Contractile vacuole - protozoans, Biology

Assignment Help:

Contractile vacuole - Protozoans

The contractile vacuoles may differ in complexity in various groups of protozoans. In amoebae the vacuoles are carried around in the cytoplasm. 'Small vesicles join them emptying their contents into the vacuoles till the vacuole joins the membrane emptying its content to the outside.

In ciliates (e.g. Paramecium) the contractile vacuoles have a more complex structure. The contractile vacuole is located in a fixed position with an excretory pore leading to the outside surrounded by ampullae of feeder canals. The feeder canals are surrounded by a network of fine canals (20nm) in diameter, which are also connected to the tubular system of endoplasmic reticulum. The ampullae are surrounded by a bundle of fibrils that may have a role in contraction of the ampullae. The ampullae contract thereby, filling the vacuole and when the contents of the vacuole are discharged to the exterior the ampulae get disconnected so that back flow is prevented.

2370_Contractile vacuole - Protozoans.png

Figure: The contractile vacuole of Amoeba proteus is surrounded by tiny vesicles that fill with fluid, which is then, emptied into the vacuole. Note the numerous mitochondria that are believed to provide energy needed to adjust' the salt - content of the tiny vesicles.


Related Discussions:- Contractile vacuole - protozoans

What vector force does particle b then exert on a, A charged particle A exe...

A charged particle A exerts a force of 2.39uN to the right on charged particle B when the particles are 12.3 mm apart. Particle B moves straight away from A to make the distance be

How does the structure of a chloroplast enable, How does the structure of a...

How does the structure of a chloroplast enable it to build up a concentration gradient of protons?  Chloroplasts have an inner membrane system having of thylakoids. The pumpin

Stress testing after myocardial infraction, Q. Stress Testing after Myocard...

Q. Stress Testing after Myocardial Infraction? Many post infarction deaths are sudden and occur with in the first 6 months after infarction. Exercise testing from 10 days to we

Developmental biology, pioneers of developmental biology and their contribu...

pioneers of developmental biology and their contribution

Why pregnancy and lactation are critical stages in lifecycle, Why Pregnancy...

Why Pregnancy and lactation are critical stages in lifecycle? You must be aware that the situation of women is far from optimal and it is necessary to give attention to their n

Explain three basic sexual life cycles studied in biology, What are the thr...

What are the three basic sexual life cycles studied in Biology? Which of them corresponds to metagenesis? Which of them is the human life cycle? Sexual reproduction may take pl

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

Regulation of alkalinity and acidity of the plasma, Q. In which nephron por...

Q. In which nephron portion does the regulation of alkalinity and acidity of the plasma occur? The regulation of the acid-basic equilibrium of the body is done by the kidneys a

What is suppuration, Suppuration High number of PMN cells have been det...

Suppuration High number of PMN cells have been detected around implants that are associated with severe signs of mucosal inflammation. Several studies have shown the presence o

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