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

Procedure for disposal op carcass, Procedure 1 . After the dissection e...

Procedure 1 . After the dissection experiment is over the dead animals are put in disposable paper bags and the bag is sealed. Animal tissues and excreta should also be put and

Depletion of ozone layer, Depletion of Ozone Layer: Since  the last dec...

Depletion of Ozone Layer: Since  the last decade or so, there is concern about the possible reduction in the ozone layer surrounding  the earth. Now the question arises, what h

Chemistry in golden era, Chemistry in golden era: Chemistry In the fiel...

Chemistry in golden era: Chemistry In the field  of metallurgy  too  we notice some remarkable developmenk. Before the close of the sixteenth century, zinc was isolated by a pr

Endomitosis, why and where endomitosis happen?

why and where endomitosis happen?

food plant engineeringsystems, water at 20 degree cellsuis is flowing a ra...

water at 20 degree cellsuis is flowing a rate of 20 L/minute through a 5 cm is internal diameter pipe. the viscosity of water at this temperatures is 0.98c cP. calculate the reynol

Moisture from breathing, Moisture from breathing Moisture coming from b...

Moisture from breathing Moisture coming from breathing might be shown by blowing on a cool mirror or into a cool glass or bottle.

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