What is class polychetae - marine worms, Biology

Assignment Help:

What is Class Polychetae - Marine Worms?

The polychaetes differ from the oligochaetes in several ways. The name itself suggests one of the differences. The prefix "poly" means "many," as opposed to "oligo," meaning "few." Thus, the polychaetes have many hair-like bristles. They also have paired appendages called parapodia that bear the numerous setae. Parapodia have several functions, including helping the worms swim or crawl, as well as providing an anchoring mechanism. Parapodia, in addition, provide increased surface area for gas exchange. Most polychaetes live in marine habitats, and they can be found either living as plankton, crawling on the sea floor, or living in tubes, which the worms secrete around themselves.

Polychaetes also differ from the other two groups in that their anterior is better developed. They have a definite head region with sensory apparatus that include light-sensitive eyes.

 

 


Related Discussions:- What is class polychetae - marine worms

Explain synaptic transmission between neurons, Q. How does synaptic transmi...

Q. How does synaptic transmission between neurons take place? The propagation of the action potential along the axon reaches the region immediately anterior to the presynaptic

Describe about the term - neuropsychological assessment, Describe about the...

Describe about the term - Neuropsychological assessment Neuropsychological assessment has its roots in neurology, the branch of medicine that focuses on the nervous system and

Explain exotic species, Explain exotic species? Describe with the help ...

Explain exotic species? Describe with the help of two examples how the exotic species disturb the native species of an ecosystem ?

Intracellular sodium concentration of the motor neuron, Intracellular sodiu...

Intracellular sodium concentration of the motor neuron A complete motor neuron is removed from a frog and placed in normal physiological saline at 1 AM.  The neuron is healthy.

Why alkaline phosphatases use water as a second substrate, Alkaline Phospha...

Alkaline Phosphatases use water as a second substrate. Why do we still treat their kinetics as if they were for a single-substrate reaction?

Explain spermatocyte I and spermatocyte II, What is the difference between...

What is the difference between spermatocyte I and spermatocyte II? The spermatocyte I (2n) undergoes the primary division of meiosis (meiosis I) originating two spermatocyte II

What is etiopathology, Q. What is Etiopathology? Who is likely to devel...

Q. What is Etiopathology? Who is likely to develop gout? What are the risk factors? Let us find out. Gout is caused when there is over production of uric acid in normal purine

Cohesiveness and surface tension-properties of water, Cohesiveness and Surf...

Cohesiveness and Surface Tension Water flows freely, yet water molecules do not break apart. They cling together particularly to polar surfaces. Therefore, water can fill a tub

Describe the maturity stages in fish, Question 1: (a) Describe the mat...

Question 1: (a) Describe the maturity stages in fish. (b) "k" and "r" selection strategies are commonly used to describe the response of fish to biotic and abiotic cond

Explain about the isoflavones, Explain about the Isoflavones? These are...

Explain about the Isoflavones? These are usually treated separately from the other five subclasses and are an area of considerable research interest. Isoflavones are found almo

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

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!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd