Blood I (as a fluid)

Question 1

Blood

Answer 1

Transports nutrients, respiratory gasses, wastes, hormones, and regulates temperature

pH: 7.35-7.45

Protection: WBCs and plasma proteins

Question 2

Centrifuged Blood

Answer 2

Plasma: 55%
RBC / Hemocrit (Ht): 45%
Buffy Layer: <1%

Question 3

Blood (fluids)

Answer 3

~7% of Body Mass
~ 5L in standard
ECF (plasma): 2.75 L
ICF (inside RBC): 2.25 L

Question 4

Blood Volume Terminology

Answer 4

Normal Volume = Normovolemia
Lower Blood Volume = Hypovolemia
Higher Blood Volume = Hypervolemia

Question 5

Composition of Plasma

Answer 5

1. > 90% water
2. Ions: Na+,K+, (Ca++, Mg++),Cl-,HCO3-, (PO4–)
3. Nutrients, Respiratory Gasses, Wastes Glucose, Amino Acids, Lipids, O2, CO2, Urea, Lactic Acid
4. PROTEINS (colloids) = 7%
   Albumins, Globulins, Fibrinogen

MAY BE APPROX BY 0.9% NaCl

Question 6

Separating Plasma Proteins

Answer 6

1. Differential Precipitation by Salts 2. Sedimentation in Ultracentrifuge
2. Electrophoretic Mobility
3. Immunological Characteristics

Question 7

Electrophoresis

Answer 7

fractionation method based on movement of charged particles along a voltage gradient

Question 8

Rate of electrophoresis

Answer 8

Influenced by…
1. Number / distribution of charges
3. Molecular Weight of proteins

Each protein migrates at its own characteristic rate

Question 9

Serum

Answer 9

Plasma containing NO fibrinogen
(clotting factors removed)

Question 10

Origin of plasma proteins

Answer 10

Synthesized in Liver: Albumin, Fibrinogen, (a1, a2, B) Globulins

Lymphoid Tissue: Gamma (Y) Globulin

diseased liver = plasma protein decrease

Question 11

Plasma protein and disease

Answer 11

diseased liver = plasma protein decrease

renal disease = decreased Albumin

infection = increased Gamma (Y) Globulin (antibodies)

Question 12

Plasma Protein Properties

Answer 12

7 g% Total

Albumin 4 g%
-smallest (MW: 69 kDa)
~20 mmHg (COP)
most easily lost

Globulins 2.7 g%
-medium and diverse (MW: 90-800)
~ 5 mmHg

Fibrinogen 0.3 g%
-Long and larger (MW: 350)
~ <1 mmHg

Question 13

Plasma proteins

Answer 13

1. Control transcapillary dynamics
2. Distribute fluid between plasma and ISF
   (Capillary wall is impermeable to proteins)

Question 14

Colloidal Osmotic Pressure (C.O.P) of Plasma

Answer 14

25 mm Hg
plasma proteins exert osmotic pressure across capillary wall

-If COP increases water flows into plasma
-If COP decreases water flows into ISF

Question 15

Filtration / Bulk Flow

Answer 15

Bulk Flow: flow of molecules subjected to a pressure
Filtration: bulk flow across a porous membrane which withholds some particles

Question 16

Starling Forces (Transcapillary Dynamics)

Answer 16

1. Filtration: pressure pushes fluid from capillaries into the ISF
2. Osmotic Flow: plasma proteins osmotic pressure pulls fluid into capillaries

Question 17

Diffusion vs Starling Forces

Answer 17

Diffusion: exchange of nutrients, gases, and wastes

Starling Forces: distribution of volume between plasma and ISF

Question 18

Capillary Bed

Answer 18

site where exchanges between plasma and ISF take place

Gradient of hydrostatic pressure
Higher at arterial end than venous end

Question 19

Starling’s Transcapillary Dynamics

Answer 19

Filtration occurs in arterial ends
Absorption occurs in venous ends

1. C.O.P. exerts 25 mmHg into capillaries
2. Filtration from blood pressure at arterial ends: 35 mmHg
3. Filtration from blood pressure at venous ends: 15 mmHg

Net filtration at arterial = 10 mmHg
Net absorption at venous = -10 mmHg

Question 20

Fluid filtered out

Answer 20

~90% of the fluid filtered out is reabsorbed back into capillaries
10% is drained from the tissues by lymphatic vessels

Question 21

Lymphatic Vessels

Answer 21

The walls of lymphatic vessels are made up of a single layer of endothelial cells
Highly permeable to all ISF constituents including proteins (leaking from plasma)

Question 22

Lymphatic vs Blood Flow Volumes

Answer 22

Total Blood Flow = 6,000 L
Volume filtered into ISF = 20 L
Volume returned by absorption = 17 L
Volume returned by lymph drainage = 3 L

Question 23

Protein contribution to C.O.P.

Answer 23

Based on number of osmotically active particles/unit volume
NOT their configuration/size/charge

1. Directly related to concentration in the plasma
2. Inversely related to the molecular weight of that protein

Albumin is biggest contributor

Question 24

Factors in Transcapillary Dynamics

Answer 24

1. Hydrostatic Pressure
2. C.O.P.
3. Capillary Permeability
4. Lymphatic Drainage

Question 25

Edema

Answer 25

accumulation of excess fluid in the interstitial spaces due to decreased venous return

Caused by…
1. Increased Hydrostatic Pressure
2. Decreased Plasma Protein (i.e., C.O.P.)
3. Increased Capillary Permeability
4. Obstruction of Lymphatic Drainage (Elephantiasis)

Question 26

Role of plasma proteins

Answer 26

1. Determines the distribution of fluid between plasma and ISF by starling forces
2. Contributes to viscosity of plasma (viscosity determine blood pressure)
3. Contributes to buffering power of plasma pH ~ 7.4

Question 27

Roles of specific Plasma Proteins

Answer 27

Fibrinogen: clotting
Y-Globulins: antibodies resistance to infection
Albumin and some globulins: act as carriers for lipids, minerals, hormones