© BIOLOGY 2060 LECTURE NOTES
ANATOMY & PHYSIOLOGY II (A. IMHOLTZ) BLOOD P1 OF 4
Fluid connective tissue
Consists of cells suspended in a liquid fibrous matrix.
Blood cells = formed elements
Liquid matrix = plasma.
Formed elements consist of erythrocytes (red blood cells), leukocytes (white blood cells) and
Centrifuged blood divides into 3 portions
Packed RBCs (42-52% in ♂ and 37-47% in ♀.
This % = hematocrit.)
Buffy layer containing WBCs and platelets. (<1%)
Color ranges from scarlet (oxygen-rich) to dark red (oxygen poor).
Viscosity is 5x that of water, due primarily to the presence of formed elements.
pH normally ranges from 7.35-7.45 (slightly alkaline).
Temperature is typically 100°F.
Volume is 4-5 L for females and 5-6 L for males.
(from lungs) and nutrients (from GI tract and body stores) to all cells
Carries wastes from all cells to elimination sites (lungs for CO
; kidneys for nitrogenous wastes
Carries hormones (chemical signals) from endocrine organs to target tissues.
Regulates body T° by absorbing and distributing heat
Maintains body fluid pH by virtue of its many buffers
Maintains adequate body fluid volumes.
Prevents blood loss by initiating clotting mechanisms in response to blood vessel damage
Prevents infection via WBCs and plasma immune proteins.
48-58% of blood volume in ♂ and 53-63% of blood volume in ♀.
Water acts as a solvent and suspending medium.
Solutes dissolved in plasma include: plasma proteins, nutrients, electrolytes, respiratory gases,
hormones and wastes.
Albumin = most abundant plasma protein
Produced by the liver
Maintains plasma osmotic pressure.
Acts as a buffer and is involved in the transport of steroids and bilirubin.
Globulins are another major type of plasma protein.
Many are produced in the liver and act as transport proteins for lipids, metal
ions, and fat-soluble vitamins.
Other globulins, known as antibodies are produced during the immune response.
Most are produced in the liver, e.g., prothrombin and fibrinogen.
Absorbed from the GI tract or body reserves and distributed throughout the body.
E.g., amino acids, glucose, fatty acids, triglycerides, vitamins, and cholesterol.
Electrolytes (ions, such as Ca
, and K
Respiratory gases (dissolved CO
, and N
Wastes (byproducts of cell metabolism, e.g., urea, uric acid, ammonia, creatinine, and lactic acid)
Buffers (chemicals that function to prevent fluctuations in plasma pH)
Hormones (chemical messengers such as insulin or epinephrine).