Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
Origin and Evolution of Metazoa
Most of the early metazoans were soft bodied and so their fossils are rare. The extremely fragmented fossil record does not shed any specific light on their origin. Therefore, 'most of the explanations on their origin are based on their embryology and -comparative morphology. A series of theories have been put forward to explain the origin of multicellular metazoans from unicellular organisms. Of these, three principal theories could be considered.
1) Syncytial Theory: That the ancestral metazoans have arisen from a multinucleate. ciliate by compartmentalization or cellularization.
2) Colonial Theory: That the ancestral metazoans have arisen from colonial flagellates by cellular specialisation and interdependency.
3) Polyphyletic Theory: That the metazoans have arisen from more than one group of organisms.
Kingdom Animalia Multicellular, heterotrophic, eukaryotes, tissues are specialised and most of them have organs, mostly highly responsive. Only gametes are haploid, fertilisation
What are histogenesis and organogenesis? Histogenesis is the procedure of tissue formation in the embryonic development. Organogenesis is the process of organ formation. Before
how to make a membrane protein which in ER transfer to PM. whether can cut some amino of sequence which play as signal guide the protein to where could the problem
Q. Are all pneumonias caused by bacteria? The Pneumonia is the generic name of inflammation of the lungs. Moreover bacterial pneumonias, there are pneumonias caused by fungi, v
Through Nuclear transfer how Dolly came into the picture. Show schematically and give all data.
What is Defective Colour Vision Defective colour vision is often called colour blindness. The ability to appreciate one or more of the primary colours is lacking. This can be e
Zooflagellates – Protozoan Zooflagellates are heterotrophs that are free living, commensals or symbiotic or parasitic in other animals. A number of species eg. Trichonynzpha a
Extracted chlorophyll pigments If we take chlorophyll molecule in a test tube and provide 2 CO and water and expose the mixture to sunlight, glucose is not formed. If we
2. Mr Konarski, 73 years old, lives in a high-level care facility. He has dementia of the Alzheimer''s type, osteoarthritis in both knees and ankles, and hypertension, which is con
Explain the Precautions for Detection of Number of Bacteria in Milk? 1. Make a thin film of milk on the slide. 2. Do not over stain with methylene blue. If over staining ha
Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd