Foot as burrowing organ, Biology

Assignment Help:

Foot as Burrowing Organ

The Scaphopoda that usually have burrowing habit, possess foot suitably modified for burrowing purpose. The conical and protrusible foot of Dentalium is trilobed at its distal end. It can be thrust into the sand while burrowing occurs. A lobe encircling the cone can be erected to increase its anchorage. In between burrowing bivalves, in some like Pholas which bores into rock the blunt, short foot is employed for boring. They attach by the sucker-like surface of the foot; the muscles of the foot produce several movements producing the requisite cutting force; the anterior ends of the valves give the sharp cutting edge. The shipworm Teredo bores into wood using more or less similar mechanism. In Yoldia, the two sides of the foot can be folded to make a wedge shape for easy burrowing into the sand or mud. In some burrowing gastropods, for example Sigaretus , the anterior part of the foot, called protopodium, is as well specialized to become wedge like. The burrowing action in molluscs is typically accomplished through thrusting the blade of the foot into the sand or mud. The distal part of the foot is dilated along with the aid of protractor muscles and when this is accompanied by blood pressure it acts like an anchor. Contraction of the retractor muscles now pulls the animal downward.


Related Discussions:- Foot as burrowing organ

The z-gene codes for permease, Select the two correct statements out of the...

Select the two correct statements out of the four (a - d) given below about lac operon. 1. Glucose or galactose may bind with the repressor and inactivate it 2. In the absenc

Invertebrete zoology, give an example invertebrate phylum/phyla for protopl...

give an example invertebrate phylum/phyla for protoplasmic grade organization

What are protozoans? explain their functions, Protozoans are microscopic in...

Protozoans are microscopic in size however some are large enough to be seen with naked eye. Microscopic organisms such as these have numerous advantages, one of which is that they

Abscission - effects of plant growth regulators, Abscission - Effects of Pl...

Abscission - Effects of Plant Growth Regulators Abscission of leaves and fruit is one of the more obvious characteristics of senescence. Leaves do not fall simply because they

Formation of identical twins and fraternal twins, Describe the events whic...

Describe the events which lead to the formation of (a) identical twins, (b) fraternal twins.   (a) Identical twins are derived from the products of a one zygote which separa

Which type of gamete produced by a heterozygous individual, Which is the ty...

Which is the type of gamete produced by a heterozygous individual? What is the genotypical proportion of these gametes? Heterozygous individuals, for instance, AA, produce two

Identical chromatids or separation of homologous chromosomes, Q. During mit...

Q. During mitotic anaphase is there separation of identical chromatids or separation of homologous chromosomes? In the anaphase of mitosis the identical chromatids complete and

Can it be influenced by environmental factors, Variation exhibited in share...

Variation exhibited in shared traits present in a population is due to alleles of the shared genes. can be influenced by interactions of alleles of multiple genes. Can be influence

Name the ceramics used in bioactive, Bioactive Ceramics:-   Hydroxyapa...

Bioactive Ceramics:-   Hydroxyapatite, Tricalcium phosphate, Tetracalcium phosphate, calcium pyrophosphate. Fluorapatite, brushite,  bioglass.

What are the main events of the final mitotic period, What are the main eve...

What are the main events of the final mitotic period? The final mitotic phase is telophase. In telophase the following events happens: decondensation of chromosomes, every set

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