--%>
Assignment Help - homework help

Procedure of evolutionary cephalization

Using the examples of the invertebrate nervous systems how can the procedure of evolutionary cephalization be explained?

E

Expert

Verified

Considering the example of the invertebrates it is observed that evolution creates the increasing of complexity of organisms to be accompanied by the convergence of nervous cells to special structures for commanding and controlling: ganglia and brain. In simple invertebrates, such as cnidarians, the nervous cells are not concentrated however they are found dispersed in body. In platyhelminthes a beginning of cephalization with anterior ganglion concentrating neurons is already verified. In annelids and arthropods existence of a cerebral ganglion is evident. In cephalopod molluscs the cephalization is even greater and brain commands the nervous system.

   Related Questions in Biology

  • Q : Setting up a new business Setting up a

    Setting up a new business and making it click particularly in anew field of activity is a challenging job. Setting up a unit for supplying of packed lunch boxes is one such business. Success in the same depends on the ability to sell the concept in an

    		•
  • Q : Define the term Negotiations

    Negotiations: Business negotiation is the process by that classically two or more parties come together to try to make an equally agreeable contractual decision. All parties will have competing interests and, hence, negotiations can be rather lengthy

    		•
  • Q : Definition of Communication -

    Communication is a nature instinct of all living creatures. It is the basic need of all human beings. It plays all the more significant role in the present day organizations which are complex, dynamic and socially oriented. Effective communication keeps the organization vibrant, vital and smooth

    		•
  • Q : Separation of stomach from oesophagus

    Which valve separates stomach from the oesophagus? Specify its function?

    		•
  • Q : What happen when pepsin passes into

    As pepsin is a gastric enzyme does it contain an acid or basic optimum pH? What occurs to pepsin whenever it passes into duodenum?

    		•
  • Q : Feature of DNA molecule is its

    One characteristic feature of DNA molecule is its replication ability. Write down the consequences of failures throughout DNA replication?

    		•
  • Q : Signaling arrays and responses What are

    What are the similarities and differences  between the  signaling arrays and responses that are driven and associated with the "Jasmontates" in plants, and the "eicosanoids"; arachidonic acid cascade components in animals?  This is a large enough questi

    		•
  • Q : Gastrulation What is meant by the

    What is meant by the gastrulation? How during gastrulation first two germ layers are formed? Specify these germ layers?

    		•
  • Q : What do you mean by immunoglobulin-D

    What do you mean by immunoglobulin D?

    		•
  • Q : What is tuberculosis What is

    What is tuberculosis? What are their symptoms.

    		•