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

Temperature in the body and homeostatis, discuss homeostatis. I have choose...

discuss homeostatis. I have choosen the bodies temperature and I need to discuss it and what effects it has on the body

Define ward planning, Question 1 Illustrate the concept of Economic Ord...

Question 1 Illustrate the concept of Economic Order Quantity Question 2 Omega Healthcare is planning to open a hospital in North Bangalore region. For this purpose t

Physico-chemical properties of niacin, Important physico-chemical propertie...

Important physico-chemical properties of niacin and niacinamide are as follows: a)  Niacin is a white crystalline solid. b) While niacin  is sparingly soluble in water, etha

Mapping science and survey, 1. (a)what is plane table traversing (b)with...

1. (a)what is plane table traversing (b)with illustration ,elaborate how you would map an area using the technique

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

Experiment of a bottle barometer, A bottle barometer A bottle, partiall...

A bottle barometer A bottle, partially filled with water, is overturned with its neck under the surface of more water in a saucer. This is the device used as a chicken feeder,

Decline of the bronze age civilisation, Decline of the Bronze Age Civilisat...

Decline of the Bronze Age Civilisation: We find that the great developments in production methods that came with the rise of early cities lasted only f6r a few centuries. The

Why do dark colours absorb heat?, Question 1 Outline the risks of nuclear ...

Question 1 Outline the risks of nuclear fissions Question 2 Comment on semiconductor devices and their usage Question 3 In a total system approach, what are the various

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