AP BIOLOGY

Detailed explanation-1: -Neutrophils are produced in the bone marrow from stem cells that proliferate and differentiate to mature neutrophils fully equipped with an armory of granules. These contain proteins that enable the neutrophil to deliver lethal hits against microorganisms, but also to cause great tissue damage.

Detailed explanation-2: -Neutrophils mature in the bone marrow in about 2 weeks. In the first half of this period, the neutrophil precursor cells undergo six divisions and differentiate from myeloblasts through promyelocytes to neutrophil myelocytes (Figure 1).

Detailed explanation-3: -Neutrophils are produced inside of the bone marrow (BM) through progressive maturation of hematopoietic progenitors (long-term hematopoietic stem cells [LT-HSCs] to GMPs). Proliferative precursors (NeP and preNeu) differentiate into immature neutrophils and finally into mature neutrophils that are released into blood.

Detailed explanation-4: -“We have identified the stem cells that are the early origins of neutrophils, the most abundant blood cell type in humans, ” said Huy Dinh, PhD, a former LJI postdoctoral associate who is currently at the University of Wisconsin-Madison.

Detailed explanation-5: -Neutrophil exit from the bone marrow Mature neutrophils are kept in the bone marrow through the action of two chemokine receptors, CXCR2 and CXCR4.