Lecture 16: Blood 1-3 Flashcards
Blood transports (4)
- O2 from the lungs to the cells of the blood and vice versa
- Nutrients from GI tract to body cells
- Heat and waste products away from the cells
- Hormones from endocrine glands to other body cells
Blood helps to regulate body temperature by
Mainly increasing or decreasing blood flow to the skin for heat exchange
Blood helps to regulate pH through
Buffers
Example:
-Hemoglobin combines with CO2
-Hemoglobin binds H+ ions
Blood helps to regulate electrolytes and water in body fluids by
Influencing dissolved protiens
Pc
Capillary hydrostatic pressure
Pi
Interstitial hydrostatic pressure
(pi)c
Capillary osmotic pressure
(pi)i
Interstitial osmotic pressure
Prevention of blood loss through
clotting
Combats microorganisms and other substances through
white blood cells or specialized plasma proteins
Viscosity of blood vs. water
Because blood contains red blood cells, it is thicker and heavier than water and also flows more slowly than water
Temperature of blood
- Slightly higher than body temperature
- Absorbs heat generated by active skeletal muscle and redistributes it to other tissues
Slight alkalinity of blood
- pH is between 7.35 and 7.45
- Arterial blood is more alkaline than venous because it has less CO2
Plasma proteins normally remain in
plasma
How do plasma proteins act as buffer systems
- Free carboxyl groups (-COOH) at one end of the protein acts like an acid by releasing H+ when pH arises
- Free amino group (-NH2) at the other end of a protein can act as a base by combining with H+ ions when the pH falls
Plasma proteins establish osmotic gradient between
Blood and interstitial fluid
Osmotic pressure is the primary force responsible for
Preventing excessive loss of plasma from the capillaries into the interstitial fluid and thus helps maintain plasma volume
Three primary classes of plasma proteins
Albumin
Globulin
Fibrinogen
Albumins
- Make up 55% percent of plasma proteins
- Major contributors to the osmotic pressure of plasma
- Important in the transport of fatty acids
Globulins percentage
-Make up 38% of plasma proteins
Two types of globulins
- Transport globulins
- Immunoglobulins
Transport globulins
- Thyroid binding globulin (binds and transports thyroxine)
- Transcortin (transports ACTH and cortisol)
- Transferrin (transports ions)
- Lipoproteins (transports lipids)
- Steriod-binding proteins (transports steroid hormones like sex hormones)