19-3 Red blood cells, formed by Erythoropoiesis, contain hemoglobin that be recycled

Hemoglobin structure is complex quaternary structure it contains 4 globular protein subunits each with?

1 molecule of Heme (a nonprotein pigment complex) 1 heme contains one iron ion which formes oxyhemoglobin formes because it interacts with oxygen.

RBC Formation and Turnover: ___% of circulating RBCs wear out per day. About ___ million new RBCs are produced per second.

1% 3 Million

Regulation of Erythropoiesis (RBCs formation): Building red blood cells requires?

1. Amino Acids 2. Iron 3. Vitamins B12, B6, and folic acid

Phagocytes break down hemoglobin into components: (1) Globular proteins break down into __? (2) Heme is stripped of iron and converted to?

1. Amino acids 2. Biliverdin

Hemoglobin Conversion and Recycling: 1. _____: hemoglobin breakdown products in urine due to excess hemolysis in bloodstream 2. _____: whole red blood cells in urine due to kidney or tissue damage. 3. ____ break down hemoglobin into components. (1) Globular proteins to amino acids (2) Heme stripped of iron, converted to Biliverdin

1. Hemoglobinuria 2. Hematuria 3. Phagocytes

What are the stages of RBC maturation? (5) M PERM (BPM under E)

1. Myeloid Stem Cell 2. Proerythroblast 3. Erythroblasts (basophilic; polychromatophilic; normoblast) 4. Reticulocyte 5. Mature RBC

Hemocytoblast (Hematopoietic stem cells), stem cells in myeloid tissue divide to produce?

1. Myeloid stem cells, become RBCs, some WBCs 2. Lymphoid stem cells, become lymphocytes

What are the 3 important effects of RBC shape on function.

1. high surface to volume ration (quickly absorbs and released oxygen) 2. Discs form stacks called Rouleaux (smooth the flow through narrow blood vessels) 3. Discs bend and flex entering small capillaries

RBCs use anaerobic metabolic and live about ___ days.

120 days (3 months)

In adult males, 1 microliter, or 1 cubic millimeter (mm3) of whole blood contains 4.5-6.3 million RBCs. In advil females, i microliter contains ____ million.

4.2-5.5

Function of Hemoglobin: Each RBC contains about 280 million Hb molecules. Because 1 Hb molecule contains 4 heme units, each RBC can potentially carry more than a billion molecules of oxygen at a time. Roughly __% of the oxygen carried by the blood is bound to Hb molecules inside RBCs

98%

Each red blood cells is a small highly specialized discs and is ____ with a thin central region and a thicker outer margin. Diameter: 7.8; max thickness: 2.85 but the center narrows to about 0.8.

Biconcave

Breakdown of Biliverdin: Biliverdin (green) is converted to _____ (yellow)

Bilirubin

Jaundice is caused by a buildup of ?

Bilirubin

The % of a blood sample that consists of formed elements (most of which are red blood cells) is known as the ______. The ______ is determined by centrifuging a blood sample so that all the formed elements come out of suspension. Whole blood contains about 1000 red blood cells for each white blood cell.

Hematocrit

The most abundant blood cells are the red blood cells (RBCs), which account from 99.9% of the formed elements. These cells give whole blood its deep red color because they contain the red pigment _____, which binds and transports oxygen and carbon dioxide.

Hemoglobin

___ is a protein molecule that transports Respiratory gases. Normal hemoglobin (adult male) 14-18 g/dL whole blood Normal hemoglobin (adult female) 12-16 g/dL whole blood

Hemoglobin (Hb)

Iron ions associate easily with oxygen to form ___ and dissociate easily from oxygen to form ___

Oxyhemoglobin HbO2 Deoxyhemoglobin

___ anemia is low RBC production, due to unavailability of vitamin B12

Pernicious anemia

Production of hemoglobin can be stimulated in adults using Hydoxyurea or Butyrate but two much of this can cause?

Sickle cell anemia and Thalassemia (which is bad)

Bilirubin is secreted by ___?

Liver (bile)

Hemoglobin Conversion and Recycling: ______ or liver, spleen, and red bone marrow monitor RBCs and Engulf RBCs before membranes rupture (Hemolyzed)

Macrophages

Bilirubin is converted by intestinal bacteria to ___ and __.

Urobilins & Stercobilins

RBCs lack what ?

nuclei, mitochondria, and ribosomes (so means no repair)

______, red blood cells formation takes place only in red bone marrow, or Myeloid Tissue in adults. This tissue is located in portions of the vertebrae, sternum, ribs, skull, scapulae, pelvis, and proximal limb bones. Stem cells mature to become RBCs. Under extreme stimulation, such as sever blood loss, areas of yellow marrow can convert to red marrow, increasing the rate of RBC formation.

Erythropoiesis

Stimulating Hormones: _______, formed by the kidney and liver. It is secreted when Oxygen in peripheral tissues is low (hypoxia). Usually due to disease or high altitude.

Erythropoietin (EPO) also called erythropoiesis-stimulating hormone.

Iron Recycling. Red blood cells developing in the red bone marrow absorb the amino acids and transferrin from the bloodstream and use them to synthesize new Hb molecules. Excess transferrin are removed in the liver and spleen, and the iron is stored in two special protein-iron complexes: ___ and ____.

Ferritin and Hemosiderin

___ hemoglobin = strong form of hemoglobin found in embryos. Takes oxygen from mothers hemoglobin.

Fetal Hemoglobin

Iron Recycling: Iron removed from heme leaving ____. To transport proteins it binds to Transferrin

Biliverdin

Hemoglobin Function: When plasma oxygen levels are low in peripheral capillaries, hemoglobin release oxygen and binds carbon dioxide and carries it to the lungs. The alpha and beta chains of hemoglobin then bind carbon dioxide forming ?

Carbaminohemoglobin