Define the functions of platelets, Science

Assignment Help:

Define the functions of platelets

The main function of platelets, or thrombocytes, is to stop the loss of blood from wounds, i.e. haemostasis. Let us learn about this function. The platelets:

i) Release a chemical substance called serotonin, that cause vasoconstriction. This ensures reduced flow of blood from the injured site,

ii) Aggregate to plug the vascular plug at site of injury, and

iii) Have like skeletal muscles, actin and myosin proteins, which contract to bring about clot retraction. This ensures normal flow of blood around the sealed injured blood vessel.

The plug formed by the platelet arrests bleeding. The time taken for the blood to cease flowing from an injured site is termed as bleeding time. The platelet plug that is formed is friable and cannot be relied to check bleeding for very long. The blood forms a fibrin meshwork of threads that forms a better plug. This may take a few minutes before such a first aid mechanism acts in the body. The time taken for a clot to form is termed as clotting time. Before a patient is taken to the operation theatre, the doctor assesses the bleeding and clotting time to prevent excessive loss of blood during time of operation. The patient whose bleeding time is less than 4 minutes and clotting time is less than 12 minutes may be taken up for surgery after the other investigations are normal. So far, we have learnt about the constituents and functions of blood - the fluid connective tissue.


Related Discussions:- Define the functions of platelets

Why did the continents spread apart, Why did the continents spread apart? ...

Why did the continents spread apart? This is because of the heat generated from the earth's interior and earthquakes - the convection currents deep within the earth due to the m

Determine the most important soil animals, Explain why earthworms are said ...

Explain why earthworms are said to be the most important soil animals. Earthworms ingest organic matter as well as soil where they mix, granulate and excrete to increase stabil

Define antidiuretic hormone - posterior pituitary, Define Antidiuretic Horm...

Define Antidiuretic Hormone - Posterior Pituitary Antidiuretic hormone or ADH, also known as vasopressin, is another polypeptide containing 9 amino acids. As the name of the ho

Albanian, what is the mendeleyev

what is the mendeleyev

Explain the regulation of blood composition, Explain the Regulation of Bloo...

Explain the Regulation of Blood Composition Each part of the nephron has different types of cells with different properties. An understanding of this is important to know how t

State the mechanical analysis of soil texture, Mechanical Analysis of soil ...

Mechanical Analysis of soil texture Mechanical analysis is actually the particle size analysis which is done to determine the amount of various separates or the groups of part

Explain cholecystokinin - movements of gall bladder, Explain Cholecystokini...

Explain Cholecystokinin - Movements of Gall Bladder Cholecystokinin: Active contraction of gall bladder during digestion is due to the hormone cholecystokinin. Acid extracts o

Ozone gas, how does it get into the earth?

how does it get into the earth?

Examining sand with a magnifying glass, Examining sand with a magnifying gl...

Examining sand with a magnifying glass Study a small amount of sand with a magnifying glass or under the low power of a microscope if there is single available. The nearly colo

In what conditions an element is called an essential element, Under what co...

Under what conditions an element is called an essential element?   An element is called as an essential element, if:   a.  The plant can not complete its life cycle without it

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