the animal kingdom animal kingdom - ednet.ns.cahrsbstaff.ednet.ns.ca/t_white/biology11/unit 2 -...
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The Animal Kingdom Animal Kingdom
Phylums:
1. Sponges
2. Cnidaria – Jelly Fish, Hydra
3. Flatworms – Flukes, Tapeworms
4. Roundworms - Hookworms
5. Segmented Worms - Earthworms
6. Rotifera - Rotifers
7. Mullusca – Snails, Clams, Squid
8. Arthropoda – Insects, Crabs, Spiders
9. Echinodermata – Starfish, Sea Cucumber
10.Chordata – Fish, Amphibians, Reptiles, Birds, Mammals
Characteristics of All Animals
• 1) Eukaryotic
• 2) Multi-Celled
• 3) Heterotrophic
Major Characteristics Used To Classify
Animals
• 1) Body Organization
• 2) Number of Body Layers
• 3) Body Symmetry
• 4) Digestive Tract of Guts
• 5) Coelom or Body Cavity
Major Characteristics Used To Classify
Animals
• 1) Body Organization:
– Have Tissues
– Tissues Organized into Organs
– Have Organ Systems
• 2) Number of Body Layers:
– Germ Layers: layers of cells in embryo that give rise to
specific tissues in the adult.
– 3 Germ Layers:
• A) Ectoderm (Ecto – outside) – develops into Skin & Nervous
System (some animals – scales, feathers, hair, nails, etc)
• B) Endoderm (Endo – inner) – develops into lining of gut.
• C) Mesoderm (Meso – middle) – between Ecto & Endoderm.
Develops into circulatory system, reproductive system,
excretory system & muscular system.
• 3) Body Symmetry:
– Radial Symmetry: Ex: Jelly fish & Star Fish
– - Can be cut many different
– directions, & all parts look
– the same.
– - No region leads meaning slow
– movement.
• 3) Body Symmetry – Coninued
– Bilateral Symmetry
– - Can be cut on one plane only
– into 2 same halves.
– - Defined Head or Anterior End
– - Since one end enters area
– before other, nerve cells are
– concentrated in anterior
(head)
– - Called Cephalization –
– concentration of nerve cells in Anterior End.
– Cephalization warns of danger or food – helps
animals that move forward.
• 4) Digestive Tracts or Guts:
– Gut: When the organism only has on opening.
The food and wastes enter and leave through the
same opening.
– Digestive Tract: When the organism has 2
openings. One for taking food in (mouth) and the
other for the release of waste products (anus).
• 5) Coelom or Body Cavity:
– A) Acoelom: lower invertebrates without a body
cavity.
– B) Pseudocoelom: some invertebrates don’t have
a coelom, but do have a cavity NOT lined with the
Peritoneum.
– 5) Coelom or Body Cavity Continued:
– C) Coelom: a body cavity filled with fluid inside
the body, lined with a layer of cells called
PERITONEUM.
– Coelom develops from the embryo’s Mesoderm.
– In all Vertebrates and Higher Invertebrates.
– Peritoneum not only lines the Coelom, but the
organs and holds them in place.
Worms
• Phylum:
• 1) Platyhelminthes – Flatworms
• 2) Nematoda – Roundworms
• 3) Annelida – Segmented worms
Platyhelminthes – Flatworms
• Invertebrates
• Acoelomates – no body cavity or coelom.
• Bilateral Symmetry – most primitive animal to
have bilateral symmetry.
• Have a Mesoderm, not found in simpler
organisms.
• Have true organs and simple organs systems
(digestive & excretion)
Free-Living Flatworms
Free – Living Flatworm
• Planaria – best known free-living flatworm
• Live in Moist, Fresh or Salt water.
• Small – less then 1 cm long, with some as long as 60 cm.
• Gut – mouth is where food enters and leaves.
• Nerve Tissue in Anterior like primitive brain.
• Have Eyespot – can sense light and chemical sense to find food.
• Hermaphroditic: but need 2 worms to reproduce. (Sexual)
• Asexual – by growing new worms from fragments.
Parasitic Flatworms
Parasitic Flatworms
• Live inside or outside organisms.
• Fluke & Tapeworm most common.
• Don’t have sensory receptors because they live inside organisms.
• Reduced or No Digestive System: Most feed off digested food of host so don’t need digestion themselves. Others will feed off host itself and needs to digest host cells.
• This leave room for very specialized Reproductive organs.
• 1 Tapeworm can produce over 100,000 eggs in life time.
Tapeworm Life Cycle
Tapeworm Lifecycle Nematoda – Round Worms
Nematoda – Round Worms
Nematoda – Round Worms
• Pseudocoelom – body cavity but no Peritoneum lining.
• Simplest Organisms withComplete Digestive Tracts.
• Most are free-living, cause no harm, but some are parasitic and cause lots of problems to plants and animals.
• Have Anterior Ganglion (nerve cluster) with lateral or ventral nerve cord along body.
• No respiratory or circulatory system.
• Most parasitic of all animals, makes them the most feared.
Ascaris Life Cycle
Annelida – Segmented WormsSegmented Worms
• Have Segmented body
• Earthworms, red worm & leeches
• Simplest to have Coelom
• Have Organ Systems – digestive, circulatory,
reproductive, excretion & coordination.
• Segments allow for movement and flexibility.
Segmented Earthworm
• Has brain and nerve cord down length of body
• Eat soil with dead organisms – decompose
• Form tunnels in soil for aeration and drainage
that is great for plants.
• Hermphroditic – but need 2 worms, both
produce eggs and lay them in a cocoon.
• Movement by Peristalsis using circular and
long muscles along with Setae (bristles) as
anchors.
Arthropods
• Largest phylum of the Animal Kingdom with
about 1,000,000 species, about 90% of all
known Animal Species.
• Include: spiders, mites, ticks, crabs, lobsters,
barnacles & scorpions.
• They are found in all habitats on Earth.
Arthropod Body
• Arthropods evolved from segmented species.
• The segments have fused together to form 3
areas:
• 1) Head In Many Species, these are
• 2) Thorax fused to form CEPHALOTHORAX
• 3) Abdomen
• Each segment performs a specialized function
Body Arthropod Characteristics
• Exoskeleton (cuticle): the hard, outer shell
used for protection and allow them to move.
• Cuticle made of Chitin. When thick if very
tough like lobster shell. When thing, very
flexible like the wing of a grasshopper.
• The inner layer of the Exoskeleton covers the
whole body, even across joints to keep the
organs in place and allow movement.
• Exoskeleton can’t grow, so arthropod must
Moult shell to grow larger.
More Characteristics
• Primitive Arthropods have a nervous system
similar to the annelids.
• Advanced Arthropods have a larger brain
allowing for more complex behaviour and
detection from senses such as Crabs and Bees.
Sensory Organs
Sensory Organs
• Eyes: very primitive, have few photoreceptors
to produce basic image.
• Antennae: touch when light levels too low to
see.
• Ears: primitive membrane over openings in
cuticle for hearing.
• Projections or Pits: over exoskeleton to sense
touch from predators or chemical responses.
More Characteristics
• Open Circulatory System: Have heart to move
blood around to brain and body. They don’t
have arteries for blood to move around in,
blood flows through Hemocoel (open spaces).
The organs are oxygenated by bathing in the
blood, not by capillaries.
More Characteristics
• Digestive System made of 3 parts:
• 1) Foregut: Mouth -> Esophagus -> Crop/Gizzard
• 2) Mudgut: Stomach where digestion complete
• 3) Hindgut: Intestine to Anus
Ecological Role of Arthropods Ecological Role of Arthropods
• Positive:
– Food source for many organisms.
– Some pollinate plants, including fruits and vegetables.
• Negative:
– Some (insects) compete for same food source as other organisms (humans) (harvests)
– Barnacles, Termites & Carpenter Ants eat at structures.
– Some transmit diseases (mosquitoes, ticks, fleas)