2. Symmetry As previously stated sponges are asymetrical – this means that in whatever plane you cut them their bodies will NOT be equal As previously stated sponges are asymetrical – this means that in whatever plane you cut them their bodies will NOT be equal Jelly fish (Cnidaria) and star fish (Echinoderms) show radial symmetry (like spokes on a wheel) this means that you can cut the body in any plane and have equal sides Jelly fish (Cnidaria) and star fish (Echinoderms) show radial symmetry (like spokes on a wheel) this means that you can cut the body in any plane and have equal sides Higher animals show bilateral symmetry 0 this means that the body can be cut in only one plane and have equal left and right sides Higher animals show bilateral symmetry 0 this means that the body can be cut in only one plane and have equal left and right sides

3. Animals Can Also Be Arranged by the Arrangement of Their Embryonic Cell Layers

4. Embryonic (Germinal) Layers Animals whose cells are arranged into two embryonic layers, an outer ectoderm and an inner endoderm are called diploblastic Animals whose cells are arranged into two embryonic layers, an outer ectoderm and an inner endoderm are called diploblastic Often an undifferentiated layer of cells is found between these two layers and is called the mesoglia Often an undifferentiated layer of cells is found between these two layers and is called the mesoglia This type of arrangement is found in cnidarians This type of arrangement is found in cnidarians

5. Embryonic (Germinal) Layers Animals that have a third embryonic layer located between the ectoderm and the mesoderm are called triploblastic Animals that have a third embryonic layer located between the ectoderm and the mesoderm are called triploblastic This layer of tissue is called the mesoderm This layer of tissue is called the mesoderm Platyhelminthes to chordates are all triploblastic Platyhelminthes to chordates are all triploblastic

7. What Becomes of these Layers? The Endoderm forms the stomach, intestines, lungs, pancreas, bladder, trachea and thyroid gland The Mesoderm forms the muscle, cartilage, urinary tract (not including bladder), heat, spleen, dermis and notochord The Ectoderm forms the hiair, nails, lens of the eye, sweat and sebacious glands, cornea, and the enamel of the teeth

8. The Animal Kingdom – Pt-2 Classification and Organization Dr. Jim Whitfield

9. Coelom The presence or absence of a cavity between the body wall and the gut wall is very important in classification The presence or absence of a cavity between the body wall and the gut wall is very important in classification

10. Coelom The body cavity id called the COELOM The body cavity id called the COELOM

11. Coelom The presence or absence of a cavity between the body wall and the gut wall is very important in classification The presence or absence of a cavity between the body wall and the gut wall is very important in classification The body cavity id called the COELOM The body cavity id called the COELOM Animals with a body cavity are called COELOMATES Animals with a body cavity are called COELOMATES

12. Coelom The presence or absence of a cavity between the body wall and the gut wall is very important in classification The presence or absence of a cavity between the body wall and the gut wall is very important in classification The body cavity is lined by mesoderm and called the COELOM The body cavity is lined by mesoderm and called the COELOM Animals with a body cavity are called COELOMATES Animals with a body cavity are called COELOMATES These include annelids, molluscs, arthopods, echinoderms, and chordates These include annelids, molluscs, arthopods, echinoderms, and chordates

13. Coelom In some animals the mesoderm is scattered in pouches throughout the endoderm and ectoderm. In some animals the mesoderm is scattered in pouches throughout the endoderm and ectoderm.

14. Coelom This type of body cavity is called a pseudocoelom This type of body cavity is called a pseudocoelom Animals with this type of body are called pseudocoelomates Animals with this type of body are called pseudocoelomates Examples of this are the Aschelminthes (formally part of the platyhelminthes) Examples of this are the Aschelminthes (formally part of the platyhelminthes)

15. Coelom Animals in which the body cavity is completely absent are called ACOELOMATES Animals in which the body cavity is completely absent are called ACOELOMATES

16. Coelom Examples are Platyhelminthes Examples are Platyhelminthes

17. Segmentation In some animals such as earthworms the body is divided both internally and externally into segments. Many of these segments have repeating organs this pattern of organization is called METAMERISM In some animals such as earthworms the body is divided both internally and externally into segments. Many of these segments have repeating organs this pattern of organization is called METAMERISM

18. Notochord The notochord is derived from mesoderm. It forms on the dorsal side of the organism (Back) The notochord is derived from mesoderm. It forms on the dorsal side of the organism (Back) Animals with a notochord are called chordates Animals with a notochord are called chordates Notochord forming in A chick embryo

19. SUMMARY OF ORGANIZATION

20. Phylum - Porifera The porifera are marine, asymmetrical animals commonly known as sponges The porifera are marine, asymmetrical animals commonly known as sponges

21. Phylum - Porifera The porifera are marine, asymmetrical animals commonly known as sponges The porifera are marine, asymmetrical animals commonly known as sponges Sponges have a water transport or canal system. Water enters through tiny pores called ostia in the body wall and enter into the spongocoel, or central cavity, it finally exits though the osculum. Sponges have a water transport or canal system. Water enters through tiny pores called ostia in the body wall and enter into the spongocoel, or central cavity, it finally exits though the osculum.

22. Phylum - Porifera The porifera are marine, asymmetrical animals commonly known as sponges The porifera are marine, asymmetrical animals commonly known as sponges Sponges have a water transport or canal system. Water enters through tiny pores called ostia in the body wall and enter into the spongocoel, or central cavity, it finally exits though the osculum. Sponges have a water transport or canal system. Water enters through tiny pores called ostia in the body wall and enter into the spongocoel, or central cavity, it finally exits though the osculum. This pathway is important in food gathering, repiratory exchange and removal of waste This pathway is important in food gathering, repiratory exchange and removal of waste

23. Phylum - Porifera Choanocytes (Collar cells) are specialized cells which contain a central flagellum which beats in unison help move the water and food through the spongocoel Choanocytes (Collar cells) are specialized cells which contain a central flagellum which beats in unison help move the water and food through the spongocoel Digestion is intracellular Digestion is intracellular The body is supported by a skeleton made up of spicules or spongin fibers. These also serve to deter predators The body is supported by a skeleton made up of spicules or spongin fibers. These also serve to deter predators Spicules are composed of calcium carbonate and spongin is composed of modified collagen secreted by sponogcytes Spicules are composed of calcium carbonate and spongin is composed of modified collagen secreted by sponogcytes

24. Phylum - Porifera Sponges are hermaphrodites – The sexes are not separate Sponges are hermaphrodites – The sexes are not separate Sponges reproduce asexually via fragmentation and sexually via the formation of gametes (egg and sperm) Sponges reproduce asexually via fragmentation and sexually via the formation of gametes (egg and sperm) Fertilization occurs internally Fertilization occurs internally Sponges have a larval stage morphologically distinct from the adult stage Sponges have a larval stage morphologically distinct from the adult stage

26. Phylum – Cnidaria Coelenterata Cnidarians are aquatic, sessile or free swimming, radial symmetrical animals Cnidarians are aquatic, sessile or free swimming, radial symmetrical animals The name is derived from specialized cells called cnidocytes which contain stinging capsules called nematocytes The name is derived from specialized cells called cnidocytes which contain stinging capsules called nematocytes

28. Phylum – Cnidaria Coelenterata Cnidarians are diploblastic and exhibit tissue level of organization Cnidarians are diploblastic and exhibit tissue level of organization Cnidarians have a central gastro-vascular cavity with a single opening called a hypostome. The hypostome is surrounded by tentacles to help bring in food Cnidarians have a central gastro-vascular cavity with a single opening called a hypostome. The hypostome is surrounded by tentacles to help bring in food Some cnidarians (corals) have a skeleton composed of calcium carbonate Some cnidarians (corals) have a skeleton composed of calcium carbonate

29. Phylum – Cnidaria Coelenterata Cnidarians have two body types called the polyp and the medusa Cnidarians have two body types called the polyp and the medusa The polyp is sessile and the medusa is free swimming. Cnidarians exhibit alternation of generations. This means that the polyps produce the medusa asexually produce polyps sexually

30. Phylum – Ctenophora Coelenterata Ctenophora are marine, radial symmetrical diploblastic organisms exhibiting tissue level of organization. Ctenophora are marine, radial symmetrical diploblastic organisms exhibiting tissue level of organization. They are often referred to as sea walnuts or comb jellies They are often referred to as sea walnuts or comb jellies The body contains external rows of comb plates that help with locomotion The body contains external rows of comb plates that help with locomotion

31. Phylum – Ctenophora Coelenterata Ctenophora exhibit bioluminescence (the ability to emit light) Ctenophora exhibit bioluminescence (the ability to emit light) All reproduction is sexual with external fertilization All reproduction is sexual with external fertilization

32. Ctenophora

33. Phylum - Platyhelminthes Platyhelminthes or flatworms are bilaterally symmetrical, triploblastic, acoelomates that exhibit tissue level of organization Platyhelminthes or flatworms are bilaterally symmetrical, triploblastic, acoelomates that exhibit tissue level of organization Most are endoparasites (many found in humans) Most are endoparasites (many found in humans) Many use hooks and suckers to absorb nutrients directly from the host Many use hooks and suckers to absorb nutrients directly from the host Specialized cells called flame cells help with osmoregulation and excretion Specialized cells called flame cells help with osmoregulation and excretion

34. Phylum - Platyhelminthes Platyhelminthes are hermaphrodites with internal fertilization and development Platyhelminthes are hermaphrodites with internal fertilization and development Many members of the phlya (such as planaria) show high degrees of regeneration Many members of the phlya (such as planaria) show high degrees of regeneration

35. Tapeworms Flukes Planaria

36. Phylum – Aschelminthes Nematodes Nematodes are roundworms (refers to the shape of their body in cross section) Nematodes are roundworms (refers to the shape of their body in cross section) Nematodes may be free living or parasitic, aquatic or terrestrial Nematodes may be free living or parasitic, aquatic or terrestrial Nematodes exhibit organ level organization, they have bilateral symmetry, with a triploblastic body Nematodes exhibit organ level organization, they have bilateral symmetry, with a triploblastic body They are pseudocoelomates with a complete digestive tract and a muscular pharynx that pushes food into the esphagus They are pseudocoelomates with a complete digestive tract and a muscular pharynx that pushes food into the esphagus

37. Phylum – Aschelminthes Nematodes Waste is removed through excretory pores in the body Waste is removed through excretory pores in the body Sexes are separate (Dioecious) with the females generally being larger Sexes are separate (Dioecious) with the females generally being larger Fertilization is internal and development may be direct or indirect Fertilization is internal and development may be direct or indirect

38. Phylum – Aschelminthes Nematodes Over 25,000 species have been described Over 25,000 species have been described Examples include: Hookworms, whipworms, pinworms, dirophilaria (heart worms) and trichinella Examples include: Hookworms, whipworms, pinworms, dirophilaria (heart worms) and trichinella Trichinella is the worm that causes trichinosis Trichinella is the worm that causes trichinosis

39. Phylum - Annelida Annelids are fairly complex Annelids are fairly complex Annelids may be marine or terrestrial, they are mostly free living (leeches are an exception) They are triploblastic, coelomates with bilateral symmetry and and organ level organization. Annelids may be marine or terrestrial, they are mostly free living (leeches are an exception) They are triploblastic, coelomates with bilateral symmetry and and organ level organization. There body surfaces are distinctly divided into segments or metameres There body surfaces are distinctly divided into segments or metameres

40. Phylum - Annelida Alternating circular and longitudinal muscles help with locomotion – This is an example of a hydrostatic skeleton Alternating circular and longitudinal muscles help with locomotion – This is an example of a hydrostatic skeleton

41. Phylum - Annelida Aquatic annelids have specialized appendages called parapodia to help with swimming Aquatic annelids have specialized appendages called parapodia to help with swimming Annelids have a closed circulatory system Annelids have a closed circulatory system Annelids have nephridia. Nephridia come in pairs and act similarly to the kidney. They are important in osmoregulation and waste removal Annelids have nephridia. Nephridia come in pairs and act similarly to the kidney. They are important in osmoregulation and waste removal Annelids have a primitive brain called a ganglia that attaches to the ventral nerve among other things it can detect touch and temperature Annelids have a primitive brain called a ganglia that attaches to the ventral nerve among other things it can detect touch and temperature

42. Phylum - Annelida Annelids may be monoecious or dioecious Annelids may be monoecious or dioecious Reproduction is sexual Reproduction is sexual