Blood Physiology Flashcards
part of extracellular fluid
Blood
Extracellular fluid differentiated into
Plasma and interstitial fluid
Plasma and cells
Blood
The role of blood in internal environmental
homeostasis
The percentage of total blood volume that blood cells occupy
Hematocrit
normal value of hematocrit for male, female, and newborn:
40-50%, 37-48%, 55%
Cellular components of blood
Red Blood Cells (Erythrocytes)
White Blood Cells (Leucocytes)
Platelets (Thrombocytes)
98% water + ions + plasma proteins e.g. (Albumin, globulin, fibrinogen)
Plasma
Same ionic composition as interstitial fluid
Plasma
Specific gravity of total blood, plasma, and RBC
total blood - (1.050-1.060) more influenced RBC
plasma - (1.025–1.030) more influenced by plasma protein
RBC - (1.090-1.092) more influenced by Hb
Viscosity of blood and plasma
Blood relative viscosity (4~5) mainly depends on the numbers of red blood cells
Plasma relative viscosity (1.6~2.4) is mainly involved in plasma protein
Plasma osmotic pressure
300 mmol/L or 770 kPa
results from NaCl and modulates water distribution between inside and outside of cells
Crystal osmotic pressure
results from albumin and regulates water distribution between inside and outside of capillary
Colloid Osmotic Pressure
Plasma pH value
about 7.35-7.45
Functions of blood
Transport (O2, CO2, nutrient, hormones, waste product)
Homeostasis (Regulation of body temperature, ECF, pH)
Protecting against infections (White Blood Cells, Antibodies)
Blood Clotting prevent blood loss
Blood Volume
5 liter in adult:
45% is packed cells volume (PCV)
55% is plasma volume
Formation of RBC (erythrocytes)
Erythropoiesis
Formation of WBC (leucocytes)
Leucopoiesis
Formation of platelets (thrombocytes)
Thrombopoiesis
The forming processes of erythrocyte (red blood cell, RBC), leukocyte (white blood cell, WBC) and thrombocyte (platelet, P) originating from hematopoietic stem
Hemopoiesis
Flat biconcave disc, non-nucleated, Diameter 7-8 umx2.5umx1 um, Flexible, average volume 90-95 um^3, number = 4.7 - 5x10^6, Hb = 14-16 g/dl in the blood
Red blood cells
Production of red blood cells: In-utero
- Early few weeks of embryo nucleated RBCs are formed in yolk sac
- Middle trimester mainly in liver, spleen, and lymph nodes
- Last months RBCs are formed in bone marrow of all bones
Production of red blood cells: After birth
- Bone marrow of flat bone continue to produce RBC into adult life
- Shaft of long bone stop to produce RBC at puberty while epiphysis continued