Entire Taxonomy presentation (all domains, kingdoms, etc)

2. Biology
S.Rucker

3.  Scientists classify organisms and assign each
organism a universally accepted name

4.  To organize similar organisms
 So all scientists are discussing the same
organisms (species)
 Species  population of organisms that share similar
characteristics and can breed with one another and
produce fertile offspring
 Identified 1.5 million species so far
 Estimate 2-100 million have yet to be discovered

5. What tools can we use to show similarities
in organisms?
 Cladistic analysis  identifies and considers
only those characteristics of organisms that are
evolutionary innovations – new characteristics
that arise as lineages evolve over time
 Cladogram – diagram that shows evolutionary
relationships among a group of organisms

6. Modern Evolutionary Classification
Darwin’s ideas about descent gave
rise to the study of phylogeny –
evolutionary relationships among
organisms
Evolutionary Classification – Grouping
of organisms based on evolutionary
history

7. Appendages Conical Shells Crustaceans Gastropod
Crab Barnacle Limpet Crab Barnacle Limpet
Molted
exoskeleton
Segmentation
Tiny free-swimming larva
CLASSIFICATION
BASED ON VISIBLE CLADOGRAM
SIMILARITIES

8.  Genes of many organisms show important
similarities at a molecular level. Similarities in
DNA can be used to help determine
classification and evolutionary relationships

9.  Swedish botanist that developed a two-word
naming system called BINOMIAL
NOMENCLATURE
 Gives the Genus and species name, written in italics or
underlined
 Language is usually Latin
 Example:
 House cat – Felis domesticus
 Dog – Canis familaris
 Human – Homo sapien

10.  Domain (most inclusive, less in common)
 Kingdom
 Phylum
 Class
 Order
 Family
 Genus
 Species (less inclusive, more in common)
 Each level is called a TAXON; taxa (plural)

11. Black bear Giant Abert Coral
Grizzly bear Red fox
panda squirrel snake Sea star
KINGDOM Animalia
PHYLUM Chordata
CLASS Mammalia
ORDER Carnivora
FAMILY Ursidae
GENUS Ursus
SPECIES Ursus arctos

12.  Currently, all organisms are grouped into 1 of
3 domains which reflect evolutionary
relationships
 1) Bacteria
 2) Archaea
 3) Eukarya EUKARYA
ARCHAEA
Kingdoms
BACTERIA Eubacteria
Archaebacteria
Protista
Plantae
Fungi
Animalia
LUCA – last universal common ancestor

13.  Contains only one kingdom – Eubacteria
Cell type: Prokaryote
Cell structures: Cells with peptidoglycan
# of cells: Unicellular
Nutrition: Autotroph or heterotroph
Examples: Streptococcus, Escherichia coli
These are your ORDINARY, every-day bacteria.

15. E. coli This bacterium (brown) is being attacked by dozens of
bacteriophages (viruses that attack bacteria)

16.  Contains only one kingdom – Archaebacteria
Cell type: Prokaryote
Cell structure: Cell walls without peptidoglycan
# of cells: Unicellular
Nutrition: Autotroph or heterotroph
Examples: Methanogens, halophiles, thermophiles
These are your EXTREME ENVIRONMENT
organisms. Although they are unicellular, they are
probably more closely related to humans than they
are to Eubacteria.

17.  Contains 4 kingdoms
 1) Protista
 2) Fungi
 3) Plantae
 4) Animalia

18.  Cell type: Eukaryote
 Cell structures: Cell walls of cellulose in some
(but not all), some have chloroplasts
 # of cells: Most unicellular; some colonial;
some multicellular
 Nutrition: Autotroph or heterotroph
 Examples: Amoeba, Paramecium, slime molds,
giant kelp, algae

21. Bundles of cilia
Two protozoans… This one is about to be eaten!

22.  Cell type: Eukaryote
 Cell structures: Cell walls of chitin
 # of cells: Most multicellular; some unicellular
 Nutrition: Heterotroph
 Examples: Mushrooms, yeast, mold

24. Extreme close-up of the underside of a mushroom, showing the reproductive
spores (brown dots).

25. ExtrEEEEEEEEme closeup of mushroom spores!

26.  Cell type: Eukaryote
 Cell structures: Cell walls of cellulose; chloroplasts
 # of cells: Multicellular
 Nutrition: Autotroph
 Examples: Mosses, ferns, flowering plants

28.  Cell type: Eukaryote
 Cell structures: No cell walls or chloroplasts
 # of cells: Multicellular
 Nutrition: Heterotroph
 Examples: Sponges, jellyfish, sea anemones, worms,
insects, fishes, mammals, birds, reptiles, amphibians

29.  Kingdom Animalia
 Phylum Chordate
 Class Mammal
 Order Primates
 Family Hominidae
 Genus Homo
 Species Sapiens

30.  Kingdom Animalia
 Phylum Chordate
 Class Mammalia
 Order Carnivora
 Family Felidae
 Genus Felis
 Species Domestica

34. Living
Things
are characterized by Eukaryotic
Prokaryotic cells cells
Important
and differing which place them in
characteristics
Cell wall Domain
such as Eukarya
structures
which place them in which is subdivided into
Kingdom Kingdom
Domain Domain
Plantae Protista
Bacteria Archaea
which coincides with which coincides with Kingdom Kingdom
Fungi Animalia
Kingdom Kingdom
Eubacteria Archaebacteria

36.  Unicellular prokaryotes (no nucleus)
 May be autotrophic or heterotrophic
 Equally small, and appear the same
 Lack membrane-bound organelles such as
mitochondria, ER, Golgi, Lysosomes,etc.
 Have cell walls, cell membrane & ribosomes
 DNA is in the cytoplasm in a circular shape
(called nucleoid)

37. EUBACTERIA ARCHAEBACTERIA
 More diverse  Cell wall lacks
 Live almost everywhere peptidoglycan
(other organisms, soil,  Different membrane
fresh & salt water) lipids
 DNA more similar to
 Cell wall contains the eukaryotes than to
carbohydrate eubacteria, suggesting
peptidoglycan eukaryotes descended
from archaebacteria
 Live in harsh conditions

38. Ribosome
Cell Cell
Peptidoglycan wall membrane
Flagellum DNA Pili

39.  Prokaryotes are identified based on:
 1) Shape
 2) Cell wall composition
 3) Method of movement

40.  Rod shaped (bacilli)
 Spherical (cocci)
 Spirilla (spiral & corkscrew-shaped)

41. GRAM-POSITIVE GRAM-NEGATIVE
 After “Gram staining”  After “Gram staining”
they appear purpleish they appear pinkish
 Has thick layer of  Has thin layer of
peptidoglycan peptidoglycan
 Eg) B. anthracis  Eg) E. coli
(Anthrax!)  Less often pathogenic
 Usually associated with
most pathogenic
bacteria

42. Gram-positive cocci
Gram-negative bacillus

43.  Some don‟t move on their own
 Others move by:
 1) flagella
 2) lash, snake or spiral forward
 3) glide slowly along a layer of slime-like material
they secrete

44.  Obligate aerobes – must have oxygen to survive
 (Obligate means that the organisms are obliged, or required, by their
life processes to live only in that particular way)
 Eg) Mycobacterium tuberculosis which causes TB
 Obligate anaerobes – killed by oxygen
 Eg) Clostridium botulinum can grow in canned food that hasn‟t
been sterilized properly
 Facultative anaerobes – survive with or without
oxygen
 Metabolic pathways can alternate between using oxygen or not
using it.
 Eg) E. coli is a facultative anaerobe that lives anaerobically in the
large intestine and aerobically in sewage or contaminated water.

45.  Asexual using binary fission
 DNA is replicated, cell splits in two. Similar to
mitosis.
 Can happen as quickly as 20 minutes.

46.  Mutations – mistakes during DNA replication
 Conjugation – the exchange of plasmid DNA
between two bacteria
 Can form a pili (tube-like structure) that serves as a transfer
tunnel for the plasmid
 Transformation - engulf “naked” DNA from the
environment and incorporate it into their genome
 Scientists “transform” bacteria to produce insulin

47. Pili

48.  Can form endospores
 A thick-walled internal structure that protects the
DNA and some cytoplasm during periods of
environmental stress (drought, temp, lack of
nutrients)
 Lay “dormant” (inactive) as an endospore until
environmental conditions improve

49. Disease Pathogen Prevention
Tooth decay Streptococcus mutans Regular dental hygiene
Lyme disease Borrelia burgdorferi Protection from tick bites
Tetanus Clostridium tetani Current tetanus vaccination
Tuberculosis Mycobacterium tuberculosis Vaccination
Salmonella food poisoning Salmonella enteritidis Proper food-handling practices
Pneumonia Streptococcus pneumoniae Maintaining good health
Cholera Vibrio cholerae Clean water supplies

50.  Antibiotics – chemicals used to treat bacterial
infection (kill bacteria)
 Antibiotic resistance – when populations of
bacteria are no longer killed by a particular
antibiotic
 Results from OVERUSE of antibiotics
 Happens quickly because bacteria reproduce so
quickly, and “resistant” strains develop rapidly
 This is evolution in action!

51.  some species live in the roots of plants and help
plants absorb nitrogen from the soil
 some decay organic material allowing it to be
recycled
 Used in sewage treatment
 used to make cheeses, sauerkraut, pickles
 used in pharmaceutical industry to make drugs
 Some cause disease such as tuberculosis,
syphilis, scarlet fever, food poisoning, Lyme
disease

52. The good…
…the bad…
…and the ugly.

53.  Multicellular except for yeast
 Eukaryotic heterotrophs
 Extracellular digestion - Fungi secrete enzymes
into the environment, break down organic matter,
then absorb the small nutrient particles
 Major decomposers
 Most are saprobes – digest nonliving organic
matter
 Some are parasites, feeding off other living
organisms

54. Star stinkhorn fungi

55.  Body consists of cells joined to create filaments
 Each microscopic filament of a fungus is called
a hypha
 Hyphae may form a huge tangled interwoven
network called mycelium which can become
visible
 bread mold
 Cell walls are made of a polysaccharide called
chitin

56. Nuclei
Cell wall
Cytoplasm
Cross wall
Nuclei
Cytoplasm Cell wall
Hyphae With Cross Walls Hyphae Without Cross Walls

57. Fruiting body
Hyphae
Mycelium

58.  Most often is asexual
 Filaments break from the main mycelium and grow
into new, identical individuals
 Fungus may produce spores
 Spores disperse, germinate, divide, and produce genetically
identical fungi
 Spores can withstand extreme dryness and cold
 Sexual reproduction occurs
 No males or females, only (+) and (-) types
 Can happen when wandering hyphae meet

59.  Lichens are associations between fungi and
cyanobacteria or algae
 Cyanobacteria or algae are the photosynthetic elements
 Example of mutualism – a symbiotic relationship
where both parties benefit
 The bacteria or algae provide nutrients for themselves and the
fungus
 The fungus provides water and minerals for their metabolism
 Lichens exists in harsh habitats
 Can be found on mountaintops, rock faces in the
desert, and tree bark
 Often first to enter barren environments, breaking down rocks
– help in early stages of soil formation

60. General structure of lichens
Densely packed
hyphae
Layer of
algae/
cyanobacteria
Loosely packed
hyphae
Densely packed
hyphae

62.  Heterotrophic Eukaryotes
 Mostly multicelluar
 Cell walls made of CHITIN
 Mostly DECOMPOSERS and SAPROBES
 Use EXTRACELLULAR DIGESTION
 Mold, mildew, yeast, mushroom, shelf fungi,
ringworm

63. Fungus Among Us

64.  Includes everything except plants, animals, fungi &
bacteria.
 In other words, they are the “everything else” kingdom.
 Very diverse group (over 200,000 species)
 All are eukaryotes (have a nucleus).
 Most unicellular, but some multicellular
 Believed to be the first eukaryotic organisms on Earth.
 “Protista” is Greek for “the very first”
 Biologists don‟t all agree on how to classify protists.
 Usually based on how they obtain nutrition – this is the system
you will learn.

65.  Animal-like Protists – aka. “Protozoans”
 Zooflagellates, Sarcodines, Ciliates, Sporozoans
 Plant-like Protists – aka. “Algae”
 Unicellular Algae
 Euglenophytes, Chrysophytes, Diatoms, Dinoflagellates
 Multicellular Algae
 Red, Brown and Green Algae
 Fungus-like Protists
 Slime molds, water mold

66.  Commonly called protozoans
 All are heterotrophic
 Grouped into four major phyla
 Distinguished by their method of movement
 All are unicellular

67.  Phylum: Zoomastigina
 Characteristics:
 Swim using 1, 2, or many flagella
 Absorb food through cell membrane
 Live in lakes, streams, and inside larger organisms
 Reproduction: usually asexual, but sometimes
sexual
 Example:
 Trichomonas vaginalis – species that causes Trichomonias, an
STD affecting ~180 million people worldwide each year.
 Trypanosoma – causes African sleeping sickness
 Giardia – one more reason you don‟t drink stream water
w/out boil

68.  Phylum: Sarcodina
 Characteristics:
 Move and feed with pseudopods (“false feet”)
 The cytoplasm of the cell streams into the pseudopod, and
the rest of the cell follows. This is called amoeboid
movement.
 Food is surrounded by a pseudopod and taken into the
cell.
 Some form tough outer shells and extend their
pseudopods through openings in the shell.
 Reproduction: asexual
 Example:
 Amoebas
 Entamoeba causes amebic dysentery.
Pseudopods

69.  Phylum: Ciliophora
 Characteristics:
 Use cilia for feeding and movement
 Found in fresh & salt water
 Complex internal structure
 Important feature: Contractile vacuole
 Specialized to collect excess water and pump it out –
maintains stable internal environment (homeostasis)
 Reproduction: usually asexual
 Example:
 Parameciumb

70.  Phylum: Sporozoa
 Characteristics:
 Do not move on their own
 Parasitic – affect worms, fish, birds & humans
 Reproduction: sexual and asexual
 Example:
 Plasmodium causes malaria. Plasmodium reproduces
sexually inside the female Anopheles mosquito without
harming the mosquito. Mosquito bites transfer
sporozoites into human blood – sporozoites reproduce
asexually inside humans and destroy liver and blood
cells.

71.  Play essential roles in the living world
 Recycle nutrients
 Many organisms depend on them for food
 Cause enormous amounts of disease
 Fun example: Termites
 Termites eat wood, but do not have the necessary
enzymes to break down the cellulose in wood. The
zooflagellate Trichonympha lives inside the termites
gut and produces cellulase, an enzyme that breaks
down the cellulose so termites can absorb the
nutrients.

72.  Commonly called Algae
 Grouped into four major phyla
 All unicellular
 Autotrophic
 Absorb light with pigments (chlorophyll mainly)
 Some have accessory pigments, which absorb
wavelengths of light that chlorophyll cannot – increases
efficiency.

73.  Phlyum: Euglenophyta
 Characteristics:
 Two flagella, no cell wall, chloroplasts
 In low light, can become heterotrophic
 Very similar to zooflagellates
 Reproduction: asexual – binary fission
 Example:
 Euglena

74.  Phylum: Chrysophyta
 Characteristics:
 Chloroplasts contain bright yellow pigments,
making chloroplast appear golden.
 Store food as oil instead of starch
 Reproduction: asexual and sexual
 Examples:
 Yellow-green algae
 Golden-brown algae

75.  Phylum: Bacillariophyta
 Characteristics:
 Produce thin, delicate cell walls rich in silicon – the
main component of glass.
 Amazing array of shapes

76.  Phlyum: Pyrrophyta
 Characteristics:
 Half are photosynthetic, half are heterotrophic
 Two flagella
 Thick, external plates made of cellulose for
protection
 Many are luminescent (give off light) when agitated
 Pyrrophyta means “fire plants”
 Reproduction: asexual – binary fission
 Example:
 Gonyaulax – causes “red tides”
 (read on for more info)

77.  Common in fresh & salt water
 Important part of aquatic ecosystems
 Produce about half of the oxygen in the atmosphere
 Can cause serious problems
 Algal “blooms”
 Rapid population growth caused by increase in available
nutrients (sewage, fertilizer runoff from fields)
 Can have drastic effects on the fish and insects nearby
 Example – Dinoflagellates Gonyaulax and Karenia
 Blooms of these produce the “red tide” because they are red
in color
 Also produce a potentially dangerous toxin – filter-feeding clams
eat the dinoflagellates, and the toxins accumulate in the clam.
Eating clams and other shellfish with these toxins can cause
serious illness, paralysis, and even death in humans and fish.

78. Red Tide – La Jolla, California

80.  Multicellular
 Very similar to plants
 Live in water
 Grouped into three major phyla
 Sorted by their photosynthetic pigments

81.  Phylum: Rhodophyta
 Characteristics:
 Live almost entirely in salt-water
 Contain chlorophyll a and phycobilin (a red
pigment)
 Can live at great depths
 Play role in formation of coral reefs

82.  Phlyum: Phaeophyta
 Characteristics:
 Live almost entirely in salt water
 Contain chlorophyll a and c as well as fucoxanthin (a
brown pigment)
 Examples:
 Giant Kelp
 Rockweed (Fucus) – found on rocky coast of eastern
US

83. Kelp

84.  Phlyum: Chlorophyta
 Characteristics:
 Live in fresh water and salt water
 Unicellular or multicellular
 Food stored as starch
 Chlorophylls and accessory pigments similar to land plants
 Reproduction:
 Some sexual, some asexual
 Some have a diploid and haploid stage – called alternation of
generations
 Examples:
 Ulva (sea lettuce)
 Volvox

85.  Major food source for life in the oceans
 Major source of oxygen on Earth
 Algae offers many valuable chemicals
 Treat stomach ulcers, high blood pressure, arthritis;
make plastics, waxes, transistors, deodorants,
toothpaste, paint, lubricants, artificial wood
 Often eaten!
 Used in sushi, ice cream, salad dressing, pudding &
candy bars
 Can cause economic & health problems
 Toxins produced by “Red Tide” dinoflagellates

86.  Heterotrophic – absorb nutrients from dead or
decaying organic matter
 Lack chitin in their cell walls (fungi has chitin)
 Live on land and water
 Complex life cycles

87.  Phylum: Acrasiomycota & Myxomycota
 Characteristics:
 Spend most life as free-living cells similar to amoebas
 When food supply is limited, go through a complex
reproduction process:
 1) individuals send chemical signals that attract other cells of
same species
 2) Thousands of cells aggregate into a large slug-like colony
that begins to function as a single organism
 3) The colony migrates for several centimeters then stops to
produce a fruiting body which produces spores
 4) Spores are scattered and develop into the single amoeba-
like cells we started with.
 5) The cycle continues

89.  Phylum: Oomycota
 Characteristics:
 Thrive on dead or decaying organic matter in water
(and sometimes land)
 Not true fungi
 Often grows in a manner similar to fungus
 Reproduction:
 Complex lifecycle involving sexual and asexual
reproduction

90.  Important as recyclers of organic material
 Produce rich topsoil
 Cause plant diseases
 Mildew, blights of grapes and tomatoes
 Responsible for potato famine of 1846 in Ireland
 Destroyed potato crop – 1 million people died of
starvation, and another 1 million or so emigrated to the
US and other countries.

92.  All plants share the common ancestor of green
algae
 Plants have adapted to live on land
 Characteristics:
 The same photosynthetic pigments in similar
chloroplasts
 Cell walls with cellulose
 Food stored as starch
 Multicellular eukaryotes

93.  Four major groups based on differences in:
 Water-conducting tissues
 Seeds
 Flowers

94. Cladogram of the major plant types
Flowering
plants
Cone-bearing
plants
Ferns and
their relatives Flowers; Seeds
Mosses and Enclosed in Fruit
their relatives
Seeds
Water-Conducting
(Vascular) Tissue
Green algae
ancestor
(a protist)

95.  Non-Vascular
 lack vascular tissue for long-distance
transportation of water and solutes; lack true
roots, leaves or stems
 Vascular
 Have tissue specialized for the long-distance
transport of water and solutes through a plant;
have true roots, leaves and stems
 Much like a circulatory system

96.  Called Bryophytes
 Includes: Mosses & Liverworts
 Cannot retain water or deliver it to other parts of
the plant body
 Water must be absorbed directly from the
surrounding air or another nearby source
 Small, short, require water for sperm/egg union

97. Life cycle of Mosses
Protonema
Haploid (N) (young gametophyte)
Diploid (2N) Spores (N)
MEIOSIS Male
(N)
gametophyte
Female
gametophyte
Mature
sporophyte
(2N)
Capsule
(sporangium) Antheridia
Sperm Archegonia
Gametophyte Young (N)
(N) sporophyte
(2N)
Zygote
(2N)
Sperm
Gametophyte (N)
(N)
Egg
(N)
FERTILIZATION

98. Liverwort video portal

99.  90% of all modern plants have vascular tissue &
have true roots, leaves, & stems
 Characterized by the presence of a vascular system
composed of two types of specialized tissue
 Xylem – tissue that carries the water and dissolved
minerals upward in a plant
 made of dead cells
 Phloem – tissue conducts sugars and some water upward
and downward in a plant (sap)
 made of living cells
 Both xylem & phloem are distributed throughout
the roots, leaves & stem

101.  Roots
 Underground organs that absorb water and
minerals; anchor plant
 Leaves
 Photosynthetic organs that contain one or more
bundles of vascular tissue gathered into veins
made of xylem and phloem; contain pores
(stomata) for exchange of CO2 and O2
 Stems
 Supporting structures that connect roots and
leaves, carrying water and nutrients between
them.

102.  Seedless  Seeded
 Ferns produce spores  Plants produce male
(not seeds) by meiosis and female gametes
and store them in cases (pollen/egg) which join
on the underside of the to form an embryo. A
leaf (frond) protective seed coat
surrounds the embryo
 Once spores are
and provides
released, they
nourishment during
germinate into small
early stages of
plants if they reach
development.
moist ground
 Other examples
 Club mosses & horsetails

103. Undersides of fern fronds, showing
the bundles (sori) that contain spores.
Ferns do not produce flowers or seeds!

104. Life cycle of a fern
MEIOSIS
Sporangium
(2N) Haploid gametophyte (N)
Diploid sporophyte (2N)
Frond
Young
gametophyte
Spores (N)
Mature (N)
sporophyte
(2N)
Developing
sporophyte Mature
(2N) Antheridium gametophyte
(N)
Sperm
Gametophyte
(N) Egg
Sporophyte
embryo
(2N) Archegonium
FERTILIZATION

106.  Gymnosperms
 vascular plants that  Angiosperms
produce seeds  vascular plants that
lacking a protective produce seeds
fruit enclosed and
 gymnosperm means protected by a fruit
“naked seed”
 Are flowering plants
 Eg) conifers – firs,
 Oak, tulip,
spruce, pines, cedar
grass, corn, tomatoes

109. #1
#2

110.  Flowers– used in sexual reproduction of
angiosperms Stamen
Pistil
 Pistil (female part) Anther
Stigma
Style
 Ovary (produce eggs) Filament
Ovary
 Style (stalk that holds stigma)
 Stigma (sticky pollen collector)
 Stamen (male part)
 Anther (produce pollen)
 Filament (stalk that holds anther)
 Petals – attract pollinators
 Sepals – protect young flower
as it develops
Petal
Sepal

111.  Cuticle – layer of waxes on outer surface
that helps prevent loss of water
 Epidermis – one cell thick layer that secretes
the cuticle
 Stomata – openings for diffusion
 Guard cells – two cells on either side of
stomata that allow diffusion of CO2, oxygen
and water vapor into and out of plant for
photosynthesis

112. Guard cells Guard cells
Inner cell wall
Inner cell wall
Stoma
Stoma Open Stoma Closed

113. Cuticle
Veins
Epidermis
Xylem
Vein
Phloem
Epidermis
Stoma
Guard
cells

114. Relative numbers of plant species
Cone-bearing plants
760 species
(gymnosperms)
Ferns and Flowering
their relatives plants
11,000 species 235,000 species
(seedless (angiosperms)
vascular)
Mosses and
their relatives
15,600 species (nonvascular)

116.  Multicellular (more than 1 cell)
 Eukaryotic (cells have nucleus)
 Heterotrophic (can‟t make own food)
 No cell walls (only a membrane)

117.  Most animals have tissues
 Tissue - Group of cells that perform a similar
function
 Eg. muscular, connective, nervous
 All tissues arise from 3 embryonic
(“primitive”) layers
 Ectoderm (outer layer)
 Mesoderm (middle layer)
 Endoderm (inner layer)
 More primitive layers = more specialization
can occur during development

118.  With the exception of sponges, every animal is
symmetrical
 Two types of symmetry:
 Radial – any number of imaginary planes can be
drawn through the center, each dividing the body
into equal halves
 Eg) bike tire, cantaloupe, beach ball
 Bilateral – only a single imaginary plane can divide
the body into two equal halves
 Have a left/right, usually have front/back and
upper/lower

119. Bilateral Symmetry
Radial Symmetry
Posterior end
Anterior end
Plane of
symmetry
Planes of
symmetry

120.  Animals with bilateral symmetry usually show
cephalization.
 Cephalization – the concentration of sense
organs and nerve cells at the front end of the
body
 Cephal- Latin for “head”
 Cephalization allows animals to respond to the
environment more quickly and in more
complex ways than simpler creatures

121.  Invertebrates (95% of animal species)
 No backbone
 insects, sea stars, jellyfish, sponges, worms
 Vertebrates (5% of animal species)
 Have a backbone
 Fish, amphibians, reptiles, birds, mammals

122. Arthropod
Brain
Ganglia
Ganglia
Brain
Nerve
Cells
Flatworm
Cnidarian
Mollusk

123.  Kingdom
 Phlyum
 Class
 Order
 Family
 Genus
 Species
 In order of simple  complex

124.  The most simple animals
 These are the sponges
 No tissues, organs, mouth or gut
 Have a few specialized cells
 Have thousands of pores all over body

125. Water flow
Central cavity Choanocyte
Pores Spicule
Pore cell
Pore
Epidermal cell
Archaeocyte
 The movement of water through the sponge
provides a simple mechanism for feeding,
respiration, circulation, and excretion.

126.  Radial symmetry
 Have stinging tentacles arranged in circles
around mouth
 Specialized cells with barbs & poison
 Simplest animals with symmetry & specialized
tissues
 Hydras, jellyfishes, sea anemones & corals

127. Epidermis
Mesoglea
Gastroderm
Tentacles Mesoglea
Gastrovascular cavity
Mouth/anus
Mouth/anus
Gastrovascular Tentacles
cavity
Medusa
Polyp
 Life cycle of cnidarians includes the polyp and
medusa form
 Polyp – mouth points upward, usually sessile (attached
to bottom)
 Medusa – mobile, bell-shaped body with the mouth on
bottom

128. Structure of nematocyst – “Stinging cell” – for which Cnidarians get their name.

129.  Simple worms
 Includes: tapeworms and flukes
 Soft, worms with simple tissues and organ
systems
 Cephalization & bilateral symmetry
 Some are free-living, some are parasites

130. Eyespot Ganglia Freshwater flatworms have
simple ganglia and nerve cords
Head
Nerve that run the length of the body.
Gastrovascular cords The excretory system consists
cavity of a network of tubules
connected to flame cells that
Flatworms use a pharynx to suck remove excess water and cell
food into the gastrovascular cavity. Excretory wastes.
Digested food diffuses from the system
cavity into other cells of the body.
Eyespots in some Ovary
species detect light.
Testes
Mouth Pharynx
Most flatworms are
hermaphrodites, having male
reproductive organs (testes)
and female reproductive organs
(ovaries) in the same organism.
Flame cell
Excretory
tubule

132.  Earthworms, leeches & more
 Have segmented bodies
 Complex organ systems

133. Anus
Setae
Body segments
Gizzard Crop Dorsal
blood vessel
Clitellum
Mouth
Brain
Ganglion
Circular muscle
Ventral
blood vessel
Longitudinal Nephridia Ganglia Ring Reproductive
muscle vessels organs

135. Annelid or human?

136.  Mollusks – snails, slugs, clams, squid, octopi
 Soft-bodied animals
 Usually have internal or external shell
 All have a body plan with 4 major parts:
 Foot, mantle, shell, internal organs

137. Squid
Snail
Shell
Mantle cavity
Foot
Clam Gills
Early Digestive tract
mollusk

138. Nudibranchs
-see latest issue of
National Geographic
for amazing pictures

140.  Insects, crustaceans, spiders, horseshoe crabs,
scorpions, lobsters
 Segmented body, tough exoskeleton, jointed
appendages (legs & antennae)
 Complex tissues & organ systems
Famous ancient sea-dwelling arthropod: Trilobites!

142. Arthropod or human?

143.  Starfish, sea urchins, sea cucumbers, sea lilies,
sand dollars, brittle stars
 Spiny skin, internal skeleton, suction-cuplike
tube feet
 Usually 5-part radial symmetry

146.  Vertebrates (backbone)
 (exception: tunicates and lancelets)
 Backbone consisting of individual segments
called vertebrae
 We will look at the major classes

147.  Sharks, rays, skates
 Skeletons made of cartilage, not bone
 Teeth are made of bone!

148.  Bony fishes
 Skeletons made of bone

149. 1) Agnatha
Jawless fish
Ex. Lamprey, hagfish

150.  Amphibians! (salamanders, frogs, toads)
 Water & Land life stages
 Breathes with lungs as adult
 A lungless frog has been found (April „08)
 Moist skin with mucous glands
 Lacks scales & claws

151.  Snakes, turtles, lizards
 Dry, scaly skin
 Lungs
 Terrestrial (land) eggs
 Ecotherms

152.  Birds!
 Endotherms (regulate own body temp)
 Feathers
 2 legs covered with scales
 Front limbs modified into wings

154.  Mammals!
 HAIR
 MAMMARY GLANDS (produce milk)
 Breathe air

155. Chinese
Pangolin
Nine-Banded
Armadillo
Common
Echidna
Giant Anteater
Aardvark