no capital;
Italics are used when the name is printed;
The name is underlined if it is handwritten;
Discuss the value of classifying organisms [2]
Species Classification - It is easier to find out which species an organism belongs to when you have other organisms to compare it to;
You can make assumptions about characteristics of a species in general;
Evolutionary links, you can make assumptions about traits of a common ancestor; You can also predict how they evolved.

6. Which of these two reef sharks are most closely related and why?
Carcharhinus
Perezi
Carcharhinus melanopterus
Triaenodon
Obesus
Same genus, different species

7. 5.5.2: Hierarchical system of classification
The Hierarchical system has seven levels called taxons (plural: taxa)
Each taxon can contain one or more of the sub-group below it
The seven level hierarchies of taxa are:
Kingdom
Phylum
3. Class
4. Order
5. Family
6. Genus
7. Species
To remember the taxa in the correct order:
King Philip Came Over For Good Spagetti

9. Kingdom Animalia Plantae Phylum Chordata Angiospermae Class Mammalia
Dicotyledoneae
Order
Primate
Rosales
Family
Hominidae
Papilionaceae
Genus
Homo
Pisum
species
sapiens
sativum

10. 5.5.3: Distinguish between Plant Phyla
Kingdom: Plantae
Characteristics:
Photosynthetic
Chlorophyll
Cellulose cell wall
Permanent vacuoles
Stores starch
Classification of the major plant phyla is based on external observable structures
Main points: 1.roots, leaves and stems;
2. vascular tissue;
3. reproduction

11. 4 Major plant phyla
Bryophyta – Filicinophyta Coniferophyta Angiospermophyta -

12. PLANTAE Bryophyta Filicinophyta (mosses) (ferns) Coniferophyta
(conifers)
Bryophyta
(mosses)
Filicinophyta
(ferns)
Angiospermophyta
(flowering plants)
No roots or stem
Small leaf like structures, rhizoids for roots
No vascular tissue
Reproduce using spores
Spores are formed in capsules
Roots, leaves and short stems
Leaves divided into sections and curled
Have vascular tissue
Reproduce using spores produced under leaves
Woody trees
Have narrow needles for leaves with thick waxy cuticle
Have vascular tissue
Reproduce using seeds in cones, not enclosed in fruits
Wind pollinated
Roots, leaves and stems, stem can be woody
Have vascular tissue
Produce flowers
Seeds are enclosed in ovaries that form fruits
Seeds dispersed through fruits

13. Division Bryophyta No true roots, stem or leaves
Have rhizoids instead of roots
No vascular tissue – must absorb water from surface instead of absorbing from roots
Reproduce by spores made in capsules
Moss are commonly found in damp, shady areas

14. Filicinophyta (ferns)
Have true roots, stem and leaves. Stem not woody in most of the plants
First group of vascular plants:
Xylem and phloem transport resources between distant organs.
Reproduce by spores made in sporangia under leave
Seen in tropical and temperate forests

15. Coniferophyta
Includes ~ 550 species of large trees with thick woody stem including pines, firs, spruces, and redwoods
Most conifers have needles or narrow leaves modified to prevent water loss and thick waxy cuticle
Have vascular tissue
All produce seeds in cones
Seeds are not enclosed in ovary or fruit.
Most use wind pollination for reproduction.
Almost all conifers are evergreens

16. Angiospemophyta True flowering plants
Angion means “container,” – seeds are enclosed in fruits. During development, the ovule becomes seed and the ovary becomes fruit.
Includes ~ 235,000 species of flowering plants
May rely on wind, birds, insects, and even mammals for pollination and reproduction.
Have vascular tissue

18. IB exam questions
Plants are a diverse group of eukaryotic organisms. Describe the different characteristics of the bryophyta, filicinophyta, coniferophyta and angiospermophyta marks
Outline the structural differences that characterize bryophytes, filicinophytes, coniferophytes and angiospermophytes marks

19. Bryophyta:
No roots, have rhizoids, simple stem and leaves
Non vascular
Produce spores in capsule
Filicinophyta:
Have roots, stems and leaves, leaves are large and divided into sections
Have primitive vascular tissue
Reproduce by making spores in sporangia on the underside of leaves
Coniferophyta:
Have woody stem, narrow needle like leaves with thick waxy cuticle
Have well developed vascular tissue
Produce seeds in cones
Seeds are not enclosed in fruits
Angiospermophyta:
Produce flowers
Flowers have ovules in ovaries
Seeds are enclosed in fruits.( ovules form seeds and ovary forms fruit)

20. 5.5.4 Distinguish between the major invertebrate phyla using external features

21. Features of invertebrate phyla
Phylum
Symmetry
Digestive tract
Segmentation
Other features
Porifera
Example:
Cnidaria
Platyhelminthes
Example
Annelida
Mollusca
Arthropoda

22. ANIMALIA Invertebrates Porifera (sponges) Cnidaria
No symmetry
No mouth or anus
No segmentation
Water flows in and out of body through pores
Porifera
(sponges)
Radial symmetry
Tentacles/ One opening to gut
No segmentation
Stinging cells - nematocysts
ANIMALIA
Cnidaria
(jellyfish/coral polyps)
Bilateral symmetry
One opening to gut
No segmentation
Gas exchange over large surface area
Platyhelminths
(flatworms)
Invertebrates
Annelida
(segmented worms)
Bilateral symmetry
D.T:With Mouth and anus
Very segmented
Bristles on body/
Mollusca
(snails/clams/
octopuses)
Usually bilateral/ no segmentation
DT: with Mouth and anus
Most of them have a calcium shell covering soft body
Arthropoda
(insects/spiders/crustaceans, millipedes)
Bilateral symmetry
D.T : with Mouth and anus
segmented
Jointed legs + exoskeleton of chitin

23. Phylum Porifera Includes sponges
Characteristics: no body symmetry, no tissues, no organs; hermaphrodites; filter feeders; water moves in and out of the body through pores; sessile

24. Phylum Cnidaria Includes corals, jellyfish, and sea anemone
Characteristics: stinging cells for food and protection; one-way digestive tract; radial symmetry; no segmentation drifters or sessile

25. Phylum Platyhelminthes
Includes flatworms like planaria, flukes, and tapeworms.
Characteristics: distinct head region (cephalization); bilateral symmetry; most are parasites; one-way digestive tract; no heart or lungs; flat shape - why?
5.5.4

26. Phylum Annelida Includes earthworms, marine worms, and leeches.
Characteristics: segmented; bilaterally symmetrical; well developed nervous, digestive, and circulatory systems; two-way digestive system.
5.5.4

27. Phylum Mollusca Includes snails, clams, octopus and squids.
Characteristics: bilateral symmetry; two-way digestive tract; exoskeleton (shells) of calcium carbonate; soft bodies; most are aquatic
5.5.4

28. Phylum Arthropoda
Includes insects, arachnids (spiders), and crustaceans
Characteristics of all arthropods: exoskeleton made of chitin; jointed appendages; segmented body; bilateral symmetry, open circulatory system
Molting – process of shedding and exoskeleton and growing a new one to grow larger.

30. Dichotomous Key
A dichotomous key is a method used to identify organisms according to their physical traits based on a system of answering yes or no questions about an organism. Through a process of elimination the organism is identified.
Visible features are used
Questions should be unambiguous
Each question should divide the organisms into two distinct groups
Identification game:

32. IB exam questions Which phylum does sponges belong to?
What is the important feature of flat worms?