Download Circulation Final

6. CIRCULATION
Introduction
1)
Origin of the Circulatory System :
Whole circulatory system: Mesoderm of embryo
Except inner lining of blood vessels and heart: Endodermal origin
2)
Evolution of Circulatory System in Animal Kingdom :
SR. NO.
Phylum
1
Protozoa
2
Porifera
3
Coelentrata
4
Platyhelminthes
5
Aschehelmenthes
6
7
8
9
Annelida
Arthropoda
Mollusca
Ecchinodermata
10
Hemichordata
Type of Circulation
Circulatory Fluid
Intracellular circulation
Through cyclosis
Extracellular circulation
Extra-organismic circulation
Extracellular circulation
Extra-organismic circulation
Gastrovascular system
Parenchymal circulation
Cytoplasm
Water circulation
Water circulation
Extracellular circulation
Intra-organismic circulation
Pseudocoelomic circulation
Closed Circulation
Open Circulation
Open circulation except cephalopods
Watervascular system
Ambulacral system
Closed circulation
No fluid
Diffusion
Pseudocoelomic fluid
Blood
Haemolymph
Haemolymph / Blood
Water circulation
Blood
3)
Medium of Transportation :
Two Types :
i)
Water Circulation System :
Water is the medium of transportation.
E.g. sponges(water canal system), Hydra (gastrovascularsystem), star fish (ambulacral system)
ii)
Blood Vascular System :
Blood is the medium of transportation in association with pumping organ (heart)
E.g. vertebrates, annelids
4)
Difference between the open and the closed circulatory system :
Open Circulatory System
Here the circulating fluid moves in an open space.
The open space is called sinus/lacuna/haemocoel.
The fluid is called haemolymph.
Haemolymph moves under low pressure.
Haemolymph comes in direct contact with cells.
Circulation
Closed Circulatory System
Here the circulating fluid moves within a closed space
The closed space is called blood vessels.
The fluid is called blood.
Blood moves under high pressure.
Blooddoes not come in direct contact with cells.
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Open Circulatory System
There are no capillaries.
There is no true heart.
This system is less efficient.
Insects can get by with this type system because they
have numerous openings in their bodies (spiracles)
that allow theblood to come into contact with air
E.g. arthropods and molluscs
1)
Closed Circulatory System
There are arteries, veins and capillaries.
There is a true heart.
This system is more efficient.
Found in higher animals.
E.g. annelids (earthworm), some molluscs (such as squid,
octopus) and all vertebrates
BLOOD
R.B.C.s. :
i)
R.B.C.s do not have nucleus, mitochondria, golgi apparatus, centriole, lysosomes.
ii)
They contain 2, 3 DPG.
iii)
All mammals have enucleated RBCs except camels, lamas and sloth.
iv)
RBCs are counted on a haemocytometer, whereas haemoglobin estimation is done on a haemometer.
v)
Composition : 60% water, 40% solids – out of which 29% - haemoglobin
vi)
Haemoglobin is Fe++ based, present in most vertebrates, in earthworm it is directly dissolved in plasma
vii)
Haemocyanin is Cu++ based, present in - molluscs & crustaceans
viii) Haemoglobin :
a)
1 RBC contains 280 million molecules of haemoglobin.
b)
1 haemoglobin is made up of 4 parts of iron containing haem and 4 chains of non iron part called globulin which
has 2 alpha and 2 beta chains.
c)
1 molecule of haemoglobin can transport 4 molecules of O2.
d)
Haemoglobin has maximum affinity for CO followed by CO2andO2.
e)
When haemoglobin combines with CO it forms carboxyhaemoglobin. With CO2 it forms carbaminohaemoglobin
and with O2 it forms oxyhaemoglobin.
f)
Haemoglobin values for males – 14 – 18 gms/dL
for females – 11.5 – 16.5 gms/dL
for infants – 23 gms/dL
g)
Foetuses contain foetal type of haemoglobin which is made up of 2 alpha and 2 gamma chains. This type of
haemoglobin works at 50% efficiency.
h)
Thalassaemic patients have haemoglobin which contains 2 alpha and 2 delta chains.
ix)
Breakdown of haemoglobin:
a)
Haemoglobin is broken down by the liver and spleen. Spleen is called the graveyard of RBCs.
b)
Haemoglobin is first separated into its two main components – haem and globulin.
c)
The globulin chains which are detached are sent to plasma for re-use.
d)
The iron from haem is first extracted to be stored in the liver in the form of ferritin.
e)
The remaining haem is broken down by multiple chemical reactions to form biliverdin and bilirubin which is
finally given to the small intestine for removal.
f)
The normal count of bilirubin is approx. 0.5 mg/dL.
g)
If this value exceeds 3 times its normal value it results in yellowishness of skin called jaundice.
h)
Yellow discolouration of sclera is called icterus.
RBCs also contain enzyme carbonic anhydrase which catalyses the reaction between CO2 and H2O to form carbonic
–
–
acid. This carbonic acid splits into H+ and HCO3 . The HCO3 then combine with Na+ or K+ ions to form carbonates of
sodium or potassium which act as buffers.
Circulation
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x)
Diseases of RBC
i)
Decrease in RBC count - erythropenia
ii)
Increase in RBC count - polycythemia
iii)
Lack of oxygen carrying capacity of blood - anaemia
iv)
Types of anaemia
Sr. No.
1)
2)
3)
4)
5)
2)
Type of Anaemia
Iron Deficiency Anaemia (IDA)
Megaloblastic Anaemia
Pernicious Anaemia
Haemolytic Anaemia
Sickle Cell Anaemia
Cause
lack of iron in diet/ decreased absorption of iron in the body
Deficiency of vit. B12 & Folic acid
Deficiency of folic acid
due to excess breakdown of RBCs
defect in beta- globulin chain where on the 6th position glutamic acid is
replaced by valine
Platelets :
i)
Function of platelets is clotting of blood.
ii)
Blood has natural anticoagulants called heparin and antithrombin
iii)
Vitamin K is required for the formation of prothrombin.
iv)
Ca++ is required for clotting process.
v)
Artificial anticoagulants contain oxalates, citrates and bicarbonates and are used to store blood in a blood bank.
vi)
A natural anticoagulant called hirudin is derived from the saliva of leeches.
vii)
Diseases of platelets:
a)
Decrease in platelet count – Thrombocytopenia
b)
Increase in platelet count – Thrombocytosis
viii) Disorders of clotting :
ix)
Deficiency of clotting factors leads to clotting disorders.
a)
Deficiency of factor :
VIII – Haemophilia A
IX – Haemophilia B
XI – Haemophilia C
b)
Haemophilia is also called as Bleeder’s disease/ Royal disease.
x)
Thrombosis- Formation of a clot (thrombus) inside a blood vessel, obstructing the flow of blood
xi)
Embolism- occurs when an object (usually a blood clot) migrates from one part of the body (through circulation)
andcauses a blockage (occlusion) of a blood vessel in another part of the body.
Blood Vessels
1)
Blood Vessels :
i)
Blood vessels of the blood vessels – Vasa vasorum.
ii)
Arteries – Their tunica media may contain only scattered modified smooth muscle cells called pericytes.
iii)
Arterioles – can control blood flow to the capillary beds they supply; blood flow changes from pulsatile to smooth.
Arterioles finally break up into blood capillaries.
They are more susceptible to injury & diseases e.g. Atherosclerosis.
iv)
Capillaries :
Discovered by Marcello Malpighi, 1661
Blood flow is at its slowest through the capillaries because they are the narrowest vessels which means they have the
greatest friction which restricts blood flow.
This slow velocity aids the exchange of materials.
v)
Types of capillaries
a)
Continuous capillaries
b)
Fenestrated capillaries
c)
Discontinuous capillaries
Circulation
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a)
Continuous capillaries :
b)
1)
Most common type
2)
Surrounded by a basement membrane
3)
Have tight occluding junctions and gap junctions between cells;
4)
No pores or spaces between cells in walls.
5)
Abundant in brain, parenchyma, connective tissues, skeletal muscle.
Fenestrated capillaries :
1)
2)
3)
4)
Also called perforated capillaries
Pores penetrate the endothelial cells
Found in tissues where rapid exchange of substances occurs
Present in villi of the intestinal wall, endocrine tissues, renal glomerulus & around renal tubules, choroid
plexus, mucosa of gastrointestinal tract, ciliary body of eye etc.
Circulation
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c)
Discontinuous capillaries :
1)
2)
3)
4)
5)
6)
7)
8)
2)
Also called sinusoidal capillaries
Form incomplete endothelial barrier between vascular channel and organ parenchyma
highly convoluted and with enlarged diameter (30-40 um)
open spaces present between endothelial cells
in some, many small multiple fenestrations penetrate the endothelial cells
phagocytic cells present in and around the endothelial layer
endothelium lacks a continuous basal lamina
abundant in liver sinusoids (Kupffer cells) and hematopoietic organs such as bone marrow and spleen.
Portal System :
i)
Portal vein – It collects blood from one organ by a set of capillaries and distributes that blood, into a second organ
through another set of capillaries instead of sending the blood directly into the vena cava or the heart.
ii)
Types of portal system :
a)
Hepatic portal system
b)
Renal portal system
c)
Hypophysial portal system
Hepatic Portal System
Circulation
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i)
ii)
iii)
iv)
v)
vi)
Occurs in all vertebrates
Brings venous blood directly from digestive tract, spleen, pancreas and gall bladder to liver
Pours blood from digestive system into the liver
This blood is collected by hepatic veins and poured into post caval to be returned to the heart
This system functions as a short circuit for:
a)
Removal of glucose, amino acids and other nutrients
b)
Deamination of extra amino acids and conversion of harmful ammonia into urea
c)
Separation of chemical and their detoxification
d)
Direct pouring of liver products into venous blood
Portal vein is about 8 cm long
Renal Portal System
i)
ii)
It consists of renal portal veins that brings blood from posterior part of the body directly into kidneys for removal of
waste products
It is well developed in fishes and amphibians, reduced in reptiles and birds and absent in mammals
Hypophysial Portal System
Circulation
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i)
ii)
iii)
iv)
v)
vi)
vii)
It is a portal system formed by a vein from hypothalamus which breaks up into capillaries in hypophysis or pituitary
gland.
Formed by union of capillaries and venules in hypothalamus
Portal vein enters anterior lobe of pituitary gland or adenohypophysis where it breaks up into capillaries
Hypophysial portal system is a short circuit arrangement
Hypothalamus produces a number of hormones for controlling endocrine activity of adenohypophysis
They are pored into blood in hypothalamus
The same is directly drained by hypophysial portal vein into adenohypophysis
3)
Names of some important blood vessels :
i)
Radial : artery of the forearm.
ii)
Brachial : artery of the arm.
iii)
Femoral : vessel carrying blood to the thigh.
iv)
Common carotid : vessel carrying blood to the neck.
v)
External carotid : neck vessel carrying blood to the face.
vi)
Internal carotid : neck vessel carrying blood to the brain.
vii)
Coronary artery : blood vessel of the heart
viii) Thoracic aorta : main artery of the thorax.
ix)
Renal : vessel carrying blood to the kidneys.
4)
Diseases of Blood vessels :
i)
Arteriosclerosis :
Stiffening of arteries due to loss of elasticity
ii)
Atherosclerosis :
Deposition of cholesterol or nicotine within the blood vessel leading to occlusion of the blood vessel.
iii)
Aneurysm :
a)
Localized bulge of a blood vessel caused by disease or weakening of the vessel wall.
b)
Most commonly occur in arteries at the base of the brain and in the aorta.
c)
Can burst and lead to death at any time.
iv)
Varicose veins :
Dilated and tortuous veins causing pooling of blood. Caused due to defective venous valves.
v)
Haemorrhage :
a)
Haemorrhage is the medical term for bleeding - the loss of blood from the body
b)
Haemorrhage generally becomes dangerous, or even fatal, when it causes hypovolemia (low blood volume) or
c)
Hypotension (low blood pressure)
vi)
Hematoma :
Collection of blood due to internal bleeding (bruise)
HEART
1)
Human Heart :
i)
Human heart
The human heart beats appox. 72 times per minute, 100,0000 times per day.
a)
External structure :
1)
Situated in between 2 lungs in a space called the mediastinum.
2)
The apex of the heart is made up by the left ventricle.
b)
Internal structure :
1)
The inner wall of atria show a series of transverse muscular ridges: musculi pectinati which give the
appearance of the teeth of a comb (combed muscles).
2)
Valves :
i)
Opening of Superior Vena Cava – Haversian valve
ii)
Opening of Inferior Vena Cava – Eustachian valve
iii)
Opening of Coronary Sinus – Thebesian valve
Circulation
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c)
Histology of the heart :
The heart wall made up of 3 layers:
1)
Epicardium: outermost; mesodermal in origin; made of simple squamous epithelium
2)
Myocardium: middle; thickest, mesodermal; made of cardiac muscles which are striated but involuntary
3)
Endocardium: innermost; endodermal in origin; made of simple squamous epithelium
Distribution of blood to different organs :
Parts
Percentage of blood received
Heart muscles
Brain
Digestive tract
Kidneys
Other organs
2)
10%
15%
25%
20%
30%
Evolution of the heart in vertebrates :
Pisces
Amphibia
2 chambered heart 3 chambered heart
Single circulation Double circulation
3)
Reptilia
incompletely 4 chambered
heart(except crocodiles)
Double circulation
Mammalia
4 chambered heart
Double circulation
Neurogenic v/s Myogenic heart :
Neurogenic heart
Myogenic heart
Impulse of heart beat comes from outside heart.
Impulse is generated by nervous system
Nerve fibres are spread over the heart to bringabout
contraction and relaxation
Heart will stop beating if removed from the body.
The impulse of heart beat develops within the heart itself.
Impulse is generated by a special muscular tissue
There are special conducting muscle fibres for spreading the
impulse
If the heart is removed from the body It will continue to beat for
some time, if it is suppliedwith proper nourishment and favourable
conditions.
e.g. heart of vertebrates
e.g. heart of molluscs
4)
Aves
4 chambered heart
Double circulation
Heart Rate:
In mammals, smaller animals have higher heart beat
i)
Rabbit: 200/min
ii)
Sparrow: 500/min
iii)
Canary: 1000/min
iv)
Elephant: 28/min
v)
Frog: 64/min
vi)
Rat: 300/min
vii)
Shrew: 800/min (maximum)
viii) Blue whale: 25/min (minimum)
Circulation
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Causes of tachycardia & bradycardia :
Tachycardia
Heart rate more than 90 per minute for an average adult.
Increase in blood pressure in the vena cava
Increase in blood CO2 concentration
Decrease in blood O2 concentration
Decrease in blood pH
Increase in body temperature (core temperature)
Increase in hormone adrenaline
Increase in the nervous input from pain receptors
Bradycardia
Heart rate less than 60 per minute for an average adult.
Increase in blood pressure in aorta and large arteries
Decrease in blood CO2 concentration
Increase in blood O2 concentration
Increase in blood pH
Decrease in body temperature (core temperature)
Decrease in adrenaline/ Increase in acetylcholine
Parasympathetic stimulation
The ratio of heart rate to respiratory rate in an average adult under normal circumstances is 4 : 1
5)
6)
Heart Sounds :
i)
Heart beats are listened with the help of an instrument called Stethoscope.
ii)
Stethoscope invented by Laennec.
iii)
The study of heart sounds by marking them on a graph: Phonocardiography
iv)
Heart Sounds
a)
Ist Sound :
1)
This is a contraction sound which denotes the beginning of ventricle contraction
2)
Arises due to closing of the tricuspid and bicuspid valve.
3)
Weak and appears in the form of “Lubb”
4)
Duration of 0.15 second and a frequency of 25-45 Hz
b)
IInd Sound :
1)
This is a diastolic sound which denotes the beginning of ventricular diastole
2)
Arises due to the closing of the semi-lunar valves of the two arches
3)
Heard in the form of “Dup”
4)
Duration of 0.12 seconds with a frequency of 50 Hz
v)
Heart sounds give valuable information about working of valves.
vi)
Any damage to these valves effects the quality of sound.
vii)
The abnormal heart sound due to damaged valve is called a Heart murmur.
Diseases of the heart :
i)
Myocardial infarction :
a)
Also called as Heart attack.
b)
Usually due to a blockage in the coronary arterydue to a plaque (fat, cholesterol, and calcium)
c)
Leads to insufficient blood supply to a part of cardiac muscle.
d)
Initially there is low oxygen supply to cardiac muscles called Myocardial ischaemia.
e)
Later on it leads to the death of cardiac muscles called myocardial infarction.
f)
Signs of heart attack :
1)
chest pain
2)
pain or discomfort in the upper body (arms, back, neck, jaws or stomach)
3)
shortness of breath (usually occurs at the same time as chest pain)
4)
cold sweat
5)
nausea or vomiting
6)
light headedness
ii)
Angina pectoris
a)
Sclerosis of the coronary arteries can cause pain in the chest
b)
This anginal pain usually starts in the centre of the chest and spreads down the left arm
c)
The chest pain may be associated with restlessness, fear or anxiety, a pale skin, profuse sweating and vomiting
(all because of increase adrenergic discharge)
d)
The pain lasts for only a few moments
Circulation
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iii)
iv)
v)
vi)
vii)
viii)
Heart block
a)
Condition in which the SA (sinus node) is normal but the impulses are interrupted at any point along the
conducting system of the heart
b)
Thus impulses do not follow the normal conduction pathway
c)
Two common types of heart block:
d)
AV block : occurs at the AV node (atrioventricular node); impulses from the SA node do not reach the AV node.
e)
Bundle branch block: involves one of the branches of the bundle of His
Cardiac arrest
It is the complete stoppage of the heart beat (sudden and complete loss of cardiac-function).
Heart failure
It is the state of heart when it does not pump blood effectively enough to meet the need of the body.
Cardiomegaly :
Enlargement of the heart.
Rheumatic heart disease
a)
The patient may have an acute rheumatic fever, joint pains and infection of throat
b)
Rheumatic fever may cause permanent damage of one or more valves (mitral or aortic semilunar valves),
pericarditis and myocarditis.
Congenital heart diseases
a)
Defects or diseases of theheart from the birth: congenital heart diseases
b)
Occur due to some error in the development of the heart
c)
Some of these defects may be due to an infectious disease like rubella (German measles) in the mother or
administration of some harmful drugs during first three months of pregnancy
d)
A small number of cases of congenital heart diseases are associated with chromosomal abnormalities.
7)
Laws related to the cardiovascular system :
i)
Frank - Starling Law :
The law states that: “ The more the cardiac muscle is stretched within its physiological limits, the more forcibly it will contract’’.
ii)
Marey’s law of heart :
There is an inverse relationship between rate of heart beat and blood pressure.
8)
ECG :
i)
Einthoven invented ECG for recording heart conditions. He is known as the father of ECG.
ii)
Abnormalities of ECG.
a)
Enlargement of the P wave indicates enlargement of the atria
b)
Long P-R interval – seen in atherosclerotic heart disease and rheumatic fever.This is due to the inflammation of
atria and AV node
c)
Enlarged Q and R waves indicate a myocardial infarction (heart attack).
d)
S-T segment elevation - in acute myocardial infarction and depressed when the heart muscle receives insufficient
oxygen.
e)
Flat T wave - when the heart muscles receive insufficient oxygen as in atherosclerotic heart disease
f)
Elevated T wave - the body’s potassium level is increased
9)
Foetal circulation :
i)
Foetus depends completely on the mother and her placenta
ii)
Foetal circulation differs mainly from the adult one by the presence of 3 major vascular shunts:
a)
Ductus venosus: between the umbilical vein and inferior vena cava
b)
Foramen ovale: between the right and left atrium (i.e. opening in interatrial septum)
c)
Ductus arteriosus: between the pulmonary artery and descending (dorsal) aorta
iii)
Rationale of these shunts is to divert the oxygenated blood from the less functioning organs as lungs, liver, kidney and
intestine as placenta carries their functions, to the brain, heart and other parts of the body
iv)
Shunts are sealed after birth.
v)
If remains opens then it is known as ‘hole’ in the heart which is closed by surgery or giving medicine
vi)
‘Blue baby‘: name given to an abnormal human baby who has a hole in the ventricular septum so that oxygenated and
less oxygenated blood mix
Circulation
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LYMPHATIC SYSTEM
1)
Cysterna Chyli: expanded abdominal portion of the thoracic duct; this is where fat enter the lymphatic system.
2)
Spleen
i)
Located in the superior, posterior, left abdominal cavity
ii)
Contains largest collection of lymphoid tissue in the body
iii)
Performs the same function for blood that lymph nodes perform for lymph; the spleen filters the blood.
iv)
It contains the red pulp and white pulp.
v)
Red pulp :
a)
area of the spleen that contains large numbers of RBCs
b)
structural framework of the red pulp consists of a network of reticular fibres
c)
rich in macrophages
d)
mainly concerned with disposing of worn out red blood cells and blood borne pathogens
vi)
White pulp :
a)
area of the spleen that resembles lymphoid nodules
b)
composed mostly of lymphocytes suspended on reticular fibres
c)
involved with the immune functions of the spleen
vii)
Functions :
a)
Destruction of worn-out red corpuscles: worn-out RBCs are phagocytized by the free and fixed macrophages
present in the spleen; often described as the “graveyard” or “slaughter house” of the worn-out erythrocytes.
b)
Reservoir for red corpuscles: When the animal is at rest and needs less oxygen due to slow metabolism, some
red corpuscles are withdrawn from circulation and stored in the spleen. During active life, when the animal
requires more oxygen, also in case of haemorrhage (blood loss in injury), stored red corpuscles are released into
the blood stream.
c)
Formation of agranulocytes: Lymphocytes & monocytes are produced in the bone marrow and spleen besides
thymus and lymph nodes.
d)
Production of antibodies: Plasma cells present in the spleen produce antibodies, the protective proteins that
provide immunity
e)
Storage of iron: Iron freed from the haemoglobin of the worn-out RBCs is stored in the macrophages till it is
needed for reuse in the synthesis of fresh haemoglobin
f)
Erythropoiesis : In the embryo, spleen produces new RBCs
g)
Disposal of foreign elements: macrophages of the spleen engulf and destroy foreign germs and other substances
entering the blood
Circulation
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EXERCISE - 1
1.
In open vascular system, the circulating fluid is called
(a)
perilymph
(b)
lymphatic fluid
(c)
haemolymph
(d)
blood
2.
Which one of the following has an open circulatory
system ?
(a)
Pheretima
(b)
Periplaneta
(c)
Hirudinaria
(d)
Octopus
3.
Which of the following has a closed type of circulatory
system?
(a)
Cockroach
(b)
Fish
(c)
Scorpion
(d)
Limulus
4.
The circulatory system of cockroach is
(a)
Closed
(b)
Lacunar
(c)
Simple
(d)
Complex
5.
6.
12.
Which two of the following changes (i-iv) usually tend
to occur in the plain dwellers when they move to high
altitudes (3, 500 m or more) ?
(i)
Increase in red blood cell size
(ii)
Increase in red blood cell production
(iii) Increase in breathing rate
(iv) Increase in thrombocyte count
(a)
(ii) and (iii)
(b)
(iii) and (iv)
(c)
(i) and (iv)
(d)
(i) and (ii)
13.
RBCs do not occur in
(a)
frog
(c)
camel
(b)
(d)
cow
cockroach
14.
Circulatory system of earthworm is
(a)
open
(b)
closed
(c)
both above
(d)
open anteriorly
Haemoglobin is
(a)
an oxygen carrier in human blood
(b)
a protein used as food supplement
(c)
an oxygen scavenger in root nodules
(d)
a plant protein with high lysine content
15.
Serum is
(a)
Blood without fibrinogen
(b)
Lymph without corpuscles
(c)
Blood without corpuscles and fibrinogen
(d)
Lymph
Haemoglobin molecule is made up of
(a)
one a -chain and one ß - chains
(b)
two a -chains and two ß - chains
(c)
two a -chains and one ß - chain
(d)
one a -chain and two ß - chains
16.
Carbon monoxide is a more harmful pollutant because it
(a)
has more affinity for haemoglobin
(b)
reacts quickly with UV radiations
(c)
has less affinity for Hb
(d)
cannot compete with oxygen
17.
Carbonic anhydrase occurs in
(a)
lymphocytes
(b)
(c)
RBC
(d)
7.
Which is the principal cation in the plasma of the blood ?
(a)
Magnesium
(b)
Sodium
(c)
Potassium
(d)
Calcium
8.
The pH of blood is
(a)
between 7-8
(c)
between 12-14
(b)
(d)
between 2 - 4
between 2 - 5
blood plasma
leucocytes
9.
Primary blood cells are formed in
(a)
plasma
(b)
bone marrow
(c)
liver
(d)
spleen
18.
Sickle cell anaemia is characterised by
(a)
leukemia
(b)
polycythemia
(c)
mental retardation (d)
haemolytic anaemia
10.
Life span of RBCs is
(a)
50 days
(c)
120 days
19.
Sickle cell anaemia is due to
(a)
change of amino acid in a -chain of haemoglobin
(b)
change of amino acid in ß -chain of haemoglobin
(c)
change of amino acid in both a and ß chains of or
ß -chain of haemoglobin
(d)
change of amino acid in either a or ß -chain of
haemoglobin
11.
(b)
(d)
70 days
220 days
The number of erythrocytes in human are _________per
mm3 of blood
(a)
600000
(b)
400000
(c)
5000000
(d)
550000
Circulation
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Which of the following is absent in an RBC
(a)
lysosomes
(b)
nucleus
(c)
mitochondria
(d)
All of the above
(b)
21.
Cells formed in bone marrow include
(a)
RBC
(b)
RBC and leucocytes
(c)
leucocytes
(d)
lymphocytes
(d)
22.
The granulatory white blood corpuscles are
(a)
basophils, eosinophils and neutrophis
(b)
basophils and monocytes
(c)
eosinophis and lymphocytes
(d)
lymphocytes and monocytes
20.
23.
24.
25.
26.
27.
Agranulocytes are
(a)
eosinophis
(c)
basophis
(c)
A - Eosinophil, B - Lymphocyte, C - Neutrophil,
D - Monocyte
A - Erythrocyte, B - Basophil, C - Neutrophil,
D - Lympnocyte
A - Eosinophil, B - Monocyte, C - Neutrophil,
D - Lymphocyte
28.
Which one engulfs pathogens rapidly?
(a)
Acidophils
(b)
Monocytes
(c)
Basophils
(d)
Neutrophils
29.
Immunoglobulins are producted by
(a)
lymphocytes
(b)
spleen
(c)
leucocytes
(d)
monocytes
(b)
(d)
neutrophils
monocytes
30.
Which of the following corpuscles is the scavenger WBC
(a)
Eosinophis
(b)
Monocytes
(c)
Neutrophils
(d)
Lymphocytes
Granules are not present in
(a)
lymphocytes
(b)
(c)
basophils
(d)
neutrophils
eosinophils
31.
Passage of WBCs out of blood capillaries to the site of
injury is known as
(a)
haemopoesis
(b)
haemolysis
(c)
phagocytosis
(d)
diapedesis
32.
Which of the following represent the correct sequence
of events for defence by leucocytes?
(a)
Inflammation, diapedesis, chemotaxis,
phagocytosis, digestion
(b)
Chemotaxis, inflammation, phagocytosis,
digestion diapedesis
(c)
Diapedesis, digestion, inflammation,
phagocytosis, chemotaxis
(d)
Inflammation, chemotaxis, diapedesis,
phagocytosis, digestion
33.
The blood cancer is known as
(a)
leukaemia
(b)
(c)
haemolysis
(d)
The most abundant granulocytes in human blood are
(a)
basophis
(b)
eosinophis
(c)
neutrophils
(d)
monocytes
Match the types of WBC listed under Column-I with the
shape of nucleus given under Column-II and select the
correct option from codes given below
Column-I
Column-II
(A) Neutrophils
(i)
Kidney-shaped
(B)
Eosinophils
(ii)
S-shaped
(C)
Basophils
(iii) 3 to 5 lobes
(D)
Monocytes
(iv) 2 lobes
(v)
Disc-shaped
(a)
A - (iii), B - (v), C - (i), D - (ii)
(b)
A - (v), B - (iii), C - (i), D - (iv)
(C)
A - (ii), B - (i), C - (v), D - (iii)
(d)
A - (iii), B - (iv), C - (ii), D - (i)
34.
In mammals, histamine is secreted by
(a)
fibroblasts
(b)
histocytes
(c)
lymphocytes
(d)
mast cells
35.
Megakaryocytes give rise to
(a)
erythrocytes
(b)
(c)
agranulocytes
(d)
Study the given figure and identify the cells labelled as
A, B, C and D
36.
(a)
Circulation
A - Eosinophil, B - Erythrocyte, C - Neutrophil,
D - Basophil
thrombosis
haemophilia
granulocytes
thrombocytes
Which are not true cells in the blood ?
(a)
Platelets
(b)
Monocytes
(c)
Neutrophils
(d)
Basophils
..141..
37.
The number of platelets in human are ___ per mm3 of
blood
(a)
5 million
(b)
10 lakh
(c)
2.5 lakhs
(d)
2.5 millions
38.
Thrombocytopenic purpura is a haemorrhagic disorder.
This is because of
(a)
very high platelet count
(b)
very low platelet count
(c)
low concentration of fibrinogen
(d)
absence of vitamin-K
39.
Blood clotting is prevented by the presence of
(a)
Vitamin K
(b)
Calcium ions
(c)
Heparin
(d)
Thrombin
40.
During the process of blood coagulation vitamin K helps
in the
(a)
formation of thromboplastin
(b)
formation of prothrombin
(c)
conversion of prothrombin to thrombin
(d)
conversion of fibrinogen to fibrin
41.
Coagulation of blood in blood vessels in living body is
initiated by
(a)
prothrombin
(b)
thromboplastin
(c)
prothrombin and calcium together
(d)
plasminogen and calcium together
42.
Removal of calcium from freshly collected blood would
(a)
cause delayed clotting
(b)
prevent clotting
(c)
cause immediate clotting
(d)
prevent destruction of haemoglobin
43.
Haemophilia is
(a)
royal disease
(b)
faulty blood clotting
(c)
Both (a) and (b)
(d)
mosquito having haemocoel
44.
45.
Which of the following acts as ‘middle man of the body’?
(a)
Plasma
(b)
Lymph
(c)
RBCs
(d)
WBCs
The lymph serves to
(a)
transport oxygen to the brain
(b)
transport carbon dioxide to the lungs
(c)
return the interstitial fluid to the blood
(d)
return the WBCs and RBCs to the lymph nodes
46.
Which of the following statements is true for lymph?
(a)
WBCs and serum
(b)
All components of blood except RBCs Platelets
and some proteins
(c)
RBCs, WBCs and plasma
(d)
RBCs, proteins and platelets
47.
The difference between blood and lymph is
(a)
blood has RBCs and WBCs, while lymph has no
cells
(b)
blood has RBCs and WBCs, while lymph has only
WBCs
(c)
blood has WBCs, while lymph has RBCs
(d)
blood has dissolve salt, while lymph has no cells
48.
Which of the following is not main function of lymph
glands ?
(a)
Forming WBC
(b)
Forming antibodies
(c)
Forming RBC
(d)
Destroying bacteria
49.
Lymphoid tissue is found in
(a)
thymus
(b)
(c)
lymph nodes
(d)
tonsils
all of these
Spleen is _____ organ is adults
(a)
haemopoietic
(b)
(c)
reproductive
(d)
lymphoid
celluloid
50.
51.
Which is correct for artery?
(a)
Thick-walled in which blood flows at high
pressure
(b)
Thin-walled and blood flow with low pressure
(c)
Thick-walled and blood flow with low pressure
(d)
None of the above
52.
Carotid artery supplies oxygenated blood to
(a)
lungs
(b)
intestine
(c)
brain
(d)
None of these
53.
Pulse beat is measured from
(a)
arteries
(b)
(c)
capillaries
(d)
veins
nerves
54.
Arteries carry oxygenated blood except-artery
(a)
pulmonary
(b)
cardiac
(c)
hepatic
(d)
systemic
55.
The thickening of walls of arteries is called
(a)
arthritis
(b)
atherosclerosis
(c)
anaeurysm
(d)
Both (a) and (c)
Circulation
..142..
56.
57.
A vein possesses a large lumen because
(a)
tunica media and tunica externa form a single coat
(b)
tunica interna and tunica media form a single coat
(c)
tunica interna, tunica media and tunica externa
are thin
(d)
tunica media is a thin coat
59.
60.
61.
Maximum surface area of circulating system is seen in
(a)
heart
(b)
capillaries
(c)
arterioles
(d)
veins
64.
Which of the following portal systems are present in
humans
(a)
hepatic portal system
(b)
hypophyseal portal system
(c)
renal portal system
(d)
both a and b
65.
A portal system is one in which
(a)
a vein starts from an organ and ends up in the
heart
(b)
an artery breaks up in an organ and restarts by
the union of its capillaries
(c)
the blood from the gut is brought into kidney
before it is poured into post caval
(d)
a vein breaks up in an organ into capillaries and
restarts by their union as new vein from the same
organ.
66.
Which one of the following vein breaks up into capillaries ?
(a)
Renal vein
(b)
Hepatic portal vein
(c)
Pelvic vein
(d)
Pulmonary vein
67.
Which of the following carries blood rich in food materials,
such as glucose and amino acids, from intestine to liver ?
(a)
dorsal aorta
(b)
mesentric artery
(c)
renal portal vein
(d)
hepatic portal vein
68.
Which of the following vein has least amount of urea ?
(a)
Pulmonary vein
(b)
Hepatic portal vein
(c)
Hepatic vein
(d)
Renal vein
69.
Blood pressure is defined as the force with which blood
(a)
pushes against the wall of the blood vessels
(b)
is pushed to the legs
(c)
comes out of the atrium
(d)
comes out of the ventricle
70.
Blood pressure is measured by
(a)
Sphygmomanometer (b)
(c)
Electrocardiogram (d)
Given below are the figures of blood vessels. Identify
them and select the correct option
(a)
(b)
(c)
(d)
58.
63.
A
Capillary
Artery
Vein
Vein
B
Vein
Capillary
Capillary
Artery
C
Artery
Vein
Artery
Capillary
In veins, valves are present to check backward flow of
blood flowing at
(a)
high pressure
(b)
low pressure
(c)
atmospheric pressure
(d)
all of these
One of the following blood vessel is with valves
(a)
Artery
(b)
Pulmonary artery
(c)
Vein
(d)
Aorta
Which of the following has no muscular wall?
(a)
Artery
(b)
Vein
(c)
Arteriole
(d)
Capillary
Wall of blood capillary is formed of
(a)
haemocytes
(b)
parietal cells
(c)
endothelial cells
(d)
oxyntic cells
71.
62.
Maximum amount of oxygen is lost from the blood in the
(a)
capillaries surrounding the tissue cells
(b)
arteries of the body
(c)
capillaries surrounding the alveoli
(d)
left auricle of the heart
Circulation
Stethosecope
Phonocardigram
An adult human with average health has systolic and
diastolic pressure as
(a)
80 mm Hg and 80 mm Hg
(b)
70 mm Hg and 120 mm Hg
(c)
120 mm Hg and 80 mm Hg
(d)
50 mm Hg and 80 mm Hg
..143..
72.
Pulse pressure of a normal adult is
(a)
80 mm Hg
(b)
40 mm Hg
(c)
200 mm Hg
(d)
120 mm Hg
73.
Manifestation of increase in the blood pressure of a
person is called
(a)
hypertension
(b)
artherosclerosis
(c)
arteriosc lerosis
(d)
None of these
74.
With advancing age, a person is likely to suffer from
hypertension because
(a)
arteries lose elasticity
(b)
adequate blood is not produced
(c)
heart wall becomes weaker
(d)
none of these
75.
Blood pressure lower than 120/80 mm Hg may be a sign of
(a)
hypotension
(b)
hypertension
(c)
respiratory problem (d)
disease
76.
77.
78.
79.
80.
(a)
Pulmonary artery drains the deoxygenated blood from
(a)
right atrium
(b)
right ventricle
(c)
left atrium
(d)
left ventricle
(b)
Pulmonary artery is different from pulmonary vein
because it has
(a)
larger lumen
(b)
thick muscular walls
(c)
no endothelium
(d)
valves
(c)
The pericardium and the pericardial fluid help in
(a)
protecting the heart from friction, shocks and
keeps it moist
(b)
pumping the blood
(c)
receiving the blood from various parts of the body
(d)
None of the above
Choose the schematic diagram which properly represents
pulmonary circulation in humans
(a)
(d)
Heart wall is made up of
(a)
fibrous pericardium, epicardium, visceral layer
(b)
serous pericardium, myocardium, endocardium
(c)
fibrous pericardium, parietal pericardium, visceral
pericardium
(d)
epicardium, myocardium, endocardium
82.
Foramen ovale
(a)
connects the two atria in the foetal heart
(b)
is a condition in which the heart valves do not
completely close
(c)
is a shallow depression in the interventricular
septum
(d)
is a connection between the pulmonary trunk and
the aorta in the foetus
Oxygenated
o
Right ventricle 
blood
Deoxygenated
o
Right ventricle 
blood
Oxygenated
o Left auricle
Lungs 
blood
(c)
Deoxygenated
o
Left auricle 
blood
Oxygenated
o Right ventricle
Lungs 
blood
(d)
A-Aorta B-Pulmonary vein C-Pulmonary arteries
D-Left ventricle E-semilunar valves F-Left auricle
G-Right auticle H-Superior vena cava I-Right
ventricle J-Tricuspid valves K-Inferior vena cava
A-Aorta B-Pulmonary artery C-Pulmonary veins
D-Left auricle E-Tricuspid valves F- Left ventricle
G-Right ventricle H- Inferior vena cava I-Right
ventricle J- Semilunar valves K-Superior vena
cava
A-Aorta B-Superior vena cava C- Inferior vena
cava D-Right ventricle E-Tricuspid valves and
mitral valves F-Right auticle G-Left auricle HPulmonary vein I- Left ventricle J-Semilunar
valves K-Pulmonary artery
A-Aorta B-Superior vena cava C-Inferior vena
cava D-Left ventricle E-Semilunar valves F-Left
auricle G-Right auticle H-Pulmonary artery I-Right
ventricle J-Tricuspid valves K-Pulmonary vein
81.
Deoxygenated
o Left auricle
Lungs 
blood
(b)
In diagram of the vertical section of human heart given
here, certain parts have been indicated by alphabets.
Choose the answer in which these alphabets have been
correctly matched with the parts they indicate.
Oxygenated
o
Left auricle 
blood
Deoxygenated
o Right ventricle
Lungs 
blood
Circulation
..144..
83.
84.
85.
86.
87.
88.
89.
Tricuspid valve is found in between
(a)
sinus venosus and right auricle
(b)
right auricle and right ventricle
(c)
left ventricle and left auricle
(d)
ventricle and aorta
The thread-like tendons of papillary muscles inserted
upon the flaps of tricuspid and bicuspid valves ae
(a)
chordae tendinae (b)
yellow elastin fibres
(c)
reticulate fibres
(d)
collagen fibres
Which of the following chamber of heart has the thickest
muscular wall ?
(a)
Left auricle
(b)
Left ventricle
(c)
Right ventricle
(d)
Right auricle
(a)
(b)
(c)
(d)
Right part of heart is concerned with
(a)
oxygenating the blood
(b)
carrying deoxygenated blood to lungs for
oxygenating
(c)
supplying blood to heart muscles
(d)
carrying oxyganated blood to all parts of body
91.
The oxygenated and deoxygenated blood in man do not
mix because of
(a)
inter auricular septum
(b)
interventriculas septum
(c)
both a and b
(d)
auriculo-ventricular septum
92.
Papillary muscles are present in
(a)
ventricles of heart (b)
(c)
hypothalamus
(d)
muscular
ligamentous
The first heart sound is produced when
(a)
diastole begins
(b)
semilunar valve close quickly
(c)
interventricular pressure decreases
(d)
bicuspid and tricuspid valve close quickly
94.
Cardiac output signifies the amount of blood
(a)
entering the heart per unit time
(b)
entering the lung per unit time
(c)
leaving the heart per unit time
(d ) leaving the lung per unit time
95.
Cardiac output is defined as the amount of blood
(a)
received by the heart in one minute
(b)
pumped by each ventricle per minute
(c)
pumped by both ventricles per second
(d ) pumped by the left atrium per hour
96.
Cardiac output is
(a)
the product of heart rate and stroke volume
(b)
the product of auricular and ventricular volume
(c)
the blood pumped the heart in one minute
(d ) Both (a) and (c)
97.
The cardiac output in man under resting conditions is
about
(a)
2 L/min
(b)
4 L/min
(c)
5 L/min
(d ) 7 L/min
The diagram shows the heart with its main blood vessels.
Circulation
ventricles of brain
medulla oblongata
93.
The pre-caval veins collect blood from
(a)
trunk and hind limbs
(b)
fore limbs and hind limbs
(c)
head and fore limbs
(d)
head and hind limbs
Which blood vessels carry oxygenated blood to the body
tissues and deoxygenated blood away from the body
tissues ?
deoxygenated blood
away from body tissues
A
C
A
D
90.
Bicuspid valve allows blood from
(a)
right auricle to left ventricle
(b)
right auricle to right ventricle
(c)
left auricle to left ventricle
(d)
post caval to heart
Nature of valves in the heart is
(a)
membranous
(b)
(c)
tendinous
(d)
Oxygenated blood to
body tissues
B
B
C
C
..145..
98.
The volume of blood each ventricle pumps out during a
cardiac cycle is about
(a)
70 mL
(b)
5000 mL
(c)
7L
(d)
1200 mL
99.
Which part of the circulatory system serves to supply
blood to the heart?
(a)
Coronary
(b)
Portal
(c)
Pulmonary
(d)
Systemic
100.
101.
In diastole, heart is filled by
(a) mixed blood
(b)
(c) oxygenated blood
(d)
103.
‘Heart of Heart’ is
(a)
SA- node
(c)
bundle of His
(b)
(d)
AV-node
Purkinje fibres
Pacemaker of heart is
(a)
AV node
(c)
SA node
(b)
(d)
bundle of His
Purkinje fibres
106.
107.
109.
Bundle of His is a network of
(a)
Nerve fibres found throughout the heart
(b)
Muscle fibres distributed throughout the heart
walls
(c)
Muscle fibres found only in the ventricle wall
(d)
Nerve fibres distributed in ventricles
110.
The correct route through which pulse-making impulse
travels in the heart is
(a)
AV node o Bundle of His o SA node o Purkinje
fibres o Heart muscles
(b)
AV node o SA node o Purkinje fibres o Bundle
of His o Heart muscles
(c)
SA node o Purkinje fibres o Bundle of His o
AVV node o Heart muscles
(d)
SA node o AV node o Bundle of His o Purkinje
fibres o Heart muscles
111.
Adrenaline directly affects
(a)
islets of Langerhans
(b)
sinoatrial node
(c)
oxyntic cells of stomach
(d)
dorsal root ganglia of spinal cord
112.
Tachycardia is
(a)
fast heart rate
(c)
stop heart rate
venous blood
deoxygenated blood
Innervation of heart in the intact higher animals is
primarily meant for
(a)
initiation of heart beat
(b)
regulation of heart beat
(c)
release of acetylcholine only
(d )
release of adrenaline only
105.
The atrio-ventricular node is situated
(a)
near the bicuspid valve
(b)
in between the atrium
(c)
at the base of inter-auricular septum
(d ) in the left ventricle
Cardiac cycle in man takes about
(a)
0.5 s
(b)
1.0 s
(c)
1.2 s
(d ) 0.8 s
102.
104.
108.
Since it is the sinu-auricular node, which initiates the
impulses in the heart of mammal, the heart is called
(a)
cholinergic
(b)
adrenergic
(c)
neurogenic
(d ) myogenic
SA-node is located in
(a)
lower lateral wall of right atrium
(b)
upper lateral wall of right atrium
(c)
upper lateral wall of left atrium
(d)
lower lateral wall of left atrium
Impulse originating from sinu-atrial node are transmitted
to the
(a)
atrio-ventricular node
(b)
bundle of His
(c)
pacemaker
(d)
Purkinje system
(b)
(d)
slow heart rate
normal heart rate
113.
Heart rate is increased by all of the following except
(a)
anoxia
(b)
moderate CO2 excess
(c)
elevated body temperature
(d ) increased intracranial pressure
114.
Myocardial infarction is
(a)
infection of heart muscles
(b)
death of heart muscles
(c)
clot in blood vessel
(d ) breakage of coronary vessel.
115.
A heart murmur indicates a defective
(a)
Sinuauricular node
(b)
Atrioventricular node
(c)
Bundle of His
(d)
Heart valve
Circulation
..146..
116.
117.
118.
Match Column - I with Column - II and select the correct
option from the codes given below
Column-I
Column-II
(A) Heart failure
(i)
Heart muscle is
suddenly damaged
by an inadequate
blood supply
(B)
Cardiac arrest
(ii)
Chest pain due to
inadequate O2
reaching the heart
muscles
(C)
Heart attack
(iii) Atherosclerosis
(D)
Coronary artery
(iv) Heart not pumping
disease (CAD)
blood effectively
enough to meet the
needs of the body
(E)
Angina pectoris
(v)
Heart stops beating
(a)
A - (iv), B - (v), C - (i), D - (iii), E - (ii)
(b)
A - (v), B - (iv), C - (i), D - (iii), E - (ii)
(c)
A - (iv), B - (v), C - (i), D - (ii), E - (iii)
(d)
A - (v), B - (iv), C - (ii), D - (iii), E - (i)
ECG is a measure of
(a)
rate of heart beat
(b)
difference in electric potential
(c)
volume of blood pumped
(d)
ventricular contraction
ECG method is the way to detect
(a)
heart attack
(b)
heart block
(c)
coronary thrombosis (d ) all above
119.
During ECG of heart ventricular systole is during
(a)
PQR
(b)
PQ
(c)
QR
(d)
ST
120.
The repolarization phase of cardiac cycle is represented
by which portion of a ECG?
(a)
P
(b)
QRS
(c)
S
(d ) T
121.
Which of the following correctly explains a phase/ event
in cardiac cycle in a standard electrocardiogram?
(a)
QRS complex indicates atrial contraction.
(b)
QRS complex indicates ventricular depolarization
(c)
Time between S and T represents atrial systole.
(d)
P-wave indicates beginning of ventricular
contraction
122.
ECG depicts the depolarisation and repolarisation
processes during the cardiac cycle. In the ECG of a
normal healthy individual one of the following waves is
not represented.
(a)
Depolarisation of atria
(b)
Repolarisation of atria
(c)
Depolarisation of ventricles
(d)
Repolarisation of ventricles
123.
Which of the following statements is correct ?
(a)
The T-wave in an ECG represents excitation of
ventricles
(b)
The sum of P and T waves in a given time period
can determine the heart beat rate of an individual
(c)
The end of the P-wave marks the end of the systole
(d)
In a standard ECG, a person is connected to the
machine with three electrical limb leads
124.
If there is a blockage between the AV node and AV bundle,
how will this affect the appearance of the EGG ?
(a)
P-R interval would be smaller
(b)
QRS interval wo uld be longer
(c)
there would be more P waves than QRS complexes
(d ) there would be more QRS complexes than P waves
125.
Which of the following is the diagrammatic representation
of standard electrocardiogram (ECG) ?
(a)
(b)
(c)
(d)
Circulation
..147..
ANSWER KEY
EXERCISE – 1
1. (c)
2. (b)
3. (b)
4. (b)
5.
11. (c)
12. (a)
13. (d)
14. (a)
21. (b)
22. (a)
23. (d)
31. (d)
32. (a)
41. (b)
(b)
6. (c)
7. (b)
8. (a)
9. (b)
10. (c)
15. (b)
16. (a)
17. (c)
18. (d)
19. (b)
20. (d)
24. (a)
25. (c)
26. (d)
27. (d)
28. (d)
29. (a)
30. (b)
33. (a)
34. (d)
35. (d)
36. (a)
37. (c)
38. (b)
39. (c)
40. (b)
42. (b)
43. (c)
44. (b)
45. (c)
46. (b)
47. (b)
48. (c)
49. (d)
50. (b)
51. (a)
52. (c)
53. (a)
54. (a)
55. (b)
56. (d)
57. (c)
58. (b)
59. (c)
60. (d)
61. (c)
62. (a)
63. (b)
64. (d)
65. (d)
66. (b)
67. (d)
68. (d)
69. (a)
70. (a)
71. (c)
72. (b)
73. (a)
74. (a)
75. (a)
76. (b)
77. (b)
78. (a)
79. (b)
80. (b)
81. (d)
82. (a)
83. (b)
84. (a)
85. (b)
86. (c)
87. (a)
88. (c)
89. (c)
90. (b)
91. (c)
92. (a)
93. (d)
94. (c)
95. (b)
96. (d)
97. (c)
98. (a)
99. (a)
100. (d)
101. (d)
102. (b)
103. (a)
104. (c)
105. (d)
106. (b)
107. (a)
108. (c)
109. (c)
110. (d)
111. (b)
112. (a)
113. (d)
114. (b)
115. (d)
116. (a)
117. (b)
118. (d)
119. (d)
120. (d)
121. (b)
122. (b)
123. (d)
124. (c)
125. (d)
Dream on !!
[\]^[\]^
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