Evolutionary Biology
Animal Body- Levels of Structural Organization (General Concepts of Zoology)
Q: What is body organization?
Ans: This is about:
how many cells are present in an animal body? Single and multicellular animals
Whether the nucleus is present or absent? Prokaryotes and eukaryotes.
How many different types of multicellular animals are living on the earth? Colonial (Porifera) and individual animals (Coelenterata to Chordata).
Do the individual animals have the same tissues and organ development? No. Tissue level and Organ level organization.
How many embryonic germ layers are present in the embryo after gastrulation? Two- Diploblastic (Coelenterates), Three- Triploblastic (Platyheminthes to Chordates).
Is the gut formation of embryonic development is same in all multi-cellular animals? No. Protostomes (Annelida, Arthropods & Mollusca), deuterostomes (Echinodermata, hemi-Chordata and Chprdatea).
Where are the internal organs located in multicellular animals? Coelomic fluid in the Coelom
Do all multicellular animals have the same coelom development? No. There are 3 types: Acoelomata, Pseudocoelomata and Enterocoelomata.
Do the organs arrange mathematically (Geometrically) in all the animal’s body? Not yet. Amoeba (Protozoa) and sponges (Porifera) have no regular shape (irregular), but, Cnidarians possess Radial and Bi-radial symmetry, Bilateral symmetry is present in Platyheminthes, Nemathelminthes, Annelida, Arthropods & Mollusca, Hemi-Chordata and Chordates. The Echinoderms are special adults with Penta-Radial, but larvae have bilateral symmetry.
Video-Over view of …above
# All the animals do not have the same body structure or organization. WHY?
@ Because all the animals are not living in the same ecosystem!
# What is the relationship between the environment (Ecosystem) and animals?
@ Animals adapt and shape and organize their body structure according to the influence of Physico-Chemical and Biological factors.
Physical factors- Light, temperature, humidity, atmospheric pressure etc.
Chemical factors- Oxygen, Co2, Nitrogen, Minerals and pH of water etc.
Biological factors- symbiosis, mutualism, parasitism, predation and competition etc.
Video- Ecosystem-animal, factors, adaptations …