Difference Between Megakaryocyte and Platelet

Two megakaryocytes in bone marrow, marked with arrows. A megakaryocyte (mega- + karyo- + -cyte, "large-nucleus cell") is a large bone marrow cell with a lobated nucleus responsible for the production of blood thrombocytes (platelets), which are necessary for normal blood clotting.

1. How do megakaryocytes produce platelets?
2. Do platelets come from megakaryocytes?
3. How do you identify a megakaryocyte?
4. What does megakaryocyte mean?
5. What organ makes platelets?
6. What is the normal lifespan of platelets?
7. What are the 3 functions of platelets?
8. Why platelets do not have nucleus?
9. Where platelets are destroyed?
10. What is another name for megakaryocyte?
11. Where is the principal site of Haematopoiesis in adults?
12. Which blood cells are called thrombocytes?

How do megakaryocytes produce platelets?

Megakaryocytes are produced from stem cells in the bone marrow by a process called thrombopoiesis. Megaryocytes create platelets by releasing protoplatelets that break up into numerous smaller, functional platelets. Thrombopoiesis is stimulated and regulated by the hormone thrombopoietin.

Do platelets come from megakaryocytes?

Platelets are formed and released into the bloodstream by precursor cells called megakaryocytes that reside within the bone marrow. The production of platelets by megakaryocytes requires an intricate series of remodeling events that result in the release of thousands of platelets from a single megakaryocyte.

How do you identify a megakaryocyte?

Megakaryocyte progenitors can be readily identified in bone marrow by immunoperoxidase and AChE labeling. Although both human megakaryocyte colony-forming and burst-forming cells express the CD34 antigen, only colony-forming cells express the HLA-DR antigen.

What does megakaryocyte mean?

Megakaryocytes are cells in the bone marrow responsible for making platelets, which are necessary for blood clotting. ... Megakaryocytes grow so large because the DNA within the cell duplicates many times — but without the cell undergoing cell division: a process called endomitosis.

What organ makes platelets?

Platelets are produced in your bone marrow.

What is the normal lifespan of platelets?

If they are not activated, consumed in clots, or cleared via disease processes, human platelets have an average circulation lifespan of 8–10 days (29, 54).

What are the 3 functions of platelets?

Platelets have the following functions:

• Secrete vasoconstrictors which constrict blood vessels, causing vascular spasms in broken blood vessels.
• Form temporary platelet plugs to stop bleeding.
• Secrete procoagulants (clotting factors) to promote blood clotting.
• Dissolve blood clots when they are no longer needed.

Why platelets do not have nucleus?

Activated platelets are round with projections. Like red blood cells, platelets are derived from myeloid stem cells. Some of these stem cells develop into megakaryoblasts, which give rise to cells called megakaryocytes in the bone marrow. ... Because they are not cells, platelets don't have their own nuclei.

Where platelets are destroyed?

Under conditions of TCP, the spleen and liver are the sites for accelerated platelet destruction, and in thrombocytosis, the spleen can become a supplemental breeding ground for megakaryocytes, in addition to the bone marrow space.

What is another name for megakaryocyte?

In humans, megakaryocytes usually account for 1 out of 10,000 bone marrow cells, but can increase in number nearly 10-fold during the course of certain diseases. Owing to variations in combining forms and spelling, synonyms include megalokaryocyte and megacaryocyte.

Where is the principal site of Haematopoiesis in adults?

In adults, hematopoiesis of red blood cells and platelets occurs primarily in the bone marrow. In infants and children, it may also continue in the spleen and liver.

Which blood cells are called thrombocytes?

Thrombocytes are pieces of very large cells in the bone marrow called megakaryocytes. They help form blood clots to slow or stop bleeding and to help wounds heal. Having too many or too few thrombocytes or having platelets that don't work as they should can cause problems.