Biology: Chordate and Pharyngeal Gill Slits Essay

Submitted By paininthebutt
Words: 853
Pages: 4
Open Document
BIOLOGY LAB: CHAPTER 40 OUTLINE

Protostomes (annelids, mollusks, and anthropods)
Deuterostomes
Deuterostomes vs. Protostomes
The blastopore (opening cavity formed in a developing embryo) gives rise to an anus rather than a mouth

PHYLUM ECHINODERMATA
Echinoderms
Echino= spiny; derm=skin
Ossicles-internal skeleton of calcerous plates
They have 5 classes distinguished by the arrangement of their ossicles
Adult echinoderm-radially symmetrical and pentaradial
Larvae echinoderm-bilaterally symmetrical
Water vascular system-series of coelemic water-filled canals
Tube feet (ending)

CLASS ASTEROIDEA
Common sea star Asterias mouth is at the center of the lower oral surface, and the anus is on the upper, aboral surface dermal gills-surrounds the blunt spines used for respirations by diffusion pedicellariae-used to remove debris from the surface madreporite-sieve connecting the water vascular system with the environment (aboral surface)

CLASS OPHIUROIDEA
Brittle stars
Ossicles are typically thick and have attached musculature shield “brittle” their arms detach easily, allowing them to escape from their predators faster
Ambulacral grooves-closed
Tube feet are NOT used for locomotion

CLASS CRINODEA
Sea lilies and feather stars
Most ancient echinoderms
Their oral surface faces up
Ossicles- are well developed and give them a fine coarse appearance
Filter feed to eat; mucus on their tube feet

CLASS ECHINOIDEA
Sea urchins and sand dollars
Lack distinct arms
Ossicles-test
Allow long tube feet to protrude
Spines-longer, jointed and movable than those of other classes
Locomotion
Aristotle’s Lantern-internal structure of five teeth

CLASS HOLTHUROIDEA
Sea cucumbers
Tentacles-modified tube feet
Soft bodies with reduced ossicles and few if any in spines
Body axis is horizontal; less radial symmetry
Cephalization
The tentacles secrete a mucus that captures small floating organisms, which they eat
Evisceration
Rupturing anteriorly and rapidly expelling their pharynx, digestive tract, and other organs

PHYLUM CHORDATA
Characterized
Dorsal hollow nerve cord
Notochord-a cartilaginous rod that forms on the dorsal side of the gut in the embryo
Pharyngeal slits-openings in the throat that filter water that has entered through the mouth
Postanal tail
Bony skeleton

SUBPHYLUM UROCHORDATA
Tunicates/ sea squirts
Sessile/planktonic marine organisms whose larvae possess the general chordate form
Adult-is highly modified to include a sievelike basket perforated with pharyngeal gill slits surrounded by a cellulose sac called a tunic
A larval turnicate has bilateral symmetry, a dorsal nerve cord, a notochord, and a postanal tail BUT LOSSES these features when it settles for adult life

SUBPHYLUM CEPHALOCHORDEA
Lancelets
Small, fishlike, marine chordates that burrow in sand and mud
Branchiostoma
The dorsal nerve cord and notochord extend the length of the animal. The buccal cavity surrounds the mouth followed by a long pharynx with many gill slits (openings) separated by gill arches of reinforced tissue
The anus is not terminal
After water passes by the gill arches it moves into a surrounding chamber called an atrium and then leaves the body through the atriopore

SUBPHYLUM VERTEBRATA
Fish, birds, amphibians, reptiles and mammals
Have a vertebral column that replaces the notochord
Distinct head
3 classes

CLASS AGNATHA
Ammocoete-larva of a lamprey
They lack jaws but have a cartilaginous endoskeleton and a notochord
7 pharyngeal gill slits are near the head
The mouth is at the center of the round buccal funnel and is armed with horny teeth and a rasping tongue

CLASS CHONDRICHTHYES
Sharks, skates, and rays
Endoskeletons is cartilaginous and the anterior gill
Show More

Related Documents: Biology: Chordate and Pharyngeal Gill Slits Essay

chordates and vertebrates lab Essay

Chordates and Vertebrates Lab Introduction/Background: In this lab students are learning all about chordates and vertebrates and will be viewing examples of them as well. The examples to be viewed in the lab are Tunicates, Lancelets, Lampreys, Rays, a Dogfish shark, a Perch, Catfish, Eels, Toads, Frogs, Lizards, Snakes, Roadrunner (foot), Barn owl (wing), Cotton tail rabbit , and an Opossum. The different types of chordates/vertebrates discussed in this lab are the urochordata, cephalochordate,…

Words 2276 - Pages 10

Essay on bio lab 20

lab 1201 19th of April 2014 Report About Vertebrates Three Classes Aves, Reptilia and Mammalia Chordates are animals with backbones, and it is known that animals with backbones are not only the most complex and complicated groups of animals, but also really highly devolved. They also have interior skeletons and have bilateral symmetry. They have more advanced brains. Organism that belongs to phylum Chordates have to have four features, which include a notochord, there is a semi-flexible rod which not…

Words 1585 - Pages 7

Essay on Biology Review Notes

Bio94 (TA Alejandra Rodriguez) Study guide for the final exam on Wednesday March 20, 2013 Hi! This is only a skeleton study guide that you may use to help organize the key concepts presented in lectures. Some important points are in bold. I also added the figures of each chapter that I consider useful for studying (it doesn’t mean that you have to memorize them! Just try to extract the useful information). I also added the homework questions with some hints. I wrote all my comments in blue…

Words 6970 - Pages 28

anat terms Essay

Research Writing Research Process Organization Citing References Writing Process View All Research Writing Articles The Anatomy of a Research Paper A research paper encompasses many things. It may be a paper due at the end of a term or class. It may be the result of weeks, months or years of research. During the course of completing this type of academic writing assignment, you examine an issue to write an analytical or argumentative paper that is a summary of research and your conclusions…

Words 8587 - Pages 35