Cilia and flagella, Biology

Assignment Help:

CILIA AND FLAGELLA

  • Purkinje first observed ciliary movement.
  • Hodge studied detail structure of sperm flagellum.
  • Manton studied structure of cilia in plants.
  • Cilia and flagella are simillar in structure. There are some external differences between cilia and flagella.

Cilia

Flagella

Shorter - 5 to 1 0 m in length

 

More in number on a cell

(14000/cell)

 

Exhibit sweeping or pendular movement.

It includes power stroke and recovery stroke.

Action co-ordinated

upto 150 m long

 

Few in number

(1-8/cell)

 

undulating movement

 

Action not co-ordinated

  • Both structures help in locomotion, excretion, secretion and transportation.
  • Cilia and flagella are present in eukaryotic cells except slime moules.
  • Cilia and flagella are also present in prokaryotic cells except Anabena (BGA).
  • Cilia and flagella shows 9+2 arrangement of microtubules.
  • Cilia and flagella consists of 3 parts -

(1) Basal body                 (2) Basal Plate               (3) Shaft

(1) Basal body

  • It is also known as kinetosome or basal granule or blepheroplast.
  • It has 9+0 orientation of microtubule.
  • Hub protein present in the proximal part of basal body but absent in distal part.
  • Central part of basal granule is composed of semisolid cytoplasm called "Central Hub". Microtubules connected to central Hub with the help of protein fibres called primary fibres. Secondary fibres connect microtubules with each other. The triplet microtubules form an angle of 40° with the tangent of basal granule.
  • Rootlet - A conical bundle of protein fibers arise from basal body, Rootlet have dark bands composed of ATPase.
  • Synthesis of ATP takes place in dark bands.

(2) Basal Plate

  • Present between basal body and shaft.
  • It conects basal body and shaft to each other.
  • Two major changes occur at the region of basal plate -

(i) Triplet of peripheral microtubule convert into doublet of microtubules. (ii) Central microtubules develop from distal end of Hub protein.

(3) Shaft

Shaft consists of two parts -

(i) Sheath

(ii)  Axoneme

  • Outer covering of cilium or flagellum is called sheath. Peripheral sheath covers peripheral microtubule whereas central sheet covers central microtubules.
  • Axoneme of shaft consists of 11 microtubules (9 peripheral and 2 central).

738_cilia and flagella.png

  • Axoneme shows 9+2 arrangement of microtubules.
  • Each peripheral microtubule consists of A and B subtubule.
  • A subtuble has two bent arms, these are made up of dyenine proteins. These arms directed in clockwise fashion. Arms of A-tubules composed of an enzymatic protein. Dynien similar to myosin of muscles. Dynien protein have ability to split A TP ( in presence of Ca+ 2 and Mg+2) and liberate energy for movement. Cilia and flagella bend or move due to sliding of microtubules along one another while maintaining their individual length (mechanism simillar to muscle contraction).
  • Each peripheral microtubules consists of tubulin protein. Tubulin simillar to Actin protein of muscles.
  • A and B subtubules connected to each other with the help of Nexine protein.
  • Both central microtubules connected to each other with protoplasmic bridge. Central sheath is present around the central microtubule.
  • Each A subtubule liked to central sheath with the help of radial spoke. Terminal end of radial spoke forms knob like structure that is known as spoke head. Spoke head is present near to central sheath.
  • Transition junctions are also present between central sheath and spoke head.
  • Shaft of cilium of flagellum filled with proteinacious matrix.

Related Discussions:- Cilia and flagella

Define some example of acidic and basic buffer, Define Some Example of Acid...

Define Some Example of Acidic and Basic Buffer? Frequently used example of acidic and basic buffer includes: - Acidic buffer: a mixture of CH 3 COOH (acetic acid) + CH 3 C

Define reagents for measurement of ph, Define Reagents for Measurement of p...

Define Reagents for Measurement of pH? Buffer solutions of pH 4, pH 7 and pH 9.18 for calibration and an unknown solution (i.e. solution of unknown pH) You can prepare these

What is a bio regenerative system, What is a bio regenerative system? Why i...

What is a bio regenerative system? Why is it essential? Nutritional requirements for long flights have been refined, placing more demands on food development. Despite the techn

What is the dental implants option, Dental implants option It is import...

Dental implants option It is important that the type of prosthetic options selected for the patient is not only cost effective, but also must  be predictable and restores the e

Osmotic and ionic regulation, Osmotic and Ionic Regulation The  ammono...

Osmotic and Ionic Regulation The  ammonotelism, ureotelism and uricotelism are the adaptations of the animals for the removal of toxic nitrogenous wastes and thereby maintain

Human impact on enviroment, What are the principal sources of of excessive ...

What are the principal sources of of excessive nitrate and phosphatebin rivers and lakes?

Nematodes, how nematodes adapt to their mode of feeding

how nematodes adapt to their mode of feeding

Describe congenital pulmonary stenosis, Describe Congenital Pulmonary Steno...

Describe Congenital Pulmonary Stenosis? The murmur present since birth. PS may be valvular, sub-valvular, or supravalvular. An obstruction may occur within the RV cavity by an

How to measure post repair prv/iv pressure, How to measure Post Repair Prv/...

How to measure Post Repair Prv/iv Pressure ? In the operating room, after coining of1 bypass and before removing cannulae the RV and LV pressures are measured. The pressures ar

Discuss about xeno-transplanation, Discuss about xeno-transplanation Mo...

Discuss about xeno-transplanation Most defects / diseases treated by xeno-transplanation are not genetic in origin so the therapy will have no impact on gene pool in terms of c

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