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

Planets., What are all the planets in our solar system?

What are all the planets in our solar system?

Science and technology during the renaissance, Science and Technology durin...

Science and Technology during the Renaissance:  This phase in the history of science was one of description and criticism. First came the exploration of ancient knowledge, mainly o

, What is the distance of the sun from eart

What is the distance of the sun from earth

Explain the mucous membrane, Explain the Mucous Membrane This layer is ...

Explain the Mucous Membrane This layer is lined by the epithelial cells. Parts of the tract which are subject to mechanical injury, the layer consists of stratified squamous ep

Clothing materials, clothing materials and their respective qualities

clothing materials and their respective qualities

Floating in different liquids, Floating in different liquids Obtain a t...

Floating in different liquids Obtain a tall, slender glass jar, test tube or bottle, and the following liquids: mercury, carbon tetrachloride, water and kerosene. You will also

Factor for hypothalamic control of anterior pituitary gland, Define Factors...

Define Factors for hypothalamic control of anterior pituitary gland Thyrotropin Releasing Factor (TRF) which causes release of TSH. Corticotropin Releasing Factor (CRF

Explain the horizons - oap, Explain the following horizons:   i...

Explain the following horizons:   i)   Oap   ii)   Btk i)  Organic horizon (O) with organic material that has undergone decomposition (a) and has been disturbed or

Objectives of disposal of chemical wastes, Objectives After observing t...

Objectives After observing the demonstration experiments, you should be able to: 1.  State the need for understanding the characteristics of a chemical waste before disposin

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