Tuesday 22 December 2015


PHYLUM PLATYHELMITHES !!!
 


 

UNIQUE CHARACTERISTIC



 
 
 
 
  • In Greek means ‘flatworms’
  • Living in marine, freshwater & damp terrestrial habitats.
  • Flatworms are ciliated, soft-bodied animals
  • Mostly parasitic, live in at least 1 host
  • Others are free-living 




      -Germ layers : triploblastic,the mesoderm contributes to the development of muscles and reproductive organs
       -Body cavities : acoelomates (no body cavity)
       -Bilaterally symmetrical





  • Their bodies are  flattened between dorsal & ventral surfaces
  • Digestive system with single opening (has mouth but no anus)


  • Body muscle cannot be contracted
  • Locomotion : swimming 
  • Lack circulatory system
  • Gas exchange occurs by diffusion
  • Have an excretory and osmoregulatory system 
           -Use flame cells/ protonephridia located on the side branches
  • Simple nervous system
           -Eyespot can distinguish light from dark
  • Reproduction–sexual or asexual (regeneration)
    -Mostly are hermaphrodites (monoecious)

    Flatworm anatomy






     3 Classes of Platyhelminthes :
    1. Class Cestoda (tapeworm :Taenia sp.)






    • parasitic
    • adult worms live in vertebrates; digestive tract (Endoparasite)  
    • the body consists of: 
              i) head @ scolex
                 -with hooks or suckers to anchor the worm to the intestinal lining




    2. Class Trematoda (flukes, Fasciola sp.) 

     

     

     

     


    • Parasite on sheep, cattle and occasionally humans.
    •  The gland cells secrete materials which protect the parasite against the host’s antitoxin
    • Endoparasitic, living in bile ducts. 
    • Anaerobic respiration




    3.Class Turbellaria (planaria, Dugesia sp.)










     






    • Free living and ciliated with few parasitic forms 
    • They are mainly marines but can also be found in fresh water




    Life cycle of the pork tapeworm, Taenia solium










PHYLUM CNIDARIA !!!

 
 

UNIQUE CHARACTERISTICS 
 
  • In Greek means ‘stinging structures’                            
     
  • Most marine, few fresh water species
  •  e.g :Obelia sp.
  •  Eumetazoans (has true tissues)
  • Diploblastic 
    -2 well developed tissue layer
  1.  Inner gastrodermis/ endoderm
  2. Outer epidermis/ectoderm 
          *Gelatinous mesoglea between layers*


-Radial symmetry
-Acoelomate 
-Have reproductive,circulatory, and gastrovascular systems
-Possess both muscle and nerve cells






  • Exhibit dimorphism / polymorphism (i.e. two types body plan)
     a) Sessile polyps
            -2 types of polyp
    
                  * Reproductive polyp
                                          
                  * Feeding polyp : equipped with tentacles
 
                b) Motile medusa










  • Medusa : free swimming adult stage that reproduces sexually  

  • Polyp : sessile larval stage that reproduces asexually; by budding



      













  • Body plan of a polyp/medusa : it has single opening leading to gastrovascular cavity which function as mouth (site of digestion) and anus (waste discharge)



 

  • -Surrounding the opening is a series of tentacles
  • -Tentacles have specialized stinging cells called cnidocytes/cnidoblast/nematocytes/nematoblast  -Function : capture of prey and defense









 
Cnidocytes
 
 

                                            
3 Classes of Coelenterata : 


1. Class Hydrozoa (hydra, Obelia sp.) 



  • live in fresh water
  • polyps only
  • cnidocytes in its tentacles
  • reproduction: 
      - asexual - budding 
       - sexual – takes place during fall or when water is   stagnant. 
 

 



 2. Class Scyphozoa (jellyfish, Aurelia sp.)







3. Class Anthozoa (sea anemone, Actinia sp.)








Life cycle of Obelia sp.









 
WELCOME TO KINGDOM ANIMALIA !!!



 

UNIQUE CHARACTERISTICS

  • Multicellular eukaryote                                                                 
  • Heterotroph
  • Holozoic
  • Motile at some time during life cycle
  • Mostly have nervous and muscle system
  • Diverse body plan
  • Diploid organisms
  • Mostly reproduce sexually
 

9 PHYLA OF KINGDOM ANIMALIA

  1. Phylum Porifera
  2. Phylum Cnidaria
  3. Phylum Platyhelminthes
  4. Phylum Nematoda
  5. Phylum Annelida
  6. Phylum Arthropoda
  7. Phylum Mollusca
  8. Phylum Echinodermata
  9. Phylum Chordata

 

1. PHYLUM PORIFERA

 

Leucosolenia sp.  

-Porifera in Latin means "pore bearing"
-Parazoa : Animals that lacking true tissues
-The most primitive multicellular animals
-Among the most abundant animals in the deep ocean

-Sponges are aquatic animal, mainly marine, size ranging from 1-200cm in height
-Lack nerves or muscles
-Mostly are asymmetrical
 


  • Reproduce sexually & asexually

  • Sexual reproduction: Hermaphroditic (it can produce both eggs & sperm)

  • Asexual reproduction: Budding and fragmentation



Sessile filter feeders ????

 




  • Sponges are water filtering system
  • Water contain food particles enter through pores called ostia , then through spongocoel and finally exits through large opening called osculum.
That's why they are called FILTER FEEDERS !!!!!

 
 
 
UNIQUE CHARACTERISTICS



 

 
                                                                              Amoebocytes
    
  •  Wandering the mesohyl
  • Take up food from the water and from the 
    choanocytes digest the food carry the nutrient
     to other cells.



Porocytes 
  • forming the pores/canals/ostium


 
 



 

Angiosperms

ANGIOSPERMS


Classification of Angiosperms into 2 classes:

i. Class Dicotyledonae     (Mangifera indica)  


ii. Class Monocotyledonae       (Zea mays)  





UNIQUE CHARACTERISTICS

  • Have flowers as reproductive organ
  • Seed is enclosed within ovary
  • Have complex vascular tissues  
  • Xylem consists of tracheids & vessels 
  • Phloem consists of sieve tubes  &   companion cells
  • Sporophyte is dominant
  • Double fertilization occurs producing the nutritive triploid endosperm
  • Fruits are formed which serves as protection and means of dispersal for the seeds
  • Angiosperms divided into 2 classes :
            -  Dicotyledonae
            -  Monocotyledonae