Which of these statements is not true regarding platelets?
a. During maturation megakaryocytes undergoes endomitotic nuclear division
b. Thrombopoietin is mainly produced by liver
c. Lifespan of platelets is 7–10 days
d. They extrude their nucleus before forming mature platelets
The statement that is not true regarding platelets is:
d. They extrude their nucleus before forming mature platelets
This is incorrect because platelets do not have a nucleus. Platelets are derived from megakaryocytes through a process where megakaryocytes fragment their cytoplasm to form platelets, and the platelets themselves do not have a nucleus to extrude. The other statements are accurate:
a. True: During maturation, megakaryocytes undergo endomitotic nuclear division, which results in a polyploid nucleus.
b. True: Thrombopoietin is mainly produced by the liver.
c. True: The lifespan of platelets is typically 7–10 days.