1. Introduction to animals

2. Characteristics of Animals
All multicellular
Eukaryotes (cells with nucleus & organelles)
No cell wall
Ingestive heterotrophs (take in food and internally digest it)

3. Lions Feeding (Ingestion)

4. Support Systems Have some type of skeletal support
Endoskeleton inside and made of cartilage &/or bone
Exoskeletons found in arthropods
Cover the outside of the body
Limit size
Must be molted making animal vulnerable to predators

5. Cicada Molting Exoskeleton

6. Movement
Animals such as sponges may be sessile (attached & non-moving)
Animals that move very little are said to be sedentary (clam)
Animals that can move are motile
Have muscular tissue to provide energy for movement

7. SESSILE
SEDENTARY
Chiton
Sponge
MOTILE
Cheetah

8. Reproduction in Animals
All animals are capable of sexual reproduction

9. Leeches Exchange Sperm During Mating

10. Mating and Mating Behaviors
Female
Beetles Mating
Young
Courtship
Male
Mating and Mating Behaviors

11. Levels of Organization
Molecule or compound
Atom
Organelle
Levels of Organization
CELL
Life begins
Tissue
Organ
Organ system
Organism

12. Levels of Organization
animals show these levels – cell, tissue, organ, and organ system
Sponges are the ONLY animals that have just the cellular level
Cells may specialize (take own different shapes and functions)

13. Surfaces (Most Animals)
DORSAL
Back or upper surface
POSTERIOR
Tail or hind end
ANTERIOR
Head or Front
VENTRAL
Belly or lower surface

14. Body Symmetry
Symmetry is the arrangement of body parts around a central plane or axis
Asymmetry- no symmetry (sponges)

15. Body Symmetry
Radial symmetry occurs when body parts are arranged around a central point
Most animals with radial symmetry are sessile (attached) or sedentary (move very little)

17. Body Symmetry
Bilateral symmetry is when animals can be divided into equal halves
Organisms will have right and left sides mirror images of each other
Most complex type of symmetry

18. Body Symmetry Animals with bilateral symmetry are usually motile
Animals have an anterior and posterior ends
Show cephalization (concentration of sensory organs on the head or anterior end)

20. Body Symmetry

21. Tissues
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22. Tissue Development
Zygote (fertilized egg) undergoes rapid cell divisions called cleavage
Forms a hollow ball of cells called the blastula
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23. Blastula A hollow ball of cells
The blastocoel is the center cavity of the blastula with 1 germ layer (blastoderm)
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24. Germ Layers Form tissues, organs, & systems NOT present in sponges
Ectoderm (outer) – forms skin, nerves, sense organs
Endoderm (inner) – forms digestive, respiratory
Mesoderm (middle) – forms muscles, excretory, bones, circulatory

25. Body Layers Sponges have NO tissues or organs, only specialized cells
Cnidarians like jellyfish & coral have only two body layers & one body opening (mouth/anus) into gastrovascular cavity
Cnidarians have outer epidermis & inner gastrodermis with jelly-like mesoglea between the layers
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27. Body Cavities

28. Coelom - Body Cavity
Internal body cavity fully lined with mesoderm (coelomates)
Body organs suspended in this cavity
Eucoelomates – “true” coelom vertebrates & some invertebrates

29. Coelom - Body Cavity
Acoelomate animals have solid bodies filled with cells
Acoelomate animals include sponges, cnidarians, & flatworms

30. Coelom - Body Cavity
Pseudocoelomate animals (roundworms) have a functional body cavity NOT fully lined with mesoderm (ex. nematodes)

31. Images from: http://www.geocities.com/animalbio/biology/DIGESTIO.gif
Digestive Systems
Only one opening (two way): FOOD IN and WASTE OUT through same opening

32. Digestive Systems
Animals with a two openings (one- way digestive system have a mouth and an anus
Food enters the mouth, continues in one direction through the digestive tract, and wastes leave through the anus
Most efficient
Includes annelids, arthropods, & vertebrates

33. One-Way Digestion
Mouth
anus

34. Circulatory Systems Transports oxygen & nutrients to cells
Carries away wastes & carbon dioxide from cells
Sponges, cnidarians, & flatworms do NOT have circulatory systems

35. Circulatory Systems
In closed circulation, blood remains inside blood vessels until it reaches cells (annelids & vertebrates)
In open circulation, blood is pumped out of blood vessels to bathe tissues in the body cavity (arthropods & mollusks)

36. Closed
Circulation
Open Circulation

37. Invertebrate groups

39. Characteristics of Invertebrates
Simplest animals
Contain the greatest number of different species
Most are aquatic (found in water)
Do NOT have a backbone
Includes sponges, cnidarians, flatworms, roundworms, annelids, mollusks, arthropods, and echinoderms

40. Sponge - Porifera
Osculum of Sponge

41. More Cnidarians
Brain Coral
Red jellyfish

42. Flatworms - Platyhelminthes
Marine Flatworm
Planarian

43. Roundworms (Nematoda) and Segmented Worms (Annelida)
Nematode
Leech (segmented worm)

44. Mollusca (With and Without Shells)
snail
scallop
octopus
nudibranch
nautilus

45. Arthropoda (insects, spiders, crustaceans, horseshoe crab)
crayfish
Horseshoe crab
Dung beetle

46. Echinoderms starfish Sea fan (crinoid) Brittle star Sand dollar
Sea cucumber

48. Vertebrata More complex animals
have a backbone made up of individual bones called vertebrae
From simplest to most complex, the phylum includes: fish, amphibians, reptiles, birds, and mammals

49. Vertebrata Vertebrates have endoskeletons (internal)
Some vertebrates have skeletons of cartilage (sharks, rays, and skates)
Other vertebrates have skeletons of bone and cartilage (reptiles, birds, & mammals)

50. Bone & Cartilage in Fetus

51. Fish
lancelet
ray
damselfish
anglerfish

52. Amphibia
salamander
toad
frog
newt

53. Reptilia
Turtle
Snake
Lizard
Alligator

54. Birds - Aves
hummingbird
ostrich
lovebirds

55. Mammalia

56. That’s all folks! Study for your test! Introduction to Animals
Section 18-1 and 26-1 in your text
Classification

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