Sensory Syatem In Invertebrates Essay

8105 words - 33 pages

Introduction: vertebrates are distinguished from other groups of animals by certain characteristics, principally related to their spinal cords and nervous systems, namely, the presence of a dorsal notochord surrounded by mesodermal tissue, which gives rise to a vertebral column in adults of most species, and a tubular nervous system lying dorsal to the cord, concentrated in the midline, and very well developed at its cephalic end (cephalization). The extent and pathways of nervous system development differs between invertebrates and vertebrates, even though, in all animals that have a nervous system, it is derived predominantly from ectodermComparative embryology and anatomy have ...view middle of the document...

Segmentation (metamerization) appears. The central nervous system is ventral (bilateral ventral cords), has no cavity and localization of sensory cells seems to be responsible for the segmental concentration which forms the metameric gangliaTHE SUPERIOR AND ADULT ANNELIDS (nereis, Lumbricus): the central nervous system is still ventral (single cord and ganglia) without a cavity, and there is transverse concentration. The cerebral ganglia are specialized for vision and olfactionTHE HEMICHORDATES (enteropneusts): a dorsal tubular and a solid ventral nervous system. There is no cord, but there is a cephalodorsal diverticulum of the intestine corresponding to a dorsal nervous tube. The diverticulum is incompletely separated from the overlying ectoderm from which it is derivedTHE PROCHORDATES (Chephalochordata, Amphioxus): a dorsal cord and a dorsal tubular central nervous system entirely developed from dorsal ectoderm. A ventral system is no longer seen. The anterior vesicle represents a true rudimentary brainVertebrate nervous system (Chordata): mesoderm determines the development of the nervous system and sense organs. The appearance of mesoderm groups together the inductive capabilities and marks an important stage in the genesis of developmentTHE NERVOUS SYSTEM is relatively independent of the sensory organization. However, the eye and general sensory receptors, are directly derived from the nervous systemDuring evolution, relationships between the nervous system and the sense organs are modifie In invertebrates, the nervous system appears to be only an accessory structure to the sensory system. In vertebrates, the importance of the nervous system becomes so great that everything else is organized for it and around itIN VERTEBRATES SUCH AS FISH, the 5 neural vesicles presage the cephalization of the higher vertebrates. During the slow progression of evolution, the role of the prochordal plate becomes essential since, in humans, it induces brain formationAnimals respond to the messages they receive from the world aound them. Their reactions to the outside world depend on how the data collected from their surroundings are correctly coded into signals that can be received and processed by neurons in the brain. The sensory organs provide the only means of communication from the environment to the nervous system. Sensations arise when signals are detected by sensory receptor cells are transmitted through the nervous system to the designated part of the brain. Various organs and cells are designated to receive specific stimuli. The major categories of sensory reception addressed here are chemoreception, mechanoreception, and photoreception. What are the general properties of sensory reception and how are these messages transmitted to the central nervous system?Animals require a constant detection of information from their surroundings. Such information is the animal's link to the outside world. Sensory input is initially detected by sensory receptors....

Other Essays On Sensory Syatem In Invertebrates

American Dream Essay

765 words - 4 pages The American Dream is the quintessence of a comfortable victorious life, which often includes material prosperity, a house, an improved life for one's kids, and sometimes; it means achieving any goals one may have regardless of what class he or she comes from (O'Connor, Sabato and, Yanus 19). In recent years, it has become more difficult to achieve the American Dream; this is mainly due various issues involving the relationship between the

adadwq sdadasd Essay

504 words - 3 pages Dengan Smarty Ring, Anda bisa membaca notifikasi di handphone Anda melalui jariKetika semua orang membicarakan kecanggihan Google Glass atau smartwatch, tak banyak orang yang berpikir bahwa sesuatu yang ukurannya lebih kecil dari itu juga bisa berguna. Ide itulah yang diusung Smarty Ring, yang memperlihatkan semua notifikasi handphone Anda sehingga Anda tidak harus mengangkat handphone Anda untuk mengetahui apa yang terjadi. Smarty Ring, yang

commerce

519 words - 3 pages Related text: American History X Comment by George Moulos: You can't analyze a film the same as a book.If you re doing film you have to do film techniques, not literary techniques.-Derek Vinyard after going to prison and learning that his prejudice stemmed from ignorance he teaches his brothers Danny vineyard that his fascism and racism was wrong and ignorant.Movie Summary:Derek Vineyard begins in the movie as a troubled young man who due to his

Miniscribe Corporation

1685 words - 7 pages EXECUTIVE SUMMARYTerry Johnson, a native of Longmont, Colorado established the MiniScribe Corporation, a disk drive manufacturing company that would grow to be one of the largest producers and distributors of disk drives for personal computers in America.This report focuses on relevant facts and figures in the evaluation of MiniScribe's liquidity, profitability, and overall stability aiming to determine whether or not maintaining its stocks on

dream world

384 words - 2 pages asleep mere seconds ago and as I groggily looked around something did not seem right. The room looked the same as it did before I went to sleep. In the bright orange light that seemed to come from hells keep itself, shown through the flimsy curtains from the eerily noiseless street behind our house I could see that nothing was amiss. Nothing that I could notice straight away that is.As I got up from my bed, I saw that my sister was not in her

the adverb clause.ppt

754 words - 4 pages USE OF ARTICLES (a, an, the)What did these words originally mean?A/AN is an old word meaning `one'(in many European languages the ordinary word for `one' is used to translate English `a' or `an' and you can also sometimes use Cantonese `yat go' in the same way)THE is an old word meaning `this' or `that'These words no longer have their full original meaning but if you remember that meaning it can sometimes help you to decide which word you need

Highfyr

537 words - 3 pages Breanna PonceMia Sandoval Dominick KlingbyllAugust 26, 2013Block 2The Effect of Pineapple on Jell-OBACKGROUND:Protein was a big part of this gelatin lab. Protein is a multipurpose macro molecule. Gelatin is a protein made out of Jell-O, we used Jell-O in our lab. The students had to put pineapple in the gelatin to see if it will form. The enzymes in the pineapple prevented that from happening. Enzymes are a biological catalyst. Bromelain is the

merits and demerits of mordern gadgets

418 words - 2 pages all gadgets are operated with it be it AC, TV, computer, a telephone, or any other modern appliance. Perhaps there were times when every work was done with hands be it grinding or travelling far off places. People were tough who could walk for miles and work ceaselessly. In modern times we can't ascend the stairs without feeling a burden over our stamina. Modern gadgets have completely transformed the human life and health to a great extent. The

Case Study Dr Harold Wolf

614 words - 3 pages COMPREHENSIVE PROBLEMDr. Harold Wolf of Medical Research Corporation (MRC) was thrilled with the response he had received from drug companies for his latest discovery, a unique electronic stimulator that reduces the pain from arthritis. The process had yet to pass rigorous Federal Drug Administration (FDA) testing and was still in the early stages of development, but the interest was intense. He received the three offers described below this

Personal Explorations Paper

957 words - 4 pages that I was not. Things such as my expression of sexuality, different levels and aspects of my psychology, my personal reactions to certain social situations, and the way I pursue and value my career were all evaluated by answering questionnaires. In the end a lot was revealed about the way I handle and look at things and even my overall personality.My expression of sexuality was not really a huge surprise to me. My values and my religious

Pooooooped

2015 words - 9 pages The Open-Field System .Three field rotations helped keep fields fertile traditional village rights reinforced traditional patterns of farming.Peasants were exploited in a number of ways, with those in Eastern Europe generally the worst off.The Agricultural RevolutionThe use of more complex systems of crop rotation increased the amount of land under cultivation.Grain crops were alternated with nitrogen-storing crops.The open-field system was

Similar Papers

Crayfish, The A Complete Classification, Habitat, Predator And Prey, Body Plan, Nervous System, Circulatory System, Digestive System, And Respiratory System

654 words - 3 pages been reported to be preyed upon by at least 46 species of fish, 10 amphibians, 20 reptiles, 38 birds, and 6 mammals (including humans). Crayfish are preyed upon heavily by fish, such as trout, pickerel, and bass, and other invertebrates may eat them.Body PlanCrayfish have bodies similar to that of the presumed ancestral crustacean. Such a body is essentially shrimp-like in that it is elongate and nearly cylindrical in cross section. The abdomen is

Polymer Mechanichemistry Essay

265 words - 2 pages rubber. With this testing, elastomers underwent a series of compressions, increasing the number of compressions each time, thinning out elastomer to paper thin in the hopes that it would reform to its original shape. Throughout the whole experimental process, the team discovered that the elastomers bounced back to its original shape with only cosmetic damages. From here, they applied this knowledge to the world. Testing with rubber polymers, the students has discovered that once the rubber has been compressed in shoes, the polymers stop supporting the joints. This signals that the shows are worn out.

The Changing Essay

288 words - 2 pages One hand Reaches out And pulls a lost soul from harm While a thousand more go unspoken for They say what good have you done By saving just this one It's like whispering a prayer In the fury of a storm And I hear them saying you'll never change things And no matter what you do it's still the same thing But it's not the world that I am changing I do this so this world will know That it will not change me This heart Still believes The love and

The Importance Of The Act Of Reading” By Paulo Freire Essay

1423 words - 6 pages 4BredahlHarlie Cheyenne BredahlProfessor Peter EppsComposition II08 September 2014I"The Importance of the Act of Reading" by Paulo Freire, describes the importance of the act of reading beyond numerous experiences in his life as a child, a teenager, and an adult. Freire begins his article by taking readers back to where he was born, in his home city Recife, Brazil. He uses very itemized imagery to describe the trees, the house and the atmosphere