Chapter 28
Chapter 28
KINGDOM ANIMALIA
KINGDOM ANIMALIA
CHARACTERISTICS
CHARACTERISTICS
The following characteristics describe most animals: The following characteristics describe most animals: 1.
1. DiplDiploid oid multmulticelicellulalular r eukeukaryoaryotes.tes. 2.
2. CellCells are specis are specializalized and orged and organianized into tized into tissuessues orgas organs etcns etc.. !.
!. "ete"eterotrorotrophs thphs that inhat inhabit thabit the sea fre sea fresh wesh water anater and landd land.. #.
#. $ost ar$ost are capae capable of loble of locomocomotion ation at some stt some stage of tage of their liheir li%es.%es. &.
&. $ost can re$ost can respond aspond adapti%ely to dapti%ely to e'ternal se'ternal stimuli and timuli and ha%e weha%e well de%elopell de%eloped sense od sense organs anrgans andd ner%ous system.
ner%ous system. (.
(. $ost repro$ost reproduce seduce se'ually'ually with with large nolarge non)motile en)motile eggs anggs and small fd small flagellatelagellated sperms.d sperms. *.
*. The diploThe diploid zygote pid zygote produced broduced by fertilizatioy fertilization di%ides bn di%ides by mitotic dy mitotic di%isions resui%isions resulting in a lting in a ball ofball of cells that usually hollows out to become a blastula. +ponges are an e'ception.
cells that usually hollows out to become a blastula. +ponges are an e'ception. ,bout !
,bout !& phyla th& phyla the ma-ority oe ma-ority of which af which are in%ertebre in%ertebrates.rates.
CLASSIFICATION
CLASSIFICATION
ased on type of / ased on type of /
1.
1. ody ca%ody ca%ityity: : acoacoelomelomateate pseudo pseudocoelcoelomaomates coeltes coelomatomates.es. 2.
2. De%eDe%eloplopmentmental patteral pattern: proton: protostomstomes deutes deuteroserostometomes.s. !.
!. oody sydy symmemmetrytry: radi: radialal bila bilaterteral.al. Types of sectioning a specimen:
Types of sectioning a specimen:
•
• Sagittal section di%ides the body intoSagittal section di%ides the body into right and left artsright and left arts.. •
• Cross or trans!erse sectionCross or trans!erse section di%ides the body into di%ides the body into anterior and osterior artsanterior and osterior arts.. •
• Frontal section di%ides the body intoFrontal section di%ides the body into dorsal and !entral artsdorsal and !entral arts..
Coelom or body ca%ity is fluid)filled space located between the outer body wall and the digesti%e Coelom or body ca%ity is fluid)filled space located between the outer body wall and the digesti%e tube.
tube.
0erm layers: 0erm layers:
•
• ndoderm forms the lining of the digesti%e tract.ndoderm forms the lining of the digesti%e tract. •
• $esoderm forms most body structures: muscles bones etc.$esoderm forms most body structures: muscles bones etc. •
• ctoderm gi%es rise to the outer co%ering of the body and the ner%ous system ifctoderm gi%es rise to the outer co%ering of the body and the ner%ous system if
present3. present3. Dilo"lastic
Dilo"lastic animals cnidarians and ctenophores3 ha%e two germ layers. animals cnidarians and ctenophores3 ha%e two germ layers. Trilo"lastic
,nimals may ,nimals may be...be...
•
• Acoelo#ateAcoelo#ate: lack coelom or body ca%ity e.g. cnidarians ctenophores flatworms..: lack coelom or body ca%ity e.g. cnidarians ctenophores flatworms.. •
• $se%docoelo#ate&$se%docoelo#ate& coelom is partially lined with mesoderm e.g. roundworms rotifers.. coelom is partially lined with mesoderm e.g. roundworms rotifers.. •
• Coelo#ateCoelo#ate: coelom is completely lined with mesoderm.: coelom is completely lined with mesoderm.
,nimals ca
,nimals can be clasn be classified assified as rotosto#esrotosto#es if the blastopore de%elops into the mouth and if the blastopore de%elops into the mouth and de%terosto#es
de%terosto#es if it de%elops into the anus. if it de%elops into the anus.
Deuterostomes and protostomes ha%e different pattern of clea%age: Deuterostomes and protostomes ha%e different pattern of clea%age:
•
• Radial clea!age is characteristic of deuterostomes4Radial clea!age is characteristic of deuterostomes4 •
• Siral clea!age is followed by protostomes.Siral clea!age is followed by protostomes.
5rotostomes also ha%e a
5rotostomes also ha%e a deter#inatedeter#inate clea%age in which the fate of the embryonic cells is fi'ed clea%age in which the fate of the embryonic cells is fi'ed %ery early in de%elopment.
%ery early in de%elopment. Deuterostomes ha%e an
Deuterostomes ha%e an indeter#inateindeter#inate clea%age in which each cell keeps longer the capacity clea%age in which each cell keeps longer the capacity to de%elop into a full organism.
to de%elop into a full organism. Schi'ocoel(
Schi'ocoel( method of coelom formation is characteristic of protostomes. method of coelom formation is characteristic of protostomes. Deuterostomes follow the
Deuterostomes follow the enterocoel(enterocoel( pattern of coelom formation. pattern of coelom formation.
$H)L*M $ORIFERA $H)L*M $ORIFERA
1. $ulticellular4 body a loose aggregation of cells of mesenchymal origin. 1. $ulticellular4 body a loose aggregation of cells of mesenchymal origin. 2. ody with pores
2. ody with pores ostiaostia3 canals and chambers that ser%e for passage of water to the central3 canals and chambers that ser%e for passage of water to the central ca%ity
ca%ity songocoelsongocoel3 and out of the open end the3 and out of the open end the osc%l%#osc%l%#..
!. ,bout 6777 species ha%e been identified4 all are auatic and mostly marine. !. ,bout 6777 species ha%e been identified4 all are auatic and mostly marine. #. +ymmetry radial or none.
#. +ymmetry radial or none.
&. pidermis of flat pinacocytes4 most interior surfaces lined with flagellated collar cells &. pidermis of flat pinacocytes4 most interior surfaces lined with flagellated collar cells choanocytes3 that create water currents4 a gelatinous protein matri' called
choanocytes3 that create water currents4 a gelatinous protein matri' called #esoh(l#esoh(l which which contains amebocytes collencytes secrete collagen3 and skeletal elements spicules3.
contains amebocytes collencytes secrete collagen3 and skeletal elements spicules3. (. +keletal structure of calcareous Class Calcarea3 or siliceous crystalline spicules Class (. +keletal structure of calcareous Class Calcarea3 or siliceous crystalline spicules Class "e'actinellida3
"e'actinellida3 or or fibrillar collagen a protein fibrillar collagen a protein and often and often combined with %ariously modifiedcombined with %ariously modified collagen spongin3 fibrils Class Demospongiae3.
collagen spongin3 fibrils Class Demospongiae3.
*. 9o organs or true tissues4 cells form a loose association but there is di%ision of labor4 *. 9o organs or true tissues4 cells form a loose association but there is di%ision of labor4 digestion intracellular4 e'cretion and respiration by diffusion.
digestion intracellular4 e'cretion and respiration by diffusion.
8. eactions to stimuli apparently local and independent4 ner%ous system probably absent. 8. eactions to stimuli apparently local and independent4 ner%ous system probably absent. 6. ,ll adults sessile and attached to substratum.
17. ,se'ual reproduction by buds or gemmules and se'ual reproduction by eggs and sperm4 17. ,se'ual reproduction by buds or gemmules and se'ual reproduction by eggs and sperm4 most are hermaphroditic4 free)swimming ciliated lar%ae.
most are hermaphroditic4 free)swimming ciliated lar%ae. $H)L*M CNIDARIA
$H)L*M CNIDARIA
1. ntirely auatic4 some in fresh water but mostly marine. ,bout 17777 species. 1. ntirely auatic4 some in fresh water but mostly marine. ,bout 17777 species.
2. adial symmetry or biradial radial and bilateral3 symmetry around a longitudinal a'is with 2. adial symmetry or biradial radial and bilateral3 symmetry around a longitudinal a'is with oral and aboral ends4 no definite head.
oral and aboral ends4 no definite head.
!. Two basic body forms: polyp and medusa. !. Two basic body forms: polyp and medusa.
#. 'oskeleton or endoskeleton of chitinous calcareous or protein components in some. #. 'oskeleton or endoskeleton of chitinous calcareous or protein components in some. &. ody with two layers epidermis and gastrodermis4 with mesoglea
&. ody with two layers epidermis and gastrodermis4 with mesoglea dilo"lasticdilo"lastic34 mesoglea34 mesoglea with cells and connecti%e tissue in some
with cells and connecti%e tissue in some trilo"lastictrilo"lastic3.3. (.
(. Gastro!asc%lar ca!it( or coelenteronGastro!asc%lar ca!it( or coelenteron often branched or di%ided with septa3 with a single often branched or di%ided with septa3 with a single opening that ser%es as both mouth and anus4 e'tensible tentacles usually encircling the mouth opening that ser%es as both mouth and anus4 e'tensible tentacles usually encircling the mouth or oral region.
or oral region. *.
*. Cnidoc(tesCnidoc(tes stinging cells3 located in the epidermis and gastrodermis contain special stinging cells3 located in the epidermis and gastrodermis contain special stinging organelles called
stinging organelles called ne#atoc(stsne#atoc(sts4 nematocysts abundant on tentacles where they may4 nematocysts abundant on tentacles where they may form batteries or rings.
form batteries or rings.
8. 9er%e net with symmetrical and asymmetrical synapses4 some sensory organs4 diffuse 8. 9er%e net with symmetrical and asymmetrical synapses4 some sensory organs4 diffuse conduction.
conduction.
6. $uscular system epitheliomuscular type3 of an outer layer of longitudinal fibers at base of 6. $uscular system epitheliomuscular type3 of an outer layer of longitudinal fibers at base of epidermis and an inner one of circular fibers at base of gastrodermis4 modifications of this plan epidermis and an inner one of circular fibers at base of gastrodermis4 modifications of this plan in anthozoans such as separate bundles of independent fibers in the mesoglea.
in anthozoans such as separate bundles of independent fibers in the mesoglea.
17. eproduction by ase'ual budding in polyps3 or se'ual reproduction by gametes in all 17. eproduction by ase'ual budding in polyps3 or se'ual reproduction by gametes in all medusae and some polyps4 se'ual forms monoecious or dioecious4 planula lar%a.
medusae and some polyps4 se'ual forms monoecious or dioecious4 planula lar%a. 11. 9o e'cretory or respiratory systems.
11. 9o e'cretory or respiratory systems. 12. 9o coelomic ca%ity.
12. 9o coelomic ca%ity.
Class H(dro'oa
Class H(dro'oa ) $ost hydrozoans are marine and colonial in form and typically include both ) $ost hydrozoans are marine and colonial in form and typically include both the medusa and polyp stage in their life cycle. +ome howe%er ha%e no medusa stage and the medusa and polyp stage in their life cycle. +ome howe%er ha%e no medusa stage and some occur only as medusae and ha%e no polyp stage.
some occur only as medusae and ha%e no polyp stage. 'amples: "ydra ;belia.
'amples: "ydra ;belia. Class Sc(ho'oa
Class Sc(ho'oa ) Class +cyphozoa -ellyfishes3 includes most of the larger <-ellyfishes<. , ) Class +cyphozoa -ellyfishes3 includes most of the larger <-ellyfishes<. , few such as Cyanea may attain a bell diameter e'ceeding 2 m and tentacles (7 to *7 m long few such as Cyanea may attain a bell diameter e'ceeding 2 m and tentacles (7 to *7 m long but most range from 2 cm to #7 cm in diameter. Their polyp stage is absent or greatly reduced but most range from 2 cm to #7 cm in diameter. Their polyp stage is absent or greatly reduced and the medusae of
and the medusae of this class ha%e no %elum. this class ha%e no %elum. 'amples: ,urelia Cyanea.'amples: ,urelia Cyanea. Class Antho'oa
Class Antho'oa ) ,nthozoa means <flower animal< and anthozoans are indeed polyps with a ) ,nthozoa means <flower animal< and anthozoans are indeed polyps with a flowery appearance. They do not ha%e a medusa stage. ,nthozoans are all marine and are flowery appearance. They do not ha%e a medusa stage. ,nthozoans are all marine and are
found all o%er the world in %arious sizes and habitats. 'amples: +ea anemones corals sea found all o%er the world in %arious sizes and habitats. 'amples: +ea anemones corals sea fans.
fans.
$H)L*M CTENO$HORA $H)L*M CTENO$HORA 13
13 RO+S OF COM, $LATESRO+S OF COM, $LATES that gi%e this animals their name: Cten = 0reek for comb while that gi%e this animals their name: Cten = 0reek for comb while phero = to bear. +o Ctenophore means <bearer of combs<.
phero = to bear. +o Ctenophore means <bearer of combs<. 23
23 COLLO,LASTSCOLLO,LASTS which are sticky prey capturing structures analogous in their function to the which are sticky prey capturing structures analogous in their function to the nematocysts of the Cnidarians but actually not similar in their design.
nematocysts of the Cnidarians but actually not similar in their design.
!3 adially symmetrical like the Cnidarians but because of two long feeding tentacles that most !3 adially symmetrical like the Cnidarians but because of two long feeding tentacles that most Ctenophores ha%e they are only strictly symmetrical at two points so they are biradially
Ctenophores ha%e they are only strictly symmetrical at two points so they are biradially symmetrical.
symmetrical.
#3 Ctenophores ha%e real muscles which are beneath the epidermis. These are used to #3 Ctenophores ha%e real muscles which are beneath the epidermis. These are used to contract the tentacles and in beha%iors such as prey swallowing pharyngeal contractions contract the tentacles and in beha%iors such as prey swallowing pharyngeal contractions swallowing3 etc.
swallowing3 etc.
&3 They are the largest organism that uses cilia to mo%e. &3 They are the largest organism that uses cilia to mo%e.
(3 Tentacles euipped with adhesi%e glue cells that trap plankton. (3 Tentacles euipped with adhesi%e glue cells that trap plankton.
ACOELOMATES ACOELOMATES
$H)L*M $LAT)HELMINTHES $H)L*M $LAT)HELMINTHES 1.
1. ThrThree geee germ layrm layers ters tripriplobloblalastistic3.c3.
2.ilateral symmetry4 definite polarity of anterior and posterior ends. 2.ilateral symmetry4 definite polarity of anterior and posterior ends.
!.ody flattened dorso%entrally in most4 oral and genital apertures mostly on %entral surface. !.ody flattened dorso%entrally in most4 oral and genital apertures mostly on %entral surface. #. ody with multiple reproducti%e units in one class Cestoda3.
#. ody with multiple reproducti%e units in one class Cestoda3. &. pidermis may be cellular or syncytial ciliated in some3. &. pidermis may be cellular or syncytial ciliated in some3.
(. $uscular system of mesodermal origin in the form of a sheath of circular longitudinal and (. $uscular system of mesodermal origin in the form of a sheath of circular longitudinal and obliue layers beneath the epidermis or tegument.
obliue layers beneath the epidermis or tegument.
*. 9o internal body space acoelomate3 other than digesti%e tube4 spaces between organs filled *. 9o internal body space acoelomate3 other than digesti%e tube4 spaces between organs filled with parenchyma.
with parenchyma. 8.
8. Digesti%e Digesti%e system insystem incomplete complete gastro%asgastro%ascular typcular type3 absee3 absent in +nt in +ome4 e'ome4 e'tensi%ely tensi%ely branchedbranched.. 6.
6. 9er%ous sy9er%ous system consstem consisting of isting of a pair a pair of anteof anterior ganrior ganglia with glia with longitudlongitudinal ner%e inal ner%e cordscords connected by trans%erse ner%es and located in the parenchyma in most forms
connected by trans%erse ner%es and located in the parenchyma in most forms 17. +imple sense organs eyespots in some.
11. 'cretory system of two lateral canals with branches bearing flame cells protonephridia3 11. 'cretory system of two lateral canals with branches bearing flame cells protonephridia3 lacking in some forms.
lacking in some forms.
12. espiratory circulatory and skeletal systems lacking. 12. espiratory circulatory and skeletal systems lacking.
1!. $ost forms monoecious4 reproducti%e system comple' usually with well)de%eloped gonads 1!. $ost forms monoecious4 reproducti%e system comple' usually with well)de%eloped gonads ducts and accessory organs4 internal fertilization4 life cycle simple in free)swimming forms and ducts and accessory organs4 internal fertilization4 life cycle simple in free)swimming forms and those with single hosts4 complicated life cycle often in%ol%ing se%eral hosts in many internal those with single hosts4 complicated life cycle often in%ol%ing se%eral hosts in many internal parasites.
parasites.
Class T%r"ellaria
Class T%r"ellaria ) Turbellarians are mostly free)li%ing worms than range in length from & mm ) Turbellarians are mostly free)li%ing worms than range in length from & mm or less to &7 cm. >sually co%ered with ciliated epidermis they are typically creeping worms that or less to &7 cm. >sually co%ered with ciliated epidermis they are typically creeping worms that combine muscular with ciliary mo%ement to achie%e locomotion. The mouth is on the %entral combine muscular with ciliary mo%ement to achie%e locomotion. The mouth is on the %entral side. 'ample: Dugesia
side. 'ample: Dugesia Class Tre#atoda
Class Tre#atoda ) The trematodes are all parasitic flukes and as adults they are almost all ) The trematodes are all parasitic flukes and as adults they are almost all found as
found as internal parasites of internal parasites of %ertebrates. %ertebrates. 'amples: Clonorchis +chistosoma'amples: Clonorchis +chistosoma Class Cestoda
Class Cestoda ) The cestodes or tapeworms usually ha%e long flat bodies made up of many ) The cestodes or tapeworms usually ha%e long flat bodies made up of many reproducti%e units proglottids3 and ha%e no digesti%e system. They also ha%e a specialized reproducti%e units proglottids3 and ha%e no digesti%e system. They also ha%e a specialized structure called the scole' <holdfast<3 which is the organ by which they attach to their host. ?t is structure called the scole' <holdfast<3 which is the organ by which they attach to their host. ?t is usually pro%ided with suckers and often with hooks or spiny tentacles. 'amples: Taenia
usually pro%ided with suckers and often with hooks or spiny tentacles. 'amples: Taenia
$H)L*M NEMERTEA $H)L*M NEMERTEA
$embers of the phylum 9emertea are commonly called the ribbon worms. There are $embers of the phylum 9emertea are commonly called the ribbon worms. There are
appro'imately 677 known species most of that are benthic marine animals although there are appro'imately 677 known species most of that are benthic marine animals although there are a few freshwater and terrestrial species and some deep water species.
a few freshwater and terrestrial species and some deep water species.
CHARACTERISTICS CHARACTERISTICS 13
13 They arThey are acoee acoelomalomate flatte flattentened dorsoed dorso)%en)%entralltrally and ha%ey and ha%e circular longitudinal and dorso%entral muscles.
circular longitudinal and dorso%entral muscles. 23
23 ;ne de;ne defining fining charactecharacteristic of ristic of the nthe nemerteanemerteans is ts is the prehe presencesence of an e%ersible proboscis.
of an e%ersible proboscis. !3
!3 TubTube)we)withinithin)a)tu)a)tube bodbe body plan: ouy plan: outer bodter body wall and iny wall and inner ner digesti%e tract. Complete digesti%e system: mouth and anus. digesti%e tract. Complete digesti%e system: mouth and anus.
#3 Circulatory system with blood that tra%els through contractile %essels and may mo%e in either #3 Circulatory system with blood that tra%els through contractile %essels and may mo%e in either direction. There is no heart and the pumping of blood is aided by the muscular contractions of direction. There is no heart and the pumping of blood is aided by the muscular contractions of the body associated with mo%ement.
the body associated with mo%ement.
$SE*DOCOELOMATES $SE*DOCOELOMATES
5seudo = <false< 4 coelom = body ca%ity 5seudo = <false< 4 coelom = body ca%ity
The pseudocoelomate animals include the otifera 0astrotrichia @inorhyncha Aoricifera The pseudocoelomate animals include the otifera 0astrotrichia @inorhyncha Aoricifera 5riapulida 9ematoda 9ematomorpha ,canthocephala and ntoprocta.
$H)L*M N
$H)L*M NEMATEMATODAODA ,
, group of group of worms widworms widely distributeely distributed in the sd in the soil fresh aoil fresh and salt)wnd salt)water en%ironater en%ironments4 sca%ments4 sca%engersengers carni%ores and parasites.
carni%ores and parasites. CHARACTERISTICS CHARACTERISTICS
1. ody bilaterally symmetrical cylindrical in shape. 1. ody bilaterally symmetrical cylindrical in shape.
2. ody co%ered with a secreted fle'ible nonli%ing cuticle. 2. ody co%ered with a secreted fle'ible nonli%ing cuticle. !. Bluid in pseudocoel forms a hydrostatic skeleton.
!. Bluid in pseudocoel forms a hydrostatic skeleton. #. Complete digesti%e system.
#. Complete digesti%e system.
&.'cretory system consists of specialized cells andor canal system4 flame cell protonephridia &.'cretory system consists of specialized cells andor canal system4 flame cell protonephridia lacking.
lacking.
(. Circulatory system lacking. (. Circulatory system lacking.
*. +e'ual reproduction4 se'es separate. *. +e'ual reproduction4 se'es separate. 'ample: ,scaris 'ample: ,scaris $H)L*M ROTIFERA $H)L*M ROTIFERA CHARACTERISTICS CHARACTERISTICS
13 otifera deri%e their name from their characteristic ciliated crown or corona which gi%es the 13 otifera deri%e their name from their characteristic ciliated crown or corona which gi%es the impression of a rotating wheel when beating.
impression of a rotating wheel when beating.
23 The body is usually di%ided into a head trunk and foot. The head bears the corona the trunk 23 The body is usually di%ided into a head trunk and foot. The head bears the corona the trunk has a thickened cuticle with ridged plates and spines for defense and the foot often bears 1)# has a thickened cuticle with ridged plates and spines for defense and the foot often bears 1)# pro-ections called toes which are used for attachment.
pro-ections called toes which are used for attachment. #3
#3 5se5seududococoeloelomomate aate animnimalals.s. &3
&3 otiotifers arfers are <cele <cell constl constantant<: each m<: each membeember of a specr of a species isies is composed of the same number of cells.
composed of the same number of cells. (3
(3 "a%e a ne"a%e a ner%our%ous systes system with a ganm with a ganglioglion ner%n ner%es and aes and an eyen eye spot.
spot. *3
