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

Differences between tumor staging and tumor grading, Describe the differenc...

Describe the differences between tumor staging and tumor grading, and how each is performed. Relate the role of your particular imaging modality in staging and or grading, if any

Explain neutral fats, Explain Neutral fats Neutral fats are esters o...

Explain Neutral fats Neutral fats are esters of fatty acids with glycerol  and  found abundantly in  nature. These are  insoluble  in water but  readily  soluble in  ether,

Define the categories of soil structure, Define the categories of Soil stru...

Define the categories of Soil structure Three broad categories of soil structure.   These are:  1)  Single grained, where each particle in a soil functions as an indivi

Enzymes of intestinal juice, Enzymes of intestinal  juice Aminopepetid...

Enzymes of intestinal  juice Aminopepetidase is an  exopeptidase and cleaves peptide bonds next  to N-terminal amino acids of polypeptides and oligopeptides (unlike carboxypept

Isomers having same molecular form, Isomers are different  compounds' hav...

Isomers are different  compounds' having  same  molecular form  but  different structural forms. a) Glucose and Fructose b)  Glucose and Galactose

Define contribution of eosinophils, Define Contribution of Eosinophils ...

Define Contribution of Eosinophils They are specifically equipped to deal with a lot of parasites (all helminth worms). The coating of helminthes and some complement components

Define goitre - thyroid gland, Define Goitre - Thyroid Gland Goitre or ...

Define Goitre - Thyroid Gland Goitre or the enlargement of thyroid gland is one of the critical manifestations of iodine deficiency. Iodine, as you must have realized by now, i

Check-in sequences for treatment of the spillage site , Check-in Sequences ...

Check-in Sequences At the time of opening the lab, the following need to be kept in mind: 1.  Ensure that the door locks have not been tampered. If any tampering is detected

EMR, Explain how EMR waves are transverse?

Explain how EMR waves are transverse?

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