Blood Flashcards
What are the major components of blood?
- plasma
- cellular elements
What are the 3 cellular elements of blood?
- RBC (erythrocytes)
- WBC (monocytes, granulocytes (basophils, neutrophils, eosinophils), lymphocytes)
- platelets (thrombocytes)
What are the functions of blood?
transport
- respiration
- nutrition
- excretion
- homeostasis
- communication
protection
- hemostasis
- immune
What is the respiration function of blood?
transports O2 and CO2 between lungs and tissue
What is the nutrition function of blood?
transports nutrients from gut to tissues, between organs
What is the excretion function of blood?
transports metabolic waste to kidneys, intestines, or lungs for removal
What is the homeostasis function of blood?
maintaining body fluid volume, pH, and temperature
What is the communication function of blood?
transport of hormones
What is the hemostasis function of blood?
prevention of blood loss
What is the immune function of blood?
plasma and blood cells are involved in immune response
What is the composition of blood volume?
plasma volume (no cells): 55-60%
hematocrit (red blood cells): 40-45%
buffy coat (white blood cells, platelets): < 1%
What cells does plasma contain?
none
What cells does hematocrit contain?
RBC
What cells does buffy coat contain?
WBC
platelets
What is blood volume?
plasma volume + hematocrit
~ 5.5 L ≈ 3.0 L plasma (55%) + 2.5 L hematocrit (45%)
What happens to plasma volume in dehydration?
loss of plasma volume
What are 2 conditions with altered hematocrit?
- anemia
- polycythemia
What happens to hematocrit in anemia?
less RBCs to carry oxygen
- decreases viscosity (thins) blood
What is a symptom of anemia?
fatigue due to reduced oxygen delivery (less oxygen-carrying capacity)
What is polycythemia?
more RBCs
- increases viscosity of blood – thicker