Download Characteristics of Kingdom Animalia

Unit 3 – Kingdom Animalia
Characteristics of Kingdom Animalia
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Eukaryotic
Heterotrophic
Multi-cellular
Diploid Adult Life Cycle – Diplontic
Sexual Reproduction
Classification of Animals
1. Symmetry – Body form
- Asymmetrical – no organization
- Radially symmetrical – any plane passing through results in mirror images
- Bilaterally symmetrical – only one plane passing through results in mirror images.
2. Tissue layers (A tissue is made up of similar cells)
- Cellular level – no tissues (Sponges)
- Diploblastic – two layers (ectoderm and endoderm) (Jellyfish)
- Triploblastic – three layers (ecto, endo, and mesoderm) (Mesoderm develops into organs)
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A sponge exhibits asymmetry
A Hydra illustrates radial symmetry
Crayfish exhibit bilateral symmetry
** All animals with bilateral symmetry have Eyes, Head, and Brain
3. Body Plan
- No Body Plan (Sponges)
- Sac – nutrients and waste enter and exit the same opening
- Tube within a tube – complete digestive tract, mouth, and anus
4. Body Cavity
- Acoelomate – no body cavity (no body plan and sac are always acoelomate)
- Pseudo coelomate – body cavity with incomplete lining of mesoderm
- Coelomate – Body cavity with complete lining of mesoderm ** Pseudo coelomate and
coelomate always have tube within a tube
5. Segmentation – A body plan with a series of repeating units or segments. This leads to
specialization of body segments.
- Segmented
- Non segmented
6. Development
- Direct development – newborns resemble adults. No larval stage
- Metamorphosis – larval stage. Does not resemble adult.
Phylogenetic Tree of Life (Animals)
Phylum Porifera
The term “diagnostic” refers to a characteristic that is unique to an organism
Sponges - known as the “Have Nots”
 Asymmetrical
 Cellular level – no tissues
 No body plan
 Acoelomate (No body cavity or tube within a tube)
 Non-segmented
 Metamorphosis (larval stage)
 Asexual reproduction – Budding, Fragmentation, and gemmules
** Budding is by design. Fragmentation is by accident (ex. Breaking off and starting anew). Gemmules
are a survival mechanism like an endospore or cyst.
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Three distinctive types of cells
1. Collar cells (aka choanocytes)
- Provide reproduction and feeding
2. Epidermal cells (aka Pinacocyte) – On the outside
- Give it structure
- Embedded in them is endoskeleton – spicules
3. Amoeboid cells
- Carry food
- Transport between epidermal and collar cells
- Become gemmules
Feeding process in sponge
Types of Sponge Architecture
** Sponges produce both egg and sperm
(least complex to most)
Phylum Cnidaria
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Radial Symmetry (can chop in half and get equal parts)
Diploblastic – tissues, but only ectoderm and endoderm
Sac body plan (one opening for eating and excreting)
Acoelomate (no semblance of a body cavity)
Non-segmented
Metamorphosis – 3 different stages of metamorphosis
Mesoglia – “Jelly” between endoderm and ectoderm
- Is diagnostic of jelly fish
Nematocyst – stinging cells (How they feed)
- Have neurotoxins in them
Two adult stages – Polyp & Medusa
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Cnidarian (Aurelia) Body Forms
** Medusans reproduce
** Coral are colonial polyps only
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Phylum Platyhelminthes
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Flatworms
- Bilateral symmetry
- Triploblastic
- Sac body plan
- Acoelomates
- Non-segmented
Class Turbellaria
 Planaria
- Cephalization – head region
- Eye spots (light sensitive)
- Pharynx – feeding and excreting
- Ladder-type nervous system
- Three-part digestive system
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Class Trematoda
 Flukes
 Vertebrate parasites
 Schistosomes – Blood flukes
Class Cestoidea
 Tapeworms
- Lack mouth/digestive system
Phylum Nematoda
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Roundworms
- Bilateral symmetry
- Non-segmented
- Triploblastic
- Tube within a tube body plan
- Pseudo coelomates
- Direct development
- Separate sexes
- Cosmopolitan (everywhere)
Phylum Rotifera
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Rotifers
- Bilateral symmetry
- Triploblastic
- Tube within a tube body plan
- Pseudo coelomates
- Non-segmented
- Asexual reproduction – Parthenogenesis (unfertilized egg develops)
- Coelom
- Body cavity with a complete lining of the mesoderm
Coelom Advantages
- Body movement independent of internal organs
- Development and isolation of organ systems
- Hydrostatic skeleton
Embryo Development
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Protostomes
Deuterostomes
Zygote  Morula embryo  Blastocyst  Gastrulation (Process called cleavage)
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VERY IMPORTANT
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Protostomes
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Cleavage is spiral and determinate
“The cells know what they want to be when they grow up.”
Mouth at blastopore
Coelom formation – mesoderm arises near blastopore
- Examples: Mollusca, Annelida, Arthropoda, Tardigrada
Deuterostomes
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Cleavage is radial and indeterminate
- Allows for identical twins
- Stem cells
Blastopore becomes the anus
Coelom formation – Mesoderm arises away from blastopore 
- Examples: Echinodermata (Star Fish), Chordata
Phylum Tardigrada
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Bilateral symmetry
Segmented
Organ level – Triploblastic
Tube within a tube body plan
Coelomates
4 pair of legs; claws
Cuticle
Cryptobiosis (equivalent to endospores)
Class Heterotardigrada
 Armored cuticle
 Simple claws
Class Eutardigrada
 Thin cuticle
 Multiple claws
Phylum Mollusca
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Triploblastic
Tube within a tube body plan
Coelomate
Bilateral symmetry
Non-segmented
Metamorphosis development
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Three-part body plan
 Visceral mass – Internal organs
- Specialized digestive tract – unique to mollusks
 Mantle – Encloses visceral mass
- Secretes shell, develops into lungs/gills
 Foot – Muscular (many derivations)
- Locomotion/attachment
Class Bivalvia
Clams, Mussels, Oysters, Scallops
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Two-part, hinged shell
Suspension feeders
Foot – Attachment (extension of visceral mass)
Siphons
(1 is incurrent – 1 is excurrent)
Class Cephalopoda
Squid, Octopus, Nautilus, Cuttlefish
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Cephalization – Head-footed
Tentacles, Arms – Capture prey
Jet propulsion – Locomotion
Diversity
- Nautilus – External skeleton, shell
- Squid – Internal skeleton – Pen
- Octopus – No skeleton
Class Gastropoda
Snails and slugs
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Aquatic – Gills, Terrestrial – Lungs
Elongated, flattened foot – Locomotion
Radula – Feeding structure – Scraping, Boring
Torsion – Twisting of shell – Asymmetrical
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Phylum Arthropoda
Insects, Arachnids, and Crustaceans
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75% of all animal species fall within this phylum
Protostomes
Segmented – Three-part body plan
- Head, Thorax, Abdomen
Jointed exoskeleton – Molting
Metamorphosis development
Open-circulatory system (Blood is pumped into body but not through veins)
- Contain hemolymph instead of blood
Subphylum Uniramia
Insects, Centipedes, Millipedes
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March 27, 2012
** Uniramia means “one branch”
Walking appendages – Uniramous – legs only
Insects – 3 pairs of legs
Terrestrial
Head appendages
- One pair of antennae
- One pair of mandibles
- Pairs of maxillae, palps (aide in feeding)
Gas exchange via air tubes – Trachea (No lungs)
Subphylum Crustacea
Crabs, Lobsters, Crayfish, Shrimp
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All aquatic
Walking appendages – Biramous – Legs/Gills
Cephalothorax – Fused head/Thorax
Head appendage
- Two pair of antennae
- Mandibles and Maxillae
Subphylum Chelicerata
Spiders, Scorpions, Horseshoe crabs
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Cephalothorax – Fused head/Thorax
4 pairs of legs
Piercing mouthparts
Head appendages
- No antennae
- Chelicerae – Feeding
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Pedipalps – Sensory
Phylum Annelida
Segmented worms
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Protostomes
Segmented – Metamerism
Bilateral symmetry
Closed-circulatory system (like humans)
Metamorphosis development
Class Oligochaeta
Earthworms
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Setae – small lateral bristles (allow them to move)
Clitellum – reproducing structure
Detritovores – decaying organic material
Hermaphroditic – both sexes
Gas Exchange
Class Polychaeta
Marine segmented worms
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Parapodia – bundles of lateral bristles
Suspension feeders and protectors
Separate sexes
Gas exchange – through external structures
Class Hirudinea
Leeches
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No setae or parapodia
Suckers
Annuli – demarcations between segments
Clitellum – reproductive structure
Predators and parasites
Gas Exchange – diffusion through body wall
Phylum Echniodermata
Sea stars (aka starfish), Sea urchins, Sand dollars
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Deuterostomes
Bilateral symmetry
- 5-part radial symmetry as adults
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Triploblastic
Tube within a tube
Ventral mouth
Dorsal anus
5-part digestive system
Closed circulatory system
2 stomachs (one internal, one external)
External skeleton (spiny) called skeletal plate
** Water vascular system is diagnostic of echinoderms.
Sieve plate  various canals or “pipes”  Tube feet
The sieve plate pops up to allow water in. It leads to the various canals or “pipes.” It ends up with
thousands of tube feet, which allow them to move. The tube feet also have suction power.
Phylum Chordata
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Deuterostomes
March 29, 2012
Bilateral Symmetry
Segmented
Triploblastic
Tube within a tube
Cephalization (with few exceptions)
4-part body plan
1. Notochord – support and attachment (runs through trunk). It is a flexible rod-shaped body
found in embryos of all chordates. It is composed of cells derived from the mesoderm and
defines the primitive axis of the embryo. In some chordates, it persists throughout life as the
main axial support of the body, while in most vertebrates it becomes the vertebral body of
the vertebral column. The notochord is found ventral to the neural tube.
2. Nerve cord - The dorsal nerve cord is a hollow cord dorsal to the notochord. It is formed
from a part of the ectoderm that rolls, forming the hollow tube, compared to other animal
phyla, which have solid, ventral tubes. The dorsal nerve cord is later modified into the brain
and spinal cord. Dorsal nerve cord is mainly found in phylum Vertebrata.
3. Pharynx (Pharyngeal slits) are filter-feeding organs found in non-vertebrate chordates
(lancelets and tunicates) living in aquatic environments. Respiration and feeding. Pharyngeal
slits resembling gill slits are transiently present during the embryonic stages of tetrapod
development.
4. Post-anal tail
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Subphylum Cephalochordata
Lancelets (fish-like)
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Filter feeders
Subphylum Urochordata
Tunicates
Subphylum Vertebrata
 Vertebrates – “Backbone” of cartilage or bone
 Craniates (surrounds the brain)
Superclass Agnatha
Jawless fish (Ex. Lampreys, Hagfish)
Lampreys
Hagfish
Superclass Gnathostomata
Jawed animals
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Jaws evolved from 1st pair of gill supports
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Class Chondrichthyes
Cartilagenous fish (Ex. Sharks, Rays, Skates)
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Cartilage Endoskeleton
5-7 Uncovered gill slits
2-chambered heart (receiving atrium – giving ventricle)
Class Osteichthyes
Bony fish
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Bone endoskeleton
Covered gills – Operculum
2-chambered heart
2 pairs of ventral fins (these became the legs in other animals)
Lungfish is common ancestor to tetrapods (4 legged-animals)
Class Amphibia
Frogs, Toads, Salamanders
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Tetrapod – 4 limbs adapted from the paired ventral fins of bony fish
Reproduce in water
External fertilization
3-chambered heart
Class Reptilia
Snakes, Lizards, Turtles, Alligators
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Amphibian ancestor
Tetrapods
Dry, Scaly skin – molts
Amniote egg – shell, membranes
Can occupy anywhere on earth
Internal fertilization
3-chambered heart
Class Aves
Birds
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Common reptile ancestor
Amniote egg
Endothermic (Ability to regulate temperature)
Flight-related anatomy
- Wings – modified forelimbs
- Keeled breastbone – muscle attachment
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Beak (modified jaws)
4-chambered heart
Class Mammalia
 Reptile ancestor – Thecodont (Harry lizard)
 Endothermic
 Mammary glands
 Hair (warmth, protection)
 Large cranial capacity
Subclass Prototheria
Monotremes (egg-laying mammals)
Subclass Metatheria
Marsupials (birth is early)
Subclass Eutheria
Placentals
Order Primates
Lemurs, Monkeys, Apes, Humans
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Large brain
5 digits
Opposable thumbs
Family Hominidae
 Bipedalism
Homo sapiens
 Large cranial capacity
Kingdom – Animalia
Phylum – Chordata
Subphylum – Vertebrata – developed into spinal cord
Superclass – Gnathostomata (jaws)
Mammals – Hair & Mammary glands
Subclass – Euthenia (Placental)
Order – Primates
Family – Hominidae
Genus – Homo (Brain structure)
Specific Epithet – sapiens
Species – Homo sapiens
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