HUMAN PHYSIOLOGY
BODY FLUIDS AND CIRCULATION
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
Leucocytes
|
|
RBCs
|
|
Blood platelets
|
|
None
|
Detailed explanation-1: -Platelets, or thrombocytes, are small, colorless cell fragments in our blood that form clots and stop or prevent bleeding. Platelets are made in our bone marrow, the sponge-like tissue inside our bones. Bone marrow contains stem cells that develop into red blood cells, white blood cells, and platelets.
Detailed explanation-2: -Platelets are produced from very large bone marrow cells called megakaryocytes. As megakaryocytes develop into giant cells, they undergo a process of fragmentation that results in the release of over 1, 000 platelets per megakaryocyte.
Detailed explanation-3: -Platelets are not true cells, but are instead classified as cell fragments produced by megakaryocytes. Because they lack a nucleus, they do not contain nuclear DNA. However, they do contain mitochondria and mitochondrial DNA, as well as endoplasmic reticulum fragments and granules from the megakaryocyte parent cells.
Detailed explanation-4: -In humans, it includes plasma (the liquid portion), blood cells (which come in both red and white varieties), and cell fragments called platelets.