In lower animals ex creation occurs by from the body surface
Answers
Various organisms show diverse form of excretory systems based on the complexity of their body organisation.
We can broadly classify Kingdom Animalia into the following categories:
1. Protists( includes amoeba )
2. Porifera (Sea sponges)
3. Coelenterata ( includes jelly fishes)
4. Ctenophora (colourful jelly fishes)
5. Platyhelminthes(flatworms)
6. Aschelminthes(roundworms)
7. Annelids(Earthworm)
8. Arthropoda(Insects)
9. Molluscs(Octopus)
10. Echinoderms(Starfishes)
11. Hemichordata(Balanoglossus)
12. Chordata( includes fishes, amphibians, reptiles, birds and mammals)
Out of these 12 phylum's, In chordata
there are certain specific excretory materials present according to level of affinity of that particular organism with water. They are:
1. Ammonotelic(fishes, amphibians)
2. Ureotelic(mammals)
3. Uricotelic(Birds, insects)
The exact evolutionary excretory modes are as follows for all 12 phyla:
1. Potista: Cell membrane(exocytosis)
2. Porifera: through pores(osculum)
3. Coelenterata: body surface
4. Ctenophora: body surface
5. Platyhelminthes: flame cells/solenocytes
6. Aschelminthes: protonephridia
7. Annelids: nephridia
8. Arthropoda: Malphigian tubules(most common)
9. Molluscs: metanephridia(organ of bojanus)
10. Echinoderms: Body surface
11. Hemichordata: single glomerulus(Part of nephron which is the structural and functional unit of kidneys)
12. Chordata: ( includes fishes, amphibians, reptiles, birds and mammals)