describing blood physiology and blood components in details describe wbc, rbc ,platelets and plasma proteins as well as functions of blood

1. TEXT BOOKS
 Essentials of Medical Physiology – Indu
Khurana
 Concise Medical Physiology – S.Chaudhari
 Medical Physiology - Sembulingam

2. REFERANCE BOOK
 Guyton
 Medical Physiology by A K Jain
 Ganong

3.  HUMAN BODY COMPRISES 60-65% OF WATER .
 IN FEMALE LOW WATER CONTENT BECAUSE OF
FAT.
 IN OBESE LOW WATER CONTENT BECAUSE OF
FAT.
 FLUIDS PRESENT IN THE BODY EITHER
INTRACELLULAR OR EXTRACELLULAR.
 EXTRACELLULAR FLUIDS ARE :-
1. PLASMA 2.CSF
3. INTRAOCULULAR FLUID
4. SEROUS FLUID
5. FLUID IN URINARY TACT.
6. IN BONES AND CARTILAGES.
INTRODUCTION

4. IMPORTANCE OF BODY FLUIDS
 FLUID IS IMPORTANT TO MAINTAIN
NORMAL INTERNAL & EXTERNAL
ENVIRONMENT FOR FUNCTION OF
TISSUE & CELLS , TARNSPORTATION,
METABOLIC REACTION & TEMPERATURE
REGULATION.
 DECREASE IN BODY FLUID IS
DEHYDERATION.

5. BLOOD
 FLUID CONNECTIVE TISSUE.
 FLUID OF LIFE.
 FLUID OF GROWTH.
 FLUID OF HEALTH.
PROPERTIES : 1. COLOUR - RED
2. VOLUME - 5 LITERS
3. REACTION - P.H. 7.4
4. SPECIFIC GRAVITY - 1.52 TO 1.061
5. VISCOSTITY - 5 TIMES MORE THAN
WATER.

9. COMPOSITION OF BLOOD
 HEMATOCRIT VALUE:-
BLOOD +ANTICOGULANT,IN
HEMATOCRIT TUBE,AT 3000/RPM
CENTRIFUGED LEADS TO PLASMA +RBC.
 PLASMA - TOP LEVEL - 55% - STRAW
COLOURED.
 RBC BOTTOM – 45%.
 BUFF COLOURED LIQUID IN BETWEEN
DUE TO WBC AND PLATELETS.

10. FUNCTIONS OF BLOOD
 THERE ARE 8 FUNCTIONS OF BLOOD.THEY
ARE:-
1. NUTRITIVE.
2. RESPIRATION.
3. TRANSPORT OF HORMONES AND ENZYMES.
4. REGULATION OF WATER BALANCE.
5. REGULATION OF ACID-BASE BALANCE.
6. REGULATION OF BODY TEMPERATURE.
7. STORAGE FUNCTION.
8. DEFENSIVE FUNCTION.

11. RED BLOOD CELLS( RBC)
 BLOOD = PLASMA + FORMED ELEMENT.
 FORMED ELEMENTS INCLUDES RBC,
WBC AND PLATELETS.
 RBC’S :-
1. ERYTHROCYTES. RED BLOOD CELL
(RBC )
2. NON NUCLEATED.
3. RED COLOUR IS DUE TO HAEMOGLOBIN.

12. 1. 7.2 micron DIAMETER.
2. BICONCAVE. Why ?
3. THICKNESS-1micron TO 2.2micron.
4. SURFACE AREA 120 Sq micron.
8 4 to 5.5 million/ cu.mm of blood

14. Composition of red blood cell
 Cell membrane and sponge like stroma
 Water,
 Lipids
 Protein
 Lipoprotein
 Enzymes of glycolytic system
 Glucose and amino acids
 Cl, phosphate, bicarbonate are in large amount
 Non protein nitrogenous substances.

15. Metabolism in red blood cell
 Glucose is taken inside the cell by
facilitated diffusion
 EMBDEN MEYERHOF pathway – 90% of
glycolysis
 HEXOSE MONOPHOPHATE SHUNT –
10% oxidation of glucose

16. Properties of the red blood
cells
 Rouleaux formation.
 Packed cell volume
 Suspension stability
When blood is taken out of the blood vessels the red
blood cells pile up one above another like the pile
of coins. This property of the red blood cells
called rouleaux formation

18. Packed cell volume
 When the blood is colleted in a centrifuge
tube along with proper anti coagulant for a
period of 30 minutes at a speed of a 3000
rpm ( revolution per minute ) , red blood
cells settle at the bottom of the tube leaving
the clear plasma at the top. The red blood
cells form 45 % of the total blood. This is
called packed cell volume or hematocrit.
The volume of plasma is 55 %.

20. Suspension stability
 During circulation red blood cell remain
suspended uniformly in the blood. This
property of the red blood cell is called the
suspension stability.

21. Red cell indices
 Mean corpuscular volume (MCV)
 Mean corpuscular haemoglobin (MCH)
 Mean corpuscular haemoglobin
concentration (MCHC)

22. Mean corpuscular volume (MCV)
 PCV in 1000ml of blood (PCV. 10)
RBC count / cmm
=450/ 5= 90 cubic micron
 Normal- normocytosis
 Decreased value – microcytosis
 Increased value – macrocytosis

23. Mean corpuscular haemoglobin
(MCH)
 MCH = Hbgm/L / RBC count /liter
 It is the average weight of Hb in each RBC
 Normal value is 30 pg
 Increased in spherocytosis and
megaloblastic anemia

24. Mean corpuscular haemoglobin concentration
(MCHC)
 Here amount of Hb is expressed as
percentage of volume of RBC
 Hb in gm% /PCV/ 100ml
 Normal is 33.3%
 Hypochromia
 Hyperchromia is rare

25. Physiological variation
 Increase in the red blood cell count is called
polycythemia. If it occur in physiological
condition , it is called physiological
polycythemia. It occur in the following
condition :

26. 1. Age
At birth the red blood cell count is
6to 7millions/ cu mm of blood.
The count decrease within 10 days
after birth due to lysis of cells
causing physiological jaundice in
some infants.
However , in infants and growing
children the cell count is at a higher
level than the value in adults.

27. 2. sex
Before puberty and after
menopause in female the red
blood cell count is similar to that
in males.
During reproductive period of
females , the count is less than in
males (4.5 millions/ cu mm )

28. 3. High altitude
The inhabitants of mountain ( above
10,000 feet from mean sea level ) have
an increased red cell count of more
than 7 million / cu mm.
This is due to hypoxia at high altitude.
During hypoxia, erythropoietin is
released from the kidney. The
erythropoietin in turn stimulates the
bone marrow to produce more red
blood cells.

29. 4. Muscular exercise
There is temporary increase in the
red blood cell count after
exercise. This is because of mild
hypoxia and contraction of
spleen, which is the reservoir of
blood.

30. 5. Emotional condition
The red blood cell count is
increased during the emotional
condition like anxiety ; because
of sympathetic stimulation.

31. 6. Increased environmental
temperature
The increase in the atmospheric
temperature, increase red blood
cell count.

32. 7. After meals
There is a slight increase in the red
blood cell count after taking meals.

33.  Decrease in the red blood cell
count occur in the following
physiological conditions :

34. 1. High barometric pressures
 At high barometric pressures as in deep
sea, when oxygen tension of blood is
higher , the red blood cell count
decreases.

35. 2. After sleep
 The red blood cell count decrease slightly
after sleep.

36. 3. Pregnancy
 In pregnancy, the red blood cell count decrease.
 This is because of increase in extracellular fluid
volume.
 Increase in extra cellular fluid volume leads to
increase the plasma volume resulting in
hemodilution. So there is a relative reduction in
the red blood cell count.

37. Pathological variation
 Pathological polycythemia : the abnormal
increase in the red blood count is called
polycythemia. The red cell count increase
above 7 millions/ cu mm of the blood.
Polycythemia are of 2 types.
1) primary polycythemia
2) secondary polycythemia

38. Primary polycythemia or
polycythemia vera
 It is a disease with persistent increase in the red
blood cell count above 14 millions/cu mm of
blood.
 This is always associated with increase level of
white blood cell count above 24,000 / cu mm of
blood.
 Polycythemia vera occur in myeloproliferative
disorders like malignancy of red bone marrow.

39. Secondary polycythemia
 This is secondary to some of the pathological
conditions which produces chronic hypoxia
 1) respiratory disorder like emphysema.
 2) congenital heart disease
 3) chronic carbon monoxide poisoning
 4) poisoning by chemicals like phosphorus and
arsenic
 5) repeated mild hemorrhages.

40.  Pathological decrease in RBC
count is anemia.

41. Life span and fate of red blood cells
 Average life span of the red blood cells is 120 days. The
senile red blood cells are destroyed in reticuloendothelial
system. (tissue macrophage system)
 Littoral cells in bone marrow
 Kupffer cells in liver
 In the spleen
 In the lymph node

42. Destruction of RBS mainly occur in spleen.
The diameter of the capillaries in spleen is
less or equal to that of red blood cell. The
younger red blood cell can pass through the
capillaries easily.
However , because of fragile nature , the
older cells are destroyed while trying to
squeeze through the capillaries due to
decreased NADPH activity.
So the spleen is usually called graveyard of
the red blood cell.

43.  The destroyed red blood cell are fragmented. From the
fragmented part hemoglobin is released. The iron and
globin part of the hemoglobin are separated with the
production of bilirubin. Iron combines with the protein –
apoferritin to form ferritin, which is stored in the body.
Globin also enters the protein depot. The bilirubin is
excreted by liver through bile.
 Daily 10 % red blood cell ,which are senile which get
destroyed in normal young healthy adult. This cause
release of about 0.6 g % of hemoglobin in to the plasma.
From this 0.9 to 1.5 mg % bilirubin is formed.

44. Functions of red blood cell
 1) Erythrocyte transport oxygen from the lungs to the
tissues. The hemoglobin in the red blood cell combines
with oxygen and 97 % of oxygen is transported as
oxyhemoglobin.
 2) Red blood cell transport carbon dioxide from the tissues
to the lungs. The hemoglobin the red blood cell combine
with carbon dioxide and form carbhemoglobin.
 3)Hemoglobin in the red blood cell also function as a good
buffer.
 4) Red blood cell carry the oxygen group antigens like A
agglutinogen , B agglutinogen and Rh factor. This help in
determination of blood group and blood transfusion.

45. ANEMIA
 Basically it is the condition when the
hemoglobin content of blood is decreased
below normal level.

46. Classification of anemia
 Anemia can classify in 2 type :
 1) morphological and 2) etiological
 MORPHOLOGICAL : on the basis of size and
morphological content of red blood cell the anemia classify
in 4 type.
 A) normocytic normochomic anemia
 the size of red blood cell and hemoglobin content of red
blood are normal. Only red blood cell count is reduce.
 B) macrocytic normochromic anemia :
 the red blood cell are larger in size and due to this red cell
count is reduce. The hemoglobin content is normal.

47.  C) macrocytic hypochromic anemia :
 the red blood cell are immature and larger in size,
and the hemoglobin content in the cell is less. (
MCH – mean corpuscular hemoglobin. )
 D) microcytic hypochromic anemia :
 the red blood cell are similar in size.the
hemoglobin content in the red blood cell are less
( MCH )

48. ETIOLOGICAL CLASSIFICATION
 On the basis of etiology anemia is divided
into 4 types.
 1) hemorrhagic anemia
 2) hemolytic anemia
 3) nutrition deficiency anemia
 4) aplastic anemia

49. Hemorrhagic anemia
 Anemia occur in both acute and chronic hemorrhagic
condition. Hemorrhage occurs in condition like accident,
ulcer , excessive uterine bleeding purpura and hemophilia.
 Acute hemorrhage : during acute hemorrhage there is a
reduction in total rd blood cell count. The quantity of
plasma portion of blood is replaced within 24 hours.
However replacement of red blood cells, takes some
time.with less number of red blood cell the hemodilution
occurs. This type of anemia is called normocytic
normochromic anemia as both the size and hemoglobin
content of red blood cell are normal. This condition is
corrected after 3 to 4 weeks when red blood cell are
produce dure to the stimulation of bone marrow.

50. Chronic hemorrhage
 During chronic hemorrhage due to continuous loss
of blood a lot of iron is lost from the body. The
quantity of iron available in the diet is also
limited. So the synthesis of hemoglobin is
affected. The cell do not contain adequate amount
of hemoglobin and the size of the cell decreases.
Hence, this type f anemia is known as
hypochromic and micocytic anemia.

51. Hemolytic anemia
 Hemolysis means excessive destruction of the red blood
cell, which occur due to various cause :
 1) chemical poisoning by substances like lead, coal and
tar.
 2) infection like malaria and septicemia
 3) presence of chemical hemolysins
 4) presence of isoaggutinins like anti Rh
 5) congenital or acquired default in the shape of red blood
cells.
 When the shape of red blood cell is abnormal these cell
become more fragile and hemolysis occur easily. This
occur in two inherited condition called sickle cell anemia
and thalassemia.

52. Sickle cell anemia
 It is congenital anomaly and found mostly in blacks . It is
due to the abnormal hemoglobin called hemoglobin S. in
this the alpha chain are normal and beta chain are
abnormal. The molecules of the hemoglobin S polymerize
in to the long chain and precipitate inside the cells.
Because of this red blood cell attain sickle cell and become
more fragile leading to hemolysis.
 In children , hemolyzed sickle cell aggregate and block the
blood vessel leading to infarction. The infarction is
common in bones. The infarcted small bones in hand and
foot result in varying length in digits. This condition is
known as hand and foot syndrome. Jaundice also occur in
this children.

53. Thalassemia
Thalassemia is of 2 type namely alpha and beta thalassemia.
 in normal hemoglobin number of alpha and beta poly
peptide chain is equal. In thalassemia production of these
chain become more imbalanced because of defective
synthesis of globin genes. These causes the precipitation of
the poly peptide chain in the immature red blood cells
leading to distribution in erythropoiesis. The precipitation
also occur in immature red cells resulting in hemolysis.

54.  Among the 2 type beta thalassemia is very common. In this
beta chain are less In number absent or abnormal and there
is an excess of alpha chains. Alpha chain precipitate
causing defective erythropoiesis hemolysis. the alpha
thalassemia occur in fetal life or infancy. In this alpha
chain are less, absent or abnormal with the excess of
gamma chains. These lead to defective erythropoiesis or
hemolysis. The infant may be stillborn or may die
immediately after birth.

55. Nutrition deficiency anemia
 Iron deficiency anemia : iron deficiency anemia develops
due to inadequate availability of iron for hemoglobin
synthesis. The red blood cell are microcytic and
hypochromic. Iron deficiency occur because of the
following reason :
 1) loss of blood
 2) decrease intake of iron
 3) poor absorption of iron from intestine
 4) increase demand for iron in condition like growth and
pregnancy. The special feature of iron deficiency anemia
are brittle nails , spoon shape nails , brittle hair , trophy of
papilla in tongue and dysphagia.

56. Protein deficiency anemia
 Due to deficiency of protein the synthesis of hemoglobin is
reduced. Hence, the cell are hypochromic.
 Pernicious anemia or addison’s anemia
 it is due to the atrophy of the gastric mucosa resulting in
production of intrinsic factor and poor absorption vitamin
B12. atrophy of gastric mucosa may occur because of
autoimmune destruction of parietal cells. The red blood
cell are larger in size. Before knowing the cause of this
anemia , it was very difficult to treat the patient and the
disease consider to be fatal. So, it was called pernicious
anemia. The synthesis of hemoglobin may be normal
almost this type of anemia. The cells are macrocytic and
normochromic.

57.  Pernicious anemia is common in old age and it is more
common in females than in males. This is associated with
other autoimmune disease like disorder of thyroid gland,
addison’s disease. The characteristic feature of this anemia
are lemon yellow color of skin and red sore tongue. ( due
to anemic pallor and mild jaundice ) neurological disorder
such as paresthesia , progressive weakness and ataxia are
also observed in extreme condition.

58. Megaloblastic anemia
 This is due to deficiency of another maturation factor
called folic acid. Folic acid deficiency occur because of
poor intake or poor absorption. The maturation of cell does
not occur. The red blood cell are larger with normal nuclei.
The nucleus remain immature because of defective DNA
synthesis. The reason of defective DNA synthesis is lake of
folic acid or abnormal folic acid metabolism. In this type
the cells are macrocytic and hypochromic.
 The feature of pernicious anemia appear in megaloblastic
anemia also. However neurological disorder may not
develop.

59. Aplastic anemia
 Aplastic anemia is due to the disorder of red bone
marrow. The red bone marrow is reduced and
replaced by fatty tissue conditions like repeated
exposure to X – ray or gamma ray radiation and
by bacterial toxin, quinine, gold salts, benzene,
radium etc. it is common in tuberculosis and viral
infections like hepatitis and HIV infections. The
cells are normocytic and normochromic.

60. Signs and symptoms of anemia
 1) skin : the color of the skin become pale. The paleness is
more constant in bucal and pharyngeal mucus membrane ,
conjunctivae , lips , ear lobes , palm and nail bed. Skin
becomes thin and dry loosing the elasticity. Thinning , loss
and early grayness of hair occur. The nail become brittle
and easily breakable.
 2) cardiovascular system : - in anemia , there is increase in
heart rate and cardiac out put. Heart is dilated and cardiac
murmurs are common. The velocity of blood flow is
increase.

61.  3) respiration : there is increase in force and rate of
respiration. Some times , this leads to breathlessness and
difficulty in breathing ( dyspnea ) oxygen hemoglobin
dissociation curve is shift to right.
 4) digestion : the common symptoms are anorexia , nausea
, vomiting , abdominal discomfort and constipation. In
pernicious anemia there is atrophy of papillae in tongue. In
aplastic anemia , necrotic lesions appear in mouth and
pharynx.

62.  5) metabolism : basal metabolic rate is increase in severe
anemia.
 6) kidney : renal function is disturb. Albuminuria is
common.
 7) reproductive system : in females, the menstrual cycle is
disturbed. There may be menorrhagia , oligomenorrhea or
amenorrhea.
 8) neuromuscular system : the common neuromuscular
symptoms are headache , lack of concentration ,
restlessness , irritability , drowsiness , dizziness or vertigo
especially when standing , increased sensitivity to cold and
fainting sensation. Muscles become weak and the patient
feels lack of energy and fatigued quite often and quite
easily.