Body Fluids and Circulation Class 11 Notes Biology Chapter 18

 Page 1


Points To Remember
Blood : A special connective tissue that circulates in principal vascular 
system of man and other vertebrates consisting of fluid matrix, plasma and formed 
elements (Blood = Plasma + All blood cells).
Plasma : (Blood – All blood cells = Plasma) The liquid part of blood which 
is straw coloured, viscous fluid and contains about 90-92% of water and 6-8% 
proteins.
Lymph : A clear yellowish, slightly alkaline, coagulable tissue fluid, 
containing white blood cells (Only lymphocytes), a liquid resembling blood 
plasma.
Serum : Blood plasma from which fibrinogen and other clotting factors 
have been removed. (Plasma– (fibrinogen & other clotting factor) = blood serum.
Heart Beat : The rhythmic contraction and relaxation of the heart, which 
includes one systole (contraction phase) and one diastole (relaxation phase) of 
the heart. Heart beat count of healthy person is 72 times per minute.
Stroke Volume : The volume of blood pumped out by the heart during a 
systole. If is approximately 70 ml.
Cardiac output : The amount of blood pumped by heart per minute is called 
cardiac or heart output. The value of cardiac output of a normal person is about 
72 × 70 = 5040 mL or about 5L per minutes.
Cardiac Cycle : The rhythmic contraction and dilation of different parts of 
heart in one beat.
Systole : Contraction of heart muscles.
Diastole : Relaxation of heart muscles
Page 2


Points To Remember
Blood : A special connective tissue that circulates in principal vascular 
system of man and other vertebrates consisting of fluid matrix, plasma and formed 
elements (Blood = Plasma + All blood cells).
Plasma : (Blood – All blood cells = Plasma) The liquid part of blood which 
is straw coloured, viscous fluid and contains about 90-92% of water and 6-8% 
proteins.
Lymph : A clear yellowish, slightly alkaline, coagulable tissue fluid, 
containing white blood cells (Only lymphocytes), a liquid resembling blood 
plasma.
Serum : Blood plasma from which fibrinogen and other clotting factors 
have been removed. (Plasma– (fibrinogen & other clotting factor) = blood serum.
Heart Beat : The rhythmic contraction and relaxation of the heart, which 
includes one systole (contraction phase) and one diastole (relaxation phase) of 
the heart. Heart beat count of healthy person is 72 times per minute.
Stroke Volume : The volume of blood pumped out by the heart during a 
systole. If is approximately 70 ml.
Cardiac output : The amount of blood pumped by heart per minute is called 
cardiac or heart output. The value of cardiac output of a normal person is about 
72 × 70 = 5040 mL or about 5L per minutes.
Cardiac Cycle : The rhythmic contraction and dilation of different parts of 
heart in one beat.
Systole : Contraction of heart muscles.
Diastole : Relaxation of heart muscles
Name and Number/ Structure Life Span and Function
Percentage Formation
(A) Erythrocytes RBCs Red colour Formed from birth Transport of oxygen
- 4.5 to 5.5 million Circular, biconcave onward by red bone and some amount
per cubic millimetre of denucleated, elastic marrow Life-120 days of carbon dioxide
blood lack of cell organelles excess RBCs are through haemoglobin
like ER, ribosomes, stored in spleen 
mitochondria etc.
(B) Leucocytes Colourless rounded Formed in red bone Acts as soldiers
(WBCs) 5000-8000 or irregular, marrow, Lymph scavenger and some
per cubic mm of nucleated 12 to nodes, spleen and help in healing
blood 20mm wide, life 1-4 thymus
days
(i) Agranulocytes Large rounded Lymph nodes, Non Phagocytic
(a) Lymphocytes 20-45% nucleus, 6-10 mm spleen, thymus red secrete antibodies
of leucocytes bone marrow, life few 
days to months or
even years
(b) Monocytes 6-8% of Largest of all (12-15 Red Bone marrow, phagocytic, very
leucocytes, mm) bean shaped life 10-20 hours motiles engulf
nucleus germs
(ii) Granulocytes 
(a) Eosinophils 2-3% bilobed nucleus, Red Bone marrow, play role in immunity
of leucocytes granules in cytoplasm life 4 to 8 hrs. in non phagocytic
blood
(b) Basophils 0-5% of Three lobed nucleus Red Bone marrow, release heparin and
leucocytes (s-shaped) life 4 to 8 hours in histamine
blood
(c) Neutrophils 60-65% Many lobed nucleus Red Bone marrow, phogocytic, engulf
of leucocytes fine granules life 4 to 8 hours in germ and dead cells
blood
(C) Platelets Colourless, rounded Red Bone marrow help in blood clotting
thrombocytes or oval, or irregular worm out ones
1,50,000-3,50,000 per non-nucleated phagocytized in blood
cubic mm of blood fragments
TYPES OF BLOOD CELLS THEIR NUMBER, STRUCTURE & FUNCTIONS
Page 3


Points To Remember
Blood : A special connective tissue that circulates in principal vascular 
system of man and other vertebrates consisting of fluid matrix, plasma and formed 
elements (Blood = Plasma + All blood cells).
Plasma : (Blood – All blood cells = Plasma) The liquid part of blood which 
is straw coloured, viscous fluid and contains about 90-92% of water and 6-8% 
proteins.
Lymph : A clear yellowish, slightly alkaline, coagulable tissue fluid, 
containing white blood cells (Only lymphocytes), a liquid resembling blood 
plasma.
Serum : Blood plasma from which fibrinogen and other clotting factors 
have been removed. (Plasma– (fibrinogen & other clotting factor) = blood serum.
Heart Beat : The rhythmic contraction and relaxation of the heart, which 
includes one systole (contraction phase) and one diastole (relaxation phase) of 
the heart. Heart beat count of healthy person is 72 times per minute.
Stroke Volume : The volume of blood pumped out by the heart during a 
systole. If is approximately 70 ml.
Cardiac output : The amount of blood pumped by heart per minute is called 
cardiac or heart output. The value of cardiac output of a normal person is about 
72 × 70 = 5040 mL or about 5L per minutes.
Cardiac Cycle : The rhythmic contraction and dilation of different parts of 
heart in one beat.
Systole : Contraction of heart muscles.
Diastole : Relaxation of heart muscles
Name and Number/ Structure Life Span and Function
Percentage Formation
(A) Erythrocytes RBCs Red colour Formed from birth Transport of oxygen
- 4.5 to 5.5 million Circular, biconcave onward by red bone and some amount
per cubic millimetre of denucleated, elastic marrow Life-120 days of carbon dioxide
blood lack of cell organelles excess RBCs are through haemoglobin
like ER, ribosomes, stored in spleen 
mitochondria etc.
(B) Leucocytes Colourless rounded Formed in red bone Acts as soldiers
(WBCs) 5000-8000 or irregular, marrow, Lymph scavenger and some
per cubic mm of nucleated 12 to nodes, spleen and help in healing
blood 20mm wide, life 1-4 thymus
days
(i) Agranulocytes Large rounded Lymph nodes, Non Phagocytic
(a) Lymphocytes 20-45% nucleus, 6-10 mm spleen, thymus red secrete antibodies
of leucocytes bone marrow, life few 
days to months or
even years
(b) Monocytes 6-8% of Largest of all (12-15 Red Bone marrow, phagocytic, very
leucocytes, mm) bean shaped life 10-20 hours motiles engulf
nucleus germs
(ii) Granulocytes 
(a) Eosinophils 2-3% bilobed nucleus, Red Bone marrow, play role in immunity
of leucocytes granules in cytoplasm life 4 to 8 hrs. in non phagocytic
blood
(b) Basophils 0-5% of Three lobed nucleus Red Bone marrow, release heparin and
leucocytes (s-shaped) life 4 to 8 hours in histamine
blood
(c) Neutrophils 60-65% Many lobed nucleus Red Bone marrow, phogocytic, engulf
of leucocytes fine granules life 4 to 8 hours in germ and dead cells
blood
(C) Platelets Colourless, rounded Red Bone marrow help in blood clotting
thrombocytes or oval, or irregular worm out ones
1,50,000-3,50,000 per non-nucleated phagocytized in blood
cubic mm of blood fragments
TYPES OF BLOOD CELLS THEIR NUMBER, STRUCTURE & FUNCTIONS
Biology Class - 11
Blood Pressure—The resistance offered by the lumen of the artery to the 
flow of  Blood.
Hypertension : The condition when blood pressure is higher than normal 
(120/80 mmHg)
Electrocardiograph : (ECG) the machine used to record electrocardiogram.
Electrocardiogram ECG : The print out of pattern of heart beat taken on 
a graph paper from Electrocardiograph. (EGC machine)
Lymph
The colourless mobile fluid connective tissue drains into the lymphatic 
capillaries from the intercellular spaces. It is formed by squeezing of blood through 
capillaries, within tissues. Its flow is unidirectional i.e., from tissues to heart.
Composition : It is composed of fluid matrix, plasma having only lymph ocytes 
of white blood corpuscles or leucocytes.
Functions : (i) It drains excess of tissue fluid from extra cellular spaces 
back into the blood.
(ii) It contain lymphocytes and antibodies.
(iii) It transport digested fats.
Blood Clotting :   Coagulation of Blood :
Injured Tissue Blood Platelets
Releases Disintegrate
? and release 
?
Thromboplastins Platelet thromboplastin
Ca++ Proteins Ca+ Proteins
?     ?
Thrombokinase
Inactivates heparin and 
catalyses
Ca++
Prothrombin Thrombin
  ?  Catalyses
Fibrinogen
Fibrin
(Fibrin + Blood cells     
Clot or Coagulum)
Page 4


Points To Remember
Blood : A special connective tissue that circulates in principal vascular 
system of man and other vertebrates consisting of fluid matrix, plasma and formed 
elements (Blood = Plasma + All blood cells).
Plasma : (Blood – All blood cells = Plasma) The liquid part of blood which 
is straw coloured, viscous fluid and contains about 90-92% of water and 6-8% 
proteins.
Lymph : A clear yellowish, slightly alkaline, coagulable tissue fluid, 
containing white blood cells (Only lymphocytes), a liquid resembling blood 
plasma.
Serum : Blood plasma from which fibrinogen and other clotting factors 
have been removed. (Plasma– (fibrinogen & other clotting factor) = blood serum.
Heart Beat : The rhythmic contraction and relaxation of the heart, which 
includes one systole (contraction phase) and one diastole (relaxation phase) of 
the heart. Heart beat count of healthy person is 72 times per minute.
Stroke Volume : The volume of blood pumped out by the heart during a 
systole. If is approximately 70 ml.
Cardiac output : The amount of blood pumped by heart per minute is called 
cardiac or heart output. The value of cardiac output of a normal person is about 
72 × 70 = 5040 mL or about 5L per minutes.
Cardiac Cycle : The rhythmic contraction and dilation of different parts of 
heart in one beat.
Systole : Contraction of heart muscles.
Diastole : Relaxation of heart muscles
Name and Number/ Structure Life Span and Function
Percentage Formation
(A) Erythrocytes RBCs Red colour Formed from birth Transport of oxygen
- 4.5 to 5.5 million Circular, biconcave onward by red bone and some amount
per cubic millimetre of denucleated, elastic marrow Life-120 days of carbon dioxide
blood lack of cell organelles excess RBCs are through haemoglobin
like ER, ribosomes, stored in spleen 
mitochondria etc.
(B) Leucocytes Colourless rounded Formed in red bone Acts as soldiers
(WBCs) 5000-8000 or irregular, marrow, Lymph scavenger and some
per cubic mm of nucleated 12 to nodes, spleen and help in healing
blood 20mm wide, life 1-4 thymus
days
(i) Agranulocytes Large rounded Lymph nodes, Non Phagocytic
(a) Lymphocytes 20-45% nucleus, 6-10 mm spleen, thymus red secrete antibodies
of leucocytes bone marrow, life few 
days to months or
even years
(b) Monocytes 6-8% of Largest of all (12-15 Red Bone marrow, phagocytic, very
leucocytes, mm) bean shaped life 10-20 hours motiles engulf
nucleus germs
(ii) Granulocytes 
(a) Eosinophils 2-3% bilobed nucleus, Red Bone marrow, play role in immunity
of leucocytes granules in cytoplasm life 4 to 8 hrs. in non phagocytic
blood
(b) Basophils 0-5% of Three lobed nucleus Red Bone marrow, release heparin and
leucocytes (s-shaped) life 4 to 8 hours in histamine
blood
(c) Neutrophils 60-65% Many lobed nucleus Red Bone marrow, phogocytic, engulf
of leucocytes fine granules life 4 to 8 hours in germ and dead cells
blood
(C) Platelets Colourless, rounded Red Bone marrow help in blood clotting
thrombocytes or oval, or irregular worm out ones
1,50,000-3,50,000 per non-nucleated phagocytized in blood
cubic mm of blood fragments
TYPES OF BLOOD CELLS THEIR NUMBER, STRUCTURE & FUNCTIONS
Biology Class - 11
Blood Pressure—The resistance offered by the lumen of the artery to the 
flow of  Blood.
Hypertension : The condition when blood pressure is higher than normal 
(120/80 mmHg)
Electrocardiograph : (ECG) the machine used to record electrocardiogram.
Electrocardiogram ECG : The print out of pattern of heart beat taken on 
a graph paper from Electrocardiograph. (EGC machine)
Lymph
The colourless mobile fluid connective tissue drains into the lymphatic 
capillaries from the intercellular spaces. It is formed by squeezing of blood through 
capillaries, within tissues. Its flow is unidirectional i.e., from tissues to heart.
Composition : It is composed of fluid matrix, plasma having only lymph ocytes 
of white blood corpuscles or leucocytes.
Functions : (i) It drains excess of tissue fluid from extra cellular spaces 
back into the blood.
(ii) It contain lymphocytes and antibodies.
(iii) It transport digested fats.
Blood Clotting :   Coagulation of Blood :
Injured Tissue Blood Platelets
Releases Disintegrate
? and release 
?
Thromboplastins Platelet thromboplastin
Ca++ Proteins Ca+ Proteins
?     ?
Thrombokinase
Inactivates heparin and 
catalyses
Ca++
Prothrombin Thrombin
  ?  Catalyses
Fibrinogen
Fibrin
(Fibrin + Blood cells     
Clot or Coagulum)
179
Functions of Blood
Transport, of food, respiratory gases (O
2
 and CO
2
), hormones, metabolic 
intermediates, waste products, supply of raw materials, regulation of water balance, 
regulation of pH and body temperature, and provides immunity.
Blood Groups : Based on presence of Antigens and Antibodies in blood.
Blood Antigen (on Anti body : (in Possible recipients Possible donors Remarks
 Group the Surface plasma) having blood group having blood 
of R.B.Cs) group
A A Anti B A, AB O, A —
B B Anti A B, AB O, B, —
AB A and B None AB O, A, B, AB Universal
recipient
O None Anti A and O, A, B, AB O Universal
Anti  B Donor
Rh (Rhesus) Group :
Discovered by Landsteiner and Wiener in 1940 the antigen found on the 
surface of RBCs. The presence of this antigen is termed as Rh-positive (Rh+) and 
its absence as (Rh–). It plays a crucial role in childs birth born out of a marriage 
between Rh– woman and Rh+ man, causing to produce anti Rh antibodies.
?SAN (Sino-artrial node) : A patch of tissues present in the right upper 
corner of the right atrium, acts are pacemaker due to having a unique property 
of self exitation.
?A VN (Atrio Ventricular Node) : A mass of tissues seen in the lower left 
corner of the right atrium close to the atrio-ventricular septum. Fresh wave of 
contraction generated here, passes over both the ventricles simultaneously along 
the bundle of his.
Page 5


Points To Remember
Blood : A special connective tissue that circulates in principal vascular 
system of man and other vertebrates consisting of fluid matrix, plasma and formed 
elements (Blood = Plasma + All blood cells).
Plasma : (Blood – All blood cells = Plasma) The liquid part of blood which 
is straw coloured, viscous fluid and contains about 90-92% of water and 6-8% 
proteins.
Lymph : A clear yellowish, slightly alkaline, coagulable tissue fluid, 
containing white blood cells (Only lymphocytes), a liquid resembling blood 
plasma.
Serum : Blood plasma from which fibrinogen and other clotting factors 
have been removed. (Plasma– (fibrinogen & other clotting factor) = blood serum.
Heart Beat : The rhythmic contraction and relaxation of the heart, which 
includes one systole (contraction phase) and one diastole (relaxation phase) of 
the heart. Heart beat count of healthy person is 72 times per minute.
Stroke Volume : The volume of blood pumped out by the heart during a 
systole. If is approximately 70 ml.
Cardiac output : The amount of blood pumped by heart per minute is called 
cardiac or heart output. The value of cardiac output of a normal person is about 
72 × 70 = 5040 mL or about 5L per minutes.
Cardiac Cycle : The rhythmic contraction and dilation of different parts of 
heart in one beat.
Systole : Contraction of heart muscles.
Diastole : Relaxation of heart muscles
Name and Number/ Structure Life Span and Function
Percentage Formation
(A) Erythrocytes RBCs Red colour Formed from birth Transport of oxygen
- 4.5 to 5.5 million Circular, biconcave onward by red bone and some amount
per cubic millimetre of denucleated, elastic marrow Life-120 days of carbon dioxide
blood lack of cell organelles excess RBCs are through haemoglobin
like ER, ribosomes, stored in spleen 
mitochondria etc.
(B) Leucocytes Colourless rounded Formed in red bone Acts as soldiers
(WBCs) 5000-8000 or irregular, marrow, Lymph scavenger and some
per cubic mm of nucleated 12 to nodes, spleen and help in healing
blood 20mm wide, life 1-4 thymus
days
(i) Agranulocytes Large rounded Lymph nodes, Non Phagocytic
(a) Lymphocytes 20-45% nucleus, 6-10 mm spleen, thymus red secrete antibodies
of leucocytes bone marrow, life few 
days to months or
even years
(b) Monocytes 6-8% of Largest of all (12-15 Red Bone marrow, phagocytic, very
leucocytes, mm) bean shaped life 10-20 hours motiles engulf
nucleus germs
(ii) Granulocytes 
(a) Eosinophils 2-3% bilobed nucleus, Red Bone marrow, play role in immunity
of leucocytes granules in cytoplasm life 4 to 8 hrs. in non phagocytic
blood
(b) Basophils 0-5% of Three lobed nucleus Red Bone marrow, release heparin and
leucocytes (s-shaped) life 4 to 8 hours in histamine
blood
(c) Neutrophils 60-65% Many lobed nucleus Red Bone marrow, phogocytic, engulf
of leucocytes fine granules life 4 to 8 hours in germ and dead cells
blood
(C) Platelets Colourless, rounded Red Bone marrow help in blood clotting
thrombocytes or oval, or irregular worm out ones
1,50,000-3,50,000 per non-nucleated phagocytized in blood
cubic mm of blood fragments
TYPES OF BLOOD CELLS THEIR NUMBER, STRUCTURE & FUNCTIONS
Biology Class - 11
Blood Pressure—The resistance offered by the lumen of the artery to the 
flow of  Blood.
Hypertension : The condition when blood pressure is higher than normal 
(120/80 mmHg)
Electrocardiograph : (ECG) the machine used to record electrocardiogram.
Electrocardiogram ECG : The print out of pattern of heart beat taken on 
a graph paper from Electrocardiograph. (EGC machine)
Lymph
The colourless mobile fluid connective tissue drains into the lymphatic 
capillaries from the intercellular spaces. It is formed by squeezing of blood through 
capillaries, within tissues. Its flow is unidirectional i.e., from tissues to heart.
Composition : It is composed of fluid matrix, plasma having only lymph ocytes 
of white blood corpuscles or leucocytes.
Functions : (i) It drains excess of tissue fluid from extra cellular spaces 
back into the blood.
(ii) It contain lymphocytes and antibodies.
(iii) It transport digested fats.
Blood Clotting :   Coagulation of Blood :
Injured Tissue Blood Platelets
Releases Disintegrate
? and release 
?
Thromboplastins Platelet thromboplastin
Ca++ Proteins Ca+ Proteins
?     ?
Thrombokinase
Inactivates heparin and 
catalyses
Ca++
Prothrombin Thrombin
  ?  Catalyses
Fibrinogen
Fibrin
(Fibrin + Blood cells     
Clot or Coagulum)
179
Functions of Blood
Transport, of food, respiratory gases (O
2
 and CO
2
), hormones, metabolic 
intermediates, waste products, supply of raw materials, regulation of water balance, 
regulation of pH and body temperature, and provides immunity.
Blood Groups : Based on presence of Antigens and Antibodies in blood.
Blood Antigen (on Anti body : (in Possible recipients Possible donors Remarks
 Group the Surface plasma) having blood group having blood 
of R.B.Cs) group
A A Anti B A, AB O, A —
B B Anti A B, AB O, B, —
AB A and B None AB O, A, B, AB Universal
recipient
O None Anti A and O, A, B, AB O Universal
Anti  B Donor
Rh (Rhesus) Group :
Discovered by Landsteiner and Wiener in 1940 the antigen found on the 
surface of RBCs. The presence of this antigen is termed as Rh-positive (Rh+) and 
its absence as (Rh–). It plays a crucial role in childs birth born out of a marriage 
between Rh– woman and Rh+ man, causing to produce anti Rh antibodies.
?SAN (Sino-artrial node) : A patch of tissues present in the right upper 
corner of the right atrium, acts are pacemaker due to having a unique property 
of self exitation.
?A VN (Atrio Ventricular Node) : A mass of tissues seen in the lower left 
corner of the right atrium close to the atrio-ventricular septum. Fresh wave of 
contraction generated here, passes over both the ventricles simultaneously along 
the bundle of his.
Human Heart
Human Heart
? It is the mesodermally derived organ situated in thoracic cavity in between
the two lungs. Protected by a double membrane covering called Pericardium.
? Four chambers–two (left and right) atria, and two ventricels (left and right)
? Inner-artrial septum separates the two atria and inter ventricular septum
separates the two ventricles, while the atria and ventricles are separated by
atrioventricular septum.
? The valves between right atrium and right ventricle is tricuspid while between
left atrium and ventricle is bicuspid or mitral value.
? The opening of the right ventricle into the pulmonary artery and the opening
of left ventricle in to aorta are guarded by semilunar values.
? The valves allow the flow of blood only in one direction, i.e., from atria to
ventricles and from ventricles to pulmonary artery or aorta.
Heart V alves
Tricuspid Valve : The valves formed of three muscular flaps or cups, which 
guard the opening between the right atrium and the right ventricle.
Bicuspid Valve (Mitral Valve) : The valves which guard the opening 
between the left atrium and  the left ventricle, made up of two flaps.