Locomotory structures, Biology

Assignment Help:

Locomotory Structures

Annelids possess three kinds of locomotory structures, namely parapodia, setae and suckers. Parapodia are segmentally arranged, lateral, hollow extensions of the body into that also extends the coelomic cavity. Each parapodium basically consists of two lobes, a dorsal notopodium and a ventral neuropodium and every lobe bears a bundle of bristles or setae supported by an aciculum. Related with each parapodium are dorsal and ventral sets of oblique muscles, and as well the intrinsic protractor and retractor muscles. During movement, two parapodia of a segment remain in opposite phases of motion and so cause a sort of paddling activity by water. The bristles and acicula are protruded and withdrawn through the activity of the intrinsic muscles. Parapodia are the major locomotory organs of polychaetes. In accordance with the different functions which they perform, parapodia exhibit variations of form among different polychaetes.


Related Discussions:- Locomotory structures

Some common air pollutants: oxides of nitrogen, Oxides of nitrogen:   ...

Oxides of nitrogen:          These include nitrogen monoxide (NO) and nitrogen dioxide (NO2). NO is a colourless, odourless and inert gas but like CO it can also combine with

Discuss the role of dental implants in orthodontic anchorage, Q. Discuss th...

Q. Discuss the role of dental implants in orthodontic anchorage? The increasing popularity of dental implants has led to its use for orthodontic anchorage. Conventional means o

Reproductive system of asteroidea, Reproductive System of Asteroidea S...

Reproductive System of Asteroidea Sexes are separate in several asteroids. There are ten (10) gonads, two in each arm. They emerge tuft-like or as cluster of grapes. Mature go

Why the l enantionmer is more dominant, In the Miller-Urey experiment, amin...

In the Miller-Urey experiment, amino acids of bothe the L and D enantionmers. Why is it that the L enantionmer is more dominant in living things?

Sequencing of dna fragments, Q. If a fragment of nucleic acid has a nucleot...

Q. If a fragment of nucleic acid has a nucleotide sequence TAC can one assert that it is an anticodon or a codon? A nucleic acid having a TAC sequence surely is not tRNA it is

Hypolimnion - summer stratification, Hypolimnion - Summer Stratification ...

Hypolimnion - Summer Stratification This zone forms the bottom layer which is deep, cold and non- circulating. The hypolimnion is generally rich in nutrients though its oxygen

Name the implant failures, Implant failures On the basis of the stage w...

Implant failures On the basis of the stage when problems occurs implant failures can be classified as : i) Before Abutment Connection. ii) During Abutment Connection.

How many carbon dioxide molecules are liberated, How many carbon dioxide mo...

How many carbon dioxide molecules are liberated after each cycle of the Krebs cycle? For a single glucose how many carbon dioxide molecules were already liberated by the aerobic re

Stratification of vegetation - qualitative characters, Stratification of Ve...

Stratification of Vegetation - Qualitative Characters Stratification of vegetation is another important feature of plant communities. There are different vertical strata in di

What is plant transpiration, What is plant transpiration? What are the two ...

What is plant transpiration? What are the two main types of plant transpiration process? Which of them is more significant in volume? Transpiration is the loss of water from th

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