what is the fate of hemoglobin in blood?

Answer 1

Hemoglobin is degraded by a range of enzymes once red blood cells become exhausted. The heme component contains the iron, which is essential for the body, and as such, is recycled and maintained in the body. Hemoglobin is converted bilirubin and then further to urobulin, which gives urine it's yellow colour (also the yellow colouration of the skin and eyes during an episode of icterus associated with disease such as hepatic cirrhosis), and feces its brown colour.

Answer 2

The "formed" elements of the blood of which the RBC(erythrocyte) is one are formed by a process known as hematopoesis(haemopoesis). These elements are formed in the red bone marrow in flat bones and ends of long bones in adults. Erythropoetin, a hormone released by the kidney, stimulates with Vit B12 the process of erythropoesis. The stem cell, haemocytoblast, differentites into a proerythroblast, then through various cellular changes and sequential mitotic divisions, becomes a "normoblast". In the intermediate normoblast hemoglobin begins to appear in the cytoplasm. The "late" normoblast is relased from the marrow into the bloodstream where it loses it's nucleus and becomes a reticulocyte then a mature erythrocyte which is an anucleated "biconcave" disc with an average life span of 120 days. Hemoglobin was the first oligometric protein to be subjected to x-ray analysis. It's molecular weight is 64,500 and contains 4 polpeptide chains and 4 heme prosthetic groups in which the iron atoms are in the ferrous state. The protein portion of hemoglobin consists of 2 alpha chains(141 residues each) and 2 beta chains(146 residues each). The hemoglobin molecule is roughly spherical with a diameter of 5.5nm. Each of the 4 chains has a tertiary structure in which the chain is folded. The 4 polypeptide chains fit together in a tetrahedral arrangement to make the characteristic quarternary structure. There is one heme group bound to each chain. The structure of hemoglobin "fits" well with the "biconcave" shape of the RBC. Hemoglobin binds oxygen in the alveolar capillaries of the lung and releases the carbon dioxide and delivers the oxygen at the tissue level during it's passage through capillary beds where it unloads the oxygen and loads the carbon dioxide. Oxyhemoglobin and carbaminohemoglobin(carboxyhemoglobin) are slightly different as conformational changes occur in the quarternary structure to accomodate the oxygen or carbon dioxide respectively. The "red pulp" of the SPLEEN has a framework of reticular tissue which acts as a reservoir for blood and contains phagocytic and reticuloendothelial cells which destroy worn out RBC's(about 120 days after formation).

Answer 3

Hemoglobin is contained in RBC (Red Blood Cells) which is a cellular component of blood. The life span of an RBC is 120 days. After 120 days, the RBC burst or phagocytised and the hemoglobin is released into the blood stream. Hemoglobin then is reduced into biliverdin and then into unconjugated biliruibn (B1). Blirubin is the major bile pigment. In the liver B1 is further conjugated to form bilirubin diglucuronide( B2 ) and then excreted through urine as urobilin and then in the stool (fecal material) in the form of urobilinogen.

Answer 4

This Site Might Help You.

RE:
what is the fate of hemoglobin in blood?

Answer 5

When boredom, depression, or perhaps stress causes cravings, find a nonfood way to meet them such as enjoying a walk, calling a friend, choosing a bath, reading a book, or even doing some yoga.

Answer 6

Muscle mass uses up more calories, so include three 20-minute strength-training sessions per week.

Answer 7

Add an extra five minutes for your cardio routine.

Answer 8

Mix up your routine to prevent weight-loss plateaus.

Answer 9

eat less total calories

Answer 10

Chapter 19 CVS: Blood

Objectives:

Describe the functions and contents of blood;
What is in plasma?
What are the various formed elements, their origin, their normal values and functions.
What terms are associated hematology (clinical pathology of blood) and what do they mean?
What is the fate of old RBC and its hemoglobin?
List the events involved in formation of a blood clot.
List the ABO blood types, the isoantigen(s) and antiobodiy(s) of each and possible transfusion and blood typing reactions (agglutination).
Describe the genetic determination of the Rh factor and transfusion risks.
What conditions lead to HDN (hemolytic disease of newborns?




I. Functions and Properties

A. Functions

1. Transport

2. Regulation

3. Protection (clotting, Phagocytosis, Immunity)

B. Volume – 8% of body weight

C. Components

1. Plasma

a. Proteins

i. Albumin

ii. Fibrinogen

iii. Antibodies (immunoglobulins)

b. Solutes

i. Gases

ii. Electrolytes

iii. Nutrients

iv. Wastes

v. Hormones



2. Formed elements

a. Eyrthrocytes (RBCs)

b. Leukocytes (WBCs)

c. Thrombocytes (platelets)



3. Packed Cell Volume (PCV or Hematocrit)

a. Normal values (about 40% formed elements)

i. Females 38-46%

ii. Males 40-54%



II. Hematopoiesis by red marrow

A. Pluripotent stem cells

1. Myeloid stem cell

a. Reticulocyte

i. Eyrthrocyte

b. Megakaryoblast

i. Platelets

c. Eosinophil

d. Basophil

e. Neutrophil

f. Monocyte (may become macrophage)

2. Lymphoid stem cell

a. T lymphocyte

b. lymphocyte (may become plasma cell)



B. Stimulants for hematopoiesis

1. Role of eyrthropoietin (produced by kidney) to stimulate RBC production

2. Role of thrombopoietin (produced by liver)

3. Role of cytokines (local production) to stimulate WBC production



III. Eythrocytes

A. General

1. Bi-concave disk

2. Blood type antigens

3. Hemoglobin (oxygen carrying protein) Normally 12-18 g/100ml of blood

a. 4 Heme groups

b. 2 Alpha polypeptides (globulins)

c. 2 Beta polypeptides (globulins)

4. 5.4 million/mm3 (ml) in males, 4.8 million/ml in females

5. production rate: 2 million/second

6. life expectancy of 120 days



B. End of RBC Life cycle

1. Old RBC damaged or lysed in circulation

2. Macrophages phagocytize

3. Liver and spleen

a. Globulins recycled as component amino acids

b. Heme broken down to iron component

i. Stored in muscle, live and spleen

ii. Iron reused by bone marrow to make new heme

c. Non-iron heme is converted to bilirubin and sent to liver

d. Bilirubin becomes bile pigment and secreted through gall bladder to small intestine

i. Some reabsorbed and becomes urobilinogen in urine

ii. Some becomes stercobilinogen in feces

C. Beginning of life cycle

1. New RBC release stimulated by erythtropoietin from kidney

2. Nucleated RBC

3. reticulocyte (reticulocyte count and anemia)



IV. Leukocytes (5K-10K/ml) Defensive cells

A. Granular (colored granules in cytosol)

1. eosinophil 2-4%

a. function: parasite defense, contribute histamine in inflammation so numbers increase in allergies

2. basophil <1%

a. Function: intensify inflammation

3. neutrophil (PMNs and Band cells) 60-70%

a. Function: are phagocytes, numbers increase in infection and stress. Attracted to damaged tissues by cheomtaxis

B. Agranular (no granules in Cytosol)

1. Macrophages 3-8%

a. Function: phagocytes, may become macrophages (tissue phagocytes) if wander out of CVS into tissues

2. Lyphocytes 20-25%

a. B lyphocytes mature in to plasma cells if stimulated by immune response and produce immunoglobulins

b. T lymphcytes are also stimulated by immune system to mature into various forms of T cells to help defend body

C. Clinical pathology terms

1. Leukocytosis-elevated leukocyte count usulay indicates defense against infection or malignancy (leukemia)

2. Leukopenia- lower than normal WBC count, usually bad, as not responding to infection or lose of WBCs

3. Differential WBC count (“diff”) quantitative discription of number of each WBC

4. CBC “complete blood count” “diff” plus RBC count, Hb, and PCV (“crit”)



V. Platelets and hemostasis (clotting) required for blood clotting

A. Magakaryocytes fracture in to 2000-3000 platelets

B. Normal count is 150,000-400,000/ml of blood

C. Smallest formed element

D. Blood clotting (hemostasis) following hemorrhage (bleeding)

1. Tissue damage and release of chemical mediators (prostaglandin, histamine, bradykinen, tissue factor)

2. Vascular spasm causes local vasoconstriction to slow hemorrhaging

3. Platelet plug formation

a. Platelet adhesion to damaged cells

b. Platelets activated (platelet release reaction) to form net of platelets and maintain vasospasm

c. ADP makes other platelets sticky to add to forming plug (platelet aggregation)

4. Formation of blood clot (coagulation)

a. Extrinsic pathway

i. TF from cells outside CVS, so “extrinsic”

ii. TF + Ca activate factor X , which combines with factor V to make active enzyme prothrombinase

b. Intrinsic pathway

i. From factors within (intrinsic to) blood

ii. Begins when endothelium is damaged so blood contacts collagen (basement membrane)

iii. Damaged platelets activated

iv. With Ca, factor X stimulated to combine with factor V, making prothrombinase

c. Common pathway

i. Prothrombinase converts prothrombin (factor II) to thrombin

ii. Thrombin converts soluble fibrinogen to insoluable fibrin threads. Thrombin also activates factor XIII to strengthen fibrin

iii. Positive feedback from thrombin to factor V to make more prothrombinase AND activate more platelets



d. Clot retraction

i. Fibrin threads plus platelets shrink and pull damaged tissues together, allows serum to escape but not formed elements

e. Role of Vitamin K is to synthesize 4 of the 13 clotting factors. Without Vitamin K there are essential clotting factors that cannot be made



5. Anticoagulant drugs delay or suppress

i. Heparin

ii. Warfarin (Coumadin) antagonists to Vitamin K

iii. EDTA in purple top tubes removes Ca

iv. Citrate phosphate (CPD) in blue tubes removes Ca



6. Intravascular clotting

a. Thrombus (clot) blocks vessel

b. Thrombosis (formation of thrombus)

c. Embolism any thing that block vessel (thrombus, air bubble, plaque)

d. DIC (disseminated intravascular clotting)



7. Thrombolytic agents dissolve thrombi (aspirin, streptokinase and t-PA) to treat CVA and MI



VI. Blood types

A. ABO groups of RBCs (isoantigens are glycoprotein and glycolipid tissue markers) are genetically determined

1. A isoantigen (blood type A) with B isoantibody

2. B isoantigen (blood type B) with A isoantibody

3. A and B isoantigens (blood type AB) with no isoantibody

4. No isoantigens (blood type O) with A and B isoantibody

5. transfusion reactions between donated cells isoantigen(s) and recipient’s isoantibodie(s)

6. Typing and cross matching



B. Rh Blood Group is also genetically determined

1. Dominant, Rh positive means Rh factor is present on RBCs

2. Recessive Rh negative means Rh factor is not present

3. Normally no antibodies are associated with RH factor unless an Rh negative person receives Rh positive blood so are exposed to the foreign antigen. No corresponding reaction in Rh+ person as there is no antigen on Rh- blood to cause an immune reaction

4. Hemolytic disease of newborns

a. Mom must be Rh negative and father Rh+ and fetus Rh+ fro mother to produce antibodies against Rh+ fetus