Blood & RBCs Flashcards
What is Blood & the Characteristics of Blood (5)
1) ONLY Liquid Connective Tissue in the body
2) 8% of total body weight
3) Consistency= thick, viscous (higher gravity than distilled water)
4) Color= ranges from Scarlet red (oxygen-rich) to dark red (oxygen poor)
Normal pH, Volume, & Temp of Blood
- pH= 7.4 (ranges from 7.35-7.45)
- Volume= Men= 5-6 L (1.5 gal) & Women= 4-5 L (1.2 gal)
- Temp= 38 degrees Celsius (aka 100.4 degrees F)
Blood functions (3)
1) Transportation (gases, nutrients, hormones, etc.)
2) Regulation (of pH, temp, water balance & electorlyte balance)
3) Protection (via WBCs, antibodies, & blood clotting)
Components of Blood & their blood volume %
Blood Plasma (55%) & Formed elements (45)
Characteristics & Components of Blood Plasma
- Fluid component of blood, slightly yellow
-90% water & 10% solutes
What makes up the solutes found in blood plasma? (5)
1) Electrolytes (most abundant)–> Na, K, Ca, etc.
2) Plasma proteins (AGF)
3) Nutrients (glucose, amino acids, glycerol, etc)
4) Respiratory gases (O2 & CO2)
5) Hormones
What plasma proteins are found in the solutes of blood plasma? (3)
- found only in blood plasma & synthesized in the liver
1) Albumin (60%
2) Globulin (36%)
3) Fibrinogen (4%)
What are the formed elements in blood and how many are there?
1) Erythrocytes (RBCs) = 4.2-5.8 million
2) Leukocytes (WBCs) = 5,000-9,000
3) Thrombocytes (Platelets) = 250,000-400,000
Hematopoiesis & Pluripotent Hematopoietic Stem Cells
- Blood cell production
- located in Red Bone Marrow, where all blood cells develop from
Characteristics of Erythrocytes (RBCs) (6)
1) 99% of all formed elements (blood cells) in circulation
2) Major contributor to viscosity
3) Biconcave, disc shaped
4) Anucleate= no nucleus
5) Amniotic= don’t divide
6) Flexible cell membranes with no organelles
7) Composed of mostly Hemoglobin
Why do RBCs not have mitochondria?
NO mitochondria = NO aerobic respiration (allows them to conserve all the O2 they carry so ALL their O2 is delivered to other cells)
Hemoglobin (3)
- 4 iron (heme) groups & 1 protein (globin) group
- Makes up about 1/3 of the weight & 97% of an RBC
- Gives RBCs red color
Hemocrit
% of total blood volume occupied by RBCs
What is the average number of RBCs & Hematocrit for men and women?
Men= 5.4 million per uL & 47%
Women= 4.8 million per uL & 42%
Hypoxia vs. Hyperoxia
-Hypoxia= not enough oxygen being delivered to tissue
-Hyperoxia= too much oxygen in the body which causes blood to become too viscous and clog small blood vessels
Erythropoiesis & rate & causes (3)
- RBC production
- produced at a rate of 2 million per second
1) Reduced number of RBCs
2) Insufficient Hemoglobin
3) Reduced availability of oxygen
Steps of Erythropoiesis (5)
1) Kidneys release REF enzyme into bloodstream
2) REF converts plasma proteins into Erythropoietin (hormone)
3) Erythropoietin circulates to red bone marrow & causes Proerythroblasts to begin RBC developmental process
4) Towards end of the development Reticulocyte develops (RBC precursor)
5) Reticulocyte enters bloodstream and develops into mature RBC in 1- 2 days
Stages of Erythropoiesis (5)
1) Kidneys –>REF enzyme
2) REF –> plasma proteins –> Erythropoietin
3) Erythropoietin –> Red bone marrow
4) PROerythroBLASTS –> Reticulocyte
5) Reticulocyte –> bloodstream = RBC in 1-2 days
REF
Renal Erythropoietic Factor
- released by Kidneys whenever low oxygen levels are detected
- Initiates Erythopoiesis
Erythropoietin
-Hormone that is slowly released from the liver (under normal conditions)
-During Erythropoiesis, converted from plasma proteins by REF to circulate into red bone marrow & causes preoerythroblasts to begin development of RBCs
Reticulocyte
- RBC precursor
-Anucleate (no nucleus) - Contains significant amounts of hemoglobin & several organelles
- Develop into mature Erythrocytes in 1-2 days
Reticulocyte Count
- Measures the rate of Erythropoiesis
- Number of retifulocytes in the bloodstream used as an indicator of the response of red bone marros to erythropoietin
- Normal count= 0.5-1.5% of all RBCs in a blood sample
How long do RBCs live in the bloodstream? Where are the removed/broken down?
- 120 days
- Old worn-out RBCs removed from by bloodstream and destroyed in the spleen & liver
How is Hemoglobin from old RBCs broken down?
1) Heme & Globin components are separated –> Globin broken down into amino acids (to make other proteins) & iron removed from heme
2) Iron from heme transferred to iron-storing proteins (Ferritin & Hemosiderin)
3) Iron proteins transported to red bone marrow from hemoglobin synthesis
4) Non-Iron portion of heme converted into Bilirubin
Ferritin & Hemosiderin
Iron-storing proteins that transport the iron carrying heme portion of hemoglobin from old RBCs to red bone marrow to be used for hemoglobin synthesis
Bilirubin
yellow-orange pigmented non-iron portion of heme transported from old RBCs into the liver where it’s secreted into bile
Erythrocyte Disorders
- caused by either blood loss, not enough RBCs, or too many RBCs being destroyed
- Anemia –> ability of blood to carry oxygen is reduced.
Hemorrhagic Anemia
- Anemia due to blood loss (EX: heavy period)
-Acute= rapid blood loss (EX: stab wound) - Chronic= slight, persistent blood loss (EX: bleeding ulcer)
Anemia due to decreased RBC or Hemoglobin production (4)
1) Aplastic Anemia- damage to red bone marrow
2) Iron-deficiency Anemia- reduced iron causes reduced hemoglobin production
3) Pernicious Anemia- lack of parietal stomach cells causes insufficient RBC production
4) Renal Anemia
Hemolytic Anemia (2 types)
- excessive loss of RBCs via hemolysis
1) Thalassemias
2) Sickle-Cell Anemia
