Blood: Hematocrit and WBC

What is hematocrit?

the percentage of total blood volume occupied by RBCs

What is the normal range of hematocrit in adult females?

38-46

What is the normal range of hematocrit in adult males?

40-54%

What is hypoxia?

the direct stimulus for production of RBCs (in kidney cells)

Hypoxia → erythropoietin?

hypoxia stimulates the synthesis of EPO, a hormone by the kidneys, that stimulates the production of RBCs

What is anemia?

significant drop in hematocrit, blood has reduce O2 carrying capacity 

What is polycythemia?

increase in the % of RBC, hematocrit is above 54%

Polycythemia caused by:

dehydration and doping by athletes

What is a pluripotent stem cell:

RBM cells that have the capacity to develop into different precursors of cells 

What is a myeloid stem cell?

begin and complete development in RBM, makes all cells except lymphocytes

Myeloid stem cells differentiate into?

progenitor cells

What are progenitor cells?

precursor cells of blood elements, known as colony forming units 

What is the lymphoid stem cell?

begins dev in RBM, finishes in lymphatic tissues, give rise to lymphocytes

What is erythropoiesis?

the production of RBCs in the RBM

(EP) What is the precursor cell of the RBC, what does it do?

proerythroblast, divides and produces cells that begins synthesizing hemoglobin

(EP) When does a proerythroblast become a reticulocyte? 

when the nucleus is ejected 

When do reticulocytes usually develop into X, after X days from release of X

erythrocytes, 1-2 days release from RBM

What is the precursor thrombocytes, how does it become a TBC?

megakaryocyte is the precursor, cell is broken up and membranes come back together and form platelets

What are the functions of the platelets?

form platelet plug, release chemical promoting muscular spasm and blood clotting 

How are WBC classified?

granular or agranular leukocytes

What are the granular leukocytes?

neutrophils, eosinophils, and basophils

What are the agranular leukocytes?

lymphocytes and monocytes

(GL) Neutrophils function (the most)

phagocytosis to combat against pathogens and foreign substance

What do neutrophils contain?

defensins 

When chemotaxis is released X is the first there

neutrophils

(GL) Eosinophils

combat histamine effects from allergic reaction, fight against parasitic worms and phagocytize antigen-antibody complexes

(GL) Basophils

release histamine, heparin, and serotonin in allergic reactions, enhancing inflammation 

(AL) Lymphocytes: Functions and what are the types?  (second most)

mediate immune responses and antigen-antibody reactions

T cells, B cells, and NK cells 

(L) What are T-cells

attack foreign substances, formed in thymus 

(L) What are B-cells

develop into plasma cells to secrete antibodies, formed in the bone marrow

(L) What are NK-cells

attack infectious microbes and tumor cells

(AL) Monocytes: what do they differentiate to?

migrates from blood to tissues, enlarge and differentiate into macrophages 

Monocytes: function

phagocytosis after transforming into fixed or wandering macrophage 

What is a wondering macrophage?

roams tissues and gathers at sites of infection/inflammation through chemotaxis 

What is a bone marrow biopsy?

test RBM