BLOOD Flashcards
What percentage of the body mass is blood?
7%
How many litres of blood are in the body?
5L
What are the functions of Blood? (3)
Transport
Acid-Base Balance
Protective
What are the transport blood functions?
Nutritive, Respiratory, Excretory, Hormone Transport
What are the acid-base balance blood functions?
Regulation (normal ph range of 7.30-7.45)
What are the protective blood functions?
Some blood cells, and some blood proteins
What is blood composed of?
Plasma, Buffy Layer, RBCs
Normal Blood Volume
Normovolemia
Lower Blood Volume
Hypovolemia
Higher Blood Volume
Hypervolemia
What is the composition of plasma?
90% water Ions (0.9% NaCl) Nutrients Respiratory Gases Proteins
3 Types of plasma proteins
Albumins. Globulins, Fibrinogen
Hematocrit
Percentage of Blood Volume occupied by Red Blood Cells
4 ways to separate Plasma Proteins
- Differential Precipitation by salts
- Sedimentation in an ultracentrifuge
- Electrophoretic Mobility
- Immunological Characteristics
What is electrophoresis?
Fractionation method based on the movement of charged particles along a voltage gradient
Rate of Migration
is influenced by # and distribution of charges and molecular weight of each protein
% of Albumins
60
% of Globulins
35
% of Fibrinogen
5
Origin of plasma proteins in the liver?
Albumin, Fibrinogen, a1,a2, B Globulin
Origin of plasma proteins in the lymphoid tissue?
Y globulin
The ___ is the origin of each type of plasma protein except Y globulins
liver
What happens to plasma proteins if the liver is diseased
plasma proteins decreased
What happens to plasma proteins during a renal disease?
decrease of Albumin
What happens to plasma proteins during a bacterial infection?
increase of Y (gamma) globulin
Net Flow
for water to move
the difference in osmotic pressure
Only __________ solutes contribute to the effective osmotic pressure
Non-Diffusible
What solutes do not contribute to the effective osmotic pressure? Why?
Diffusible
Plasma Proteins are diffusible/non-diffusible
non-diffusible
Exerting an osmotic effect
colloidal osmotic pressure
What is the colloidal osmotic pressure of plasma?
25 mm Hg
What happens when the colloidal osmotic pressure of plasma increases?
water flows into plasma
What happens when the colloidal osmotic pressure of plasma decreases?
water will flow into ISF
What is the role of plasma proteins? (3)
- Determines the distribution of fluid between the plasma and ISF by controlling transcapillary dynamics
- Contribute to the viscosity of plasma by maintaining blood pressure
- Contribute to the buffering power of plasma to maintain normal pH 7.30-7.45
Is there protein diffusion across the capillary wall
No protein diffusion
What is the major contribution to the colloidal osmotic pressure?
No protein diffusion across the capillary wall
What does the colloidal osmotic pressure of plasma determine?
Amount of water into or out of capillaries
Bulk Flow
- hydrostatic pressure difference between the compartments
- flow of molecules subjected to a pressure difference
2 Transcapillary Dynamics
Filtration
Osmotic Flow
What does filtration do?
tends to push out the fluid from inside the capillaries
What does osmotic flow do?
due to plasma proteins and tend to pull in or retain fluid inside capillaries
The magnitude of bulk flow
hydrostatic pressure difference
What type of forces are filtration and osmotic flow?
starling forces
what do starling forces determine?
The distribution of ECF volume between the plasma and ISF
Diffusion
The exchange of nutrients, gases, and wastes across the capillary wall
The main organ in the circulatory system
Heart
Capillary Bed
the site where exchanges take place between plasma and ISF
Arterial
Blood enters capillaries
Venous
Blood exits capillaries
Net filtration pressure
the total pressure that promotes filtration
Net absorption pressure
the total pressure that promotes absorption
where do exchanges take place?
along the whole length
What percentage of fluid filtered out is reabsorbed directly back into the capillary?
90%
What percentage of fluid filtered out is drained by lymphatic vessels?
10%
Lymphatic System
- network of blind-ended terminal tubules
- coalesce to form lymphatic vessels
- converge to form large lymphatic ducts
- drain into large veins in the chest
Order of plasma protein concentrations
Fibrinogen < Globulins < Albumin
Order of plasma protein molecular weight
Albumin < Globulins < Fibrinogen
Order of plasma protein C.O.P
Fibrinogen < Globulins < Albumin
Most abundant plasma proteins
Albumin
Proteins exert osmotic pressure
- related to
- inversely related to
related to concentration
inversely related to molecular weight
Factors of Transcapillary Dynamics (4)
- hydrostatic pressure
- C.O.P
- capillary permeability
- lymphatic drainage
Edema
Accumulation of excess fluid in the interstitial spaces
Conditions that lead to edema
increased hydrostatic pressure
decreased plasma protein - (C.O.P)
increasing capillary permeability
obstruction of lymphatic drainage
Why does hydrostatic pressure increase?
Net filtration increases
Net absorption decreases
Why does C.O.P. decrease?
Failure to synthesize plasma proteins (Liver disease)
Loss of protein (Kidney disease)
Severe protein malnutrition (KWASHIORKOR)
Why does capillary permeability increase?
The capillary wall becomes more permeable
- more plasma proteins escape into ISF
- which exert an oncotic effect
How does lymphatic drainage become obstructed?
Elephantiasis resulting from parasite infestation
Fibrinogen and some globulins are essential to _________
clotting
Y-globulin provides
specific resistance to infection
Albumin and some globulins act as
carriers for lipids, minerals, hormones
- cholesterol, iron, steroid hormones
Types of Blood Cells
Red Blood Cells - erythrocytes
Platelets - thrombocytes
White Blood Cells - Leukocytes
Size of Red Blood Cells
7.2μ
Size of Platelets
2-3μ
Size of White Blood Cells
10-18μ
Order the size of the 3 Blood Cells
Platelets < Red Blood Cells < White Blood Cells
The lifespan of Red Blood Cells
120d
The lifespan of Platelets
7-8d
The lifespan of White Blood Cells
hrs-yrs
Cytokines
substances that are released by one cell and affect the growth and development and activity of another cell
What do cytokines influence
Proliferation and differentiation of blood cell precursors - hematopoietic growth factors
Prenatal Sites of Hematopoiesis
Liver and spleen
Postnatal Sites of Hematopoiesis
Axial skeleton, distal long bones, flat bones of skull, shoulder blades, pelvis, vertebrae, sternum, ribs, rounded end of long bones
Complete blood count
RBC, WBC, platelet, Hb concentration
Function of RBCs
facilitate the transport of respiratory gases between lungs and cells
What are blood cells derived from?
Multipotential stem cell, committed stem cells
What is the RBC shape
biconcave disk
What is the RBC shape due to?
presence of (spectrin) a fibrous protein
Advantage of the biconcave disk
maximal surface area and minimal diffusion distance for its volume
a high degree of flexibility
What is the benefit of the high degree of flexibility of biconcave disk shape
allows cells to squeeze through narrow capillaries
Cell size and shape can change in _______ states
diseased
RBC have no __________
subcellular organelles
True/False: In RBC, the rate of production = the rate of destruction
True
Composition of RBC
Water, Hb, Lipids, proteins and ions
Structure of Hemoglobin Structure
Betta chain, alpha chain, Heme, Iron
How does RBC generate energy?
ATP anaerobically
RBC have important _____ systems
Enzyme
Glycolytic Enzymes
Generate energy
Carbonic Anhydrase
CO2 Transport
Each molecule of Hb can bind to ___ O2 molecules
4
In lungs, Hb becomes _____
saturated with O2
In tissues, O2 ______
dissociates from Hb
Hemoglobin Functions
- Transport of O2
- Transport of small amounts of CO2 –> attached to polypeptide chains
- Act as a buffer
Factors affecting Hemoglobin to bind and release O2 (5)
- Temperature
- Ionic composition
- pH
- pCO2
- Intercellular Enzyme Concentration
Red Cell Precursors Differentiation
Decrease in size, loss of nucleus, progressive accumulation of Hb
What can an injection of bone marrow stem cells reconstitute?
All hematopoietic cell types
Myeloid and lymphoid stem cells are under the influence of
HGFs (cytokines)
Reticulocytes have some ______ ___
Some residual RNA
Normal Reticulocytes Count (meaning and %)
amount of effective erythropoiesis in bone marrow, <1 %
What is a reticulocyte?
immature RBC
Factors determining # of RBCs
O2 requirements
O2 availability
Erythropoietin
a glycoprotein hormone/cytokine produced largely by the kidney (renal cortex)
Release of Erythropoietin
stimulated by hypoxia
- from decreased RBC count
- decreased O2 availability
- increased tissue demand for O2
Hypoxia has been produced by
recombinant DNA technology
Regulation of Erythropoietin
- To maintain homeostasis
- Erythropoietin released in presence of hypoxia stimulates the bone marrow to produce more RBCs
Erythropoietin is a ________ feedback loop
negative
Hormonal effects on erythropoietin
- Testosterone increases the release of erythropoietin, increases the sensitivity of RBC precursors to erythropoeitin
- Estrogen has opposite effects
Lifespan of RBCs
120 days
Can anything prolong the RBCs lifespan
No
How is old RBCs recognized and removed from circulation?
By highly phagocytic cells (macrophages)
What happens to Bilirubin after macrophage?
Liver –> intestimal tract
What happens to Globin after macrophage?
Amino acid pool
What happens to Iron after macrophage?
Transferrin –> ferritin storage –> bone marrow –> reused in RBC
What is jaundice?
yellowing of the skin
Jaundice is due to _________
hyperbilirubinemia
Causes of Jaundice (3)
exessive hemolysis
hepatic damage
bile duct obstruction
Clinical indices
Number of RBCs
Amount of Hb
Hematocrit (Ht)
Hematocrit
Percentage of Blood Volume occupied by Red Blood Cells
Anemia
decrease in oxygen-carrying capacity blood
Polycythemia
Less plasma volume
Physiological Polycythemia
increased physical activity
at high altitudes
chronic lung disease
heavy smoking
Pathological Polycythemia
Tumours of cells producing Erythropoietin
Unregulated production by Bone Marrow
What results from polycythemia
increase blood viscosity
blood clots
What results from anemia
decreased RBC count
Hb Content
What do subjects of anemia look like?
pale, tired, weak
Microcytic
<80μ^3
Normocytic
80-94μ^3
Macrocytic
> 94μ^3
Normochromic
33%
Hypochromic
<33%
Causes of Amenias
- Diminished Production
- Ineffective Maturation
- Increased Destruction
Diminished Production results from:
Abnormal site (radiation, drugs) Abnormal stimulus (renal disease) Inadequate raw materials (iron deficiency)
Ineffective Maturation results from:
Deficiencies of Vitamin B12 and Folic Acid
Where does Vitamin B12 absorption occur?
Intrinsic Factor Deficiency
- pernicious anemia
in ileum
Increased Destruction results from:
toxins, drugs, and antibodies
The total amount of iron in the body
4g
Daily intake in Diet
15-20 mg
Where is Iron in the body? %?
Hb 65% Stored 30% Myoglobin 5% Enz 1%
Hemorrhage
Loss of Blood
Hematoma
Accumulation of blood in tissues
Two types of hemorrhage
external internal (into tissues)
Hemostasis
The arrest of Bleeding following vascular injury
Primary Hemostasis
Vascular response and platelet response
Secondary Hemostasis
Clot Formation
T/F Platelet response is only important in primary hemostasis
False, Platelet response is important in both primary and secondary hemostasis
Steps of Vascular Injury
Vasoconstriction
Platelet Plug Formation
Blood Clot Formation
Vasoconstriction
- Opposed endothelial cells stick together
- Smooth muscle cells in vessel wall respond to injury by contracting
Platelet Response
Platelet Plug of white thrombus
How does vasoconstriction occur?
After releasing of vasoconstricting agents
Platelet Structure
2-4 um diameter
No nucleus
Many granules
Many filaments, microtubules, mitochondria, sER
Purpose of granules
factors for vasoconstriction, platelet aggregation, clotting, growth
Platelet Life Span
7-10d
Where does platelet production occur?
Committed stem cell in Bone marrow
Thrombopoietin mostly from liver
Platelets from Bloodstream
Platelet factors are released and attract ______
more platelets
4 steps of Platelet Plug formation
- adhesion
- activation and release of cytokines
- aggregation
- consolidation
What is adhesion facilitated by
Von Willebrand factor
Platelet functions (5)
Release of vasoconstricting agent form platelet plug release clotting factors participate in clot retratction promote maintenance of endothelial integrity
Petechiae
small red/purple spot caused by bleeding into the skin
Abnormal primary hemostatic response
Prolonged Bleeding
Prolonged Bleeding can occur from ________ and _______
failure of the blood vessels to constrict and platelet deficiencies
Platelet deficiencies occur due to (2)
numerical <75,00/ul thrombocytopenia
functional —> congenital or acquired by drugs, toxins, antibodies
Thrombus
Blood clot
Are RBC and WBC needed for clotting?
No
Clot formatrion is a function of ________
Plasma
Clotting is innitiated by injury to ________
blood vessel wall
Clotting results in __________ in presence of ____
activation and interaction of group of plasma proteins and clotting factors in presence of calcium ions and some phospholipid agent
Tissue Factors (prot & phospholipid) released from damaged cells (Intrinsic or Extrinsic Pathway)
Extrinsic Pathway
Exposed Collagen (Intrinsic or Extrinsic Pathway)
Intrinsic Pathway
Damage to the blood vessel (Intrinsic or Extrinsic Pathway)
Intrinsic Pathway
Damage to tissue outside vessel (Intrinsic or Extrinsic Pathway)
Extrinsic Pathway
How long does the Intrinsic Pathway take?
3-6 min
How long does the Extrinsic Pathway take?
15-20 seconds
How is clotting kept in check?
inhibitors of platelet adhesion and anticoagulants
What do clotting pathways produce?
prothrombin –> thrombin
fibrinogen –> fibrin
Generate large quantities of thrombin (Intrinsic or Extrinsic Pathway)
Intrinsic Pathway
Generate rapid small amounts of thrombin (Intrinsic or Extrinsic Pathway)
Extrinsic Pathway
Anticoagulants
naturally occurring chemicals which block one or more of the reactions of the coagulation scheme, thereby inhibiting the coagulation scheme
Factors in Coagulation
Ca++
Phospholipids
Protein Plasma Factors
Clotting Factor Deficiencies can be from _____ or ______
congenital or acquired
Congenital Clotting Deficiencies
Hereditary deficiencies of a single factor (haemophilia)
Acquired Clotting Deficiencies
Usually multifactor deficiencies
- liver diseases
- vitamin K deficiency
What does clot retraction depend on?
presence of a contractile protein (thrombasthenia) released by platelets
Serum
plasma without fibrinogen and other clotting factors
Clot lysis (Fibrinolysis)
Dissolve blood clots
Anticoagulant Drugs
Coumadin
Heparin
Thrombolytic Drugs
Tissue plasminogen activator
Streptokinase
Inhibitors of Platelet Adhesion
Aspirin
Intrinsic Proactivitors
Endothelial Cell Factors
Extrinsic Proactivitors
Tissue Factors
pernicious anaemia
Vitamin B12 deficiency
Classification of aplastic anaemia
Normocytic, Normochromic
Classification of stimulation failure anaemia
Normocytic, Normochromic
Classification of iron deficiency anaemia
Microcytic, Hypochromic
Classification of Maturation
Failure Anemia
Macrocytic, Normochromic
Anemia that might be accompanied by jaundice
Hemolytic Anemias
Clot Retraction depends on presence of
contractile protein (thrombosthenin) released by platelets.
Serum is plasma without
fibrinogen and
other clotting factors