Blood is a red colored fluid connective
tissue which consists of 55% plasma
and 45% blood cells.
The components of blood are as
follows:
1. Plasma
2. Red Blood Cells (RBC)
3. White Blood Cells (WBC)
4. Platelets
2. The main function of blood are as
follows:
1. It carries oxygen and provides it to all
the parts of the body.
2. It contains WBC which protects our
body from bacteria, viruses etc
3. It transports digested food to various
parts of the body.
4. It transports harmful substances like
carbon dioxide, urea, uric acid etc. to
the excretory organs.
3.
1.
RBCs/ WBCs
1. They are small in size./ 1. They are comparitively larger in size.
2. Nucleus is absent./ ii. Nucleus is present.
3. They help in respiration./ iii. They help in the defence of the body.
2.
Artery Veins
1. They are deep seated in the
muscle./ 1. They are superficially seated in the muscle.
2. They are thick walled./ 2. They are thin walled.
3. They do not contain valves./ 3. They contains valve to prevent the back flow of the
blood.
3.
Pulmonary artery Pulmonary vein
1. It carries de oxygenated blood to the
lungs.
/1. It carries oxygenated blood from the lungs to the
heart.
2. It arises from right ventricle to the lungs./ 2. It arises from the lungs from lungs to the heart.
4.
Tricuspid valve Bicuspid valve
1. It is present between right auricle and right
ventricle.
/1. It is found between left auricle and left
ventricle.
2. It consists of three membranous flaps or
cusps.
/2. It consists of two membranous flaps or
cusps.
4. Plasma is important because plasma
contains carries harmful substances
from the body. It also helps in
transportation of nutrition. It also
controls the flow and composition of
water in the blood.
The functions of plasma are as
follows:
1. It helps in blood clotting at the wounds.
2. It helps in transporting hormones
secreted from endocrine glands.
3. It transports digested food to different
parts of the body.
4. It balances the water content of the
blood.
5. The decrease in the RBCs in the body
causes the disease called anaemia.
6. The disadvantage of having more WBCs
is that the person suffers from blood
cancer.
7.
Heart is a strong hollow muscular
organ made up of cardiac muscle.
It is enclosed in a thin membrane
called pericardium and the fluid
present in between them is called
pericardial fluid. It allows free
movement of heart and protects it
from external shock and
mechanical injuries.
The human heart consists of four
chambers; two on each side. Two
upper and smaller chambers are
called right auricles and left
auricles. The two lower and larger
chambers are called right
ventricles and left ventricles. The
two auricles are separated by
interauricular septum and likewise
the ventricles are separated by
interventricular septum. The left
auricle and left ventricle are
separated by bicuspid valve and
the right auricle and right ventricle
are separated by tricuspid valve.
The right auricle has venacava;
the right ventricle has pulmonary
artery. The left auricle has
pulmonary veins and the left
ventricle has aorta.
8. Blood circulation is necessary for the
transportation of nutrients and oxygen
to tissues and collects their waste
products.
9.
10. The cells and tissues get molecules of
glucose, water, oxygen, hormones, etc.
from capillaries.
11. The blood vessels that take part in
blood circulation are arteries, veins
and, capillaries.
The function of arteries is:
To carry oxygenated blood from right
ventricles to the lung for purification.
The pulmonary artery carries
deoxygenated blood from the heart to
the lungs.
The function of veins is:
To carry deoxygenated blood from
lungs to the left auricle of the heart.
The pulmonary veins carry oxygenated
blood from lungs to the heart.
The functions of capillaries are:
To provide definite path for the flow of
blood.
To transfer the molecules of glucose,
water, oxygen, hormones, etc. to the
cells and tissues.
12. Superior venacava and inferior
venacava carries the impure blood to
the right auricle. Pulmonary vein carries
pure blood from lungs to the left
auricle.
1. The continuous rhythmic beat
throughout the life which is produced
due to the contraction and relaxation of
the heart is called heart beat. The heart
of a healthy adult person beats 60-70
times per minute.
The heat beat of a person
increases with the tension,
physical exercise, emotion,
fear, and fever.
2. The pressure exerted by the flow of
blood on the blood vessels is called
blood pressure.
If a person has a blood
pressure of 120/80 mmHg, Itit
means that the systolic blood
pressure of that person is 120
mmHg and the diastolic blood
pressure of that person is 80
mmHg.
13.
1. Left ventricle pumps out a large amount
of blood to the different parts of the
body through the aorta. For this, a great
force is required, which is provided by
its thick walls but right ventricles
supplyies impure blood towards the
lungs through pulmonary artery. For this
less force is required. So, the left
ventricles haves more number of
muscles than that of thr right ventricle.
2. The arteries carry oxygenated blood
from heart to different parts of our
body. It is deep seated. The blood
flows at high pressure and high speed
in arteries. To overcome the high blood
pressure in it the walls of arteries have
to be thick muscles.
3. Veins carry deoxygenated blood from
different parts of the body to our heart.
The blood pressure in it is low and
speed of blood is slow. So, the wall of
vein is thin and less elastic. There may
be chance of back flow of blood. So, to
prevent the back flow of blood veins
have valve.
4. In the right auricle, impure blood of the
whole body is poured through superior
venacava and inferior venacava
whereas pure blood is poured into a left
auricle from lungs through pulmonary
veins. Since a larger volume of blood is
collected in the right auricle than that
of the left auricle, right auricle is larger
than the left auricle.
1. Define circulatory system.
Ans: The system of the body transporting useful and waste materials to and from the cells and tissues is called the circulatory system.
2. Define pulmonary circulation.
Ans: The circulation of blood between the heart and lungs is called pulmonary circulation.
3. Define arteries.
Ans: Arteries are the blood vessels which carry blood away from the heart to different organs.
4. Define blood pressure.
Ans: The pressure exerted by blood on the walls of the arteries is called blood pressure.
5. Arteries are deep seated but veins are superficial. Why?
Ans: It is because blood flows at high pressure in arteries and at low pressure in veins, so to balance the pressure in and out of the blood vessels, they are found at different depth.
6. A person suffering from anemia feels weakness after a short walk. Why?
Ans: It is because, such people have very less number of RBCs in their blood, and so their blood cannot carry sufficient oxygen for the required amount of energy for the body.
7. Arteries are thick walled. Why?
Ans: The flow of light oxygenated blood in arteries is with high velocity exerting extreme pressure on the walls, so to balance the high pressure, arteries are thickly walled.
8. What is meant by a person's blood pressure is 140/90 mm of Hg?
Ans: It means a person has high blood pressure that is systolic pressure is 140 and diastolic pressure is 90mm Hg.
9. What is Sphygmomanometer?
Ans: The instrument which is used to measure the blood pressure is called sphygmomanometer.
10. Bleeding from an artery is dangerous, why?
Ans: Bleeding from an artery is dangerous because oxygenated blood flows with a high pressure in an artery. As a result, a large amount of blood loss occurs during bleeding, which may cause death.
11. Which blood vessel is used to draw the blood during blood donation, why?
Ans: During blood donation, the blood is drawn from the vein because veins are superficially located and blood flows in the vein with low pressure which makes the vein to identify easily and creates no problems with bleeding after the needle remains.
12. What is blood pressure? Write any two causes of high blood pressure. How can it be prevented?
Ans: The pressure exerted by the flow of the blood on the walls of the arteries is called blood pressure.
Following are the causes of high blood pressure;
i. Smoking.
ii. Lack of physical exercise.
High blood pressure can be prevented by the following ways.
i. Avoiding the habits such as smoking and drinking.
ii. Doing physical exercise regularly.
iii. Avoiding consumption of fatty, oily and spicy foods.
iv. Managing the stress.
13. Define blood vessels.
Ans: Blood vessels are a network of the tube-like structure of different sizes that carry blood away from the heart, transport it to the tissues and then return it to the heart.
14. Define veins.
Ans: Veins are the blood vessels which carry blood from different organs in the body back towards the heart.
15. Define capillaries.
Ans: Capillaries are the blood vessels which joins the veins and arteries in the form of network.
16. Vein contains valves. Why?
Ans: Veins contains valves to prevent the back flow of impure blood.
17. Define valves.
Ans: Valves are the muscular flaps, which allow unidirectional flow of blood i.e. it prevents backflow of the blood.
18. What are blood vessels?
Ans: Blood vessels are the hollow and tubular vessels through which the blood flows.
19. Differentiate between arteries and veins.
Ans:
| Arteries | Veins |
| 1. Arteries carry blood away from the heart (except pulmonary artery). | 1. Veins carry blood towards the heart (except pulmonary vein). |
| 2. Arteries are deep-seated (located deep in the body). | 2. Veins are superficially located (located close to the skin). |
20. What type of diseases diabetes?
Ans: Diabetes is the disease caused by the increase in blood sugar level.
21. Write a cause of diabetes. What symptoms are seen in the persons suffering from diabetes? What do you suggest for the people to prevent themselves from diabetes?
Ans: There are two types of diabetes, i.e. Type I and Type II diabetes.
Cause of Type I diabetes is lack of insulin hormone due to the destruction of cells of the pancreas.
The symptoms are;
i. Frequent urination.
ii. Excessive thirst and hunger.
iii. Tiredness.
iv. Delay in wound healing.
Following are the preventive measures of diabetes.
i. Do physical exercise regularly.
ii. Avoid smoking and drinking habit.
iii. Manage the stress by involving healthy and useful creational activity.
iv. Take a balanced diet.
22. Define haemoglobin.
Ans: Haemoglobin is the iron rich pigment present in RBC which is responsible for the red colour of the blood.
23. What is plasma?
Ans: Plasma is a liquid element, which is light-yellow in colour and alkaline in nature.
24. Write down the function of Plasma.
Ans: Plasma transports hormones and digested food to different parts of the body.
25. Define plasma. Donates blood is related with sodium citrate, why? Blood does not clot when it is inside the blood vessel, Give reasons?
Ans: Plasma is a transparent clear, yellowish fluid that contains 90% water and 10% other solids.
Donated blood is treated with sodium citrate to avoid blood clotting.
Blood does not clot when it is inside the blood vessel due to the presence of active natural anticoagulant called heparin. [Once, the blood comes in contact with air heparin becomes inactive and cannot prevent blood from clothing.
26. What is systolic blood pressure?
Ans: When the ventricles contract, the pressure of blood inside the arteries is the highest, this pressure is called systolic blood pressure.
27. Differentiate between erythrocytes and leucocytes.
Ans:
| Erythrocytes | Leucocytes |
| 1. These are red in colour. | 1. These are colourless. |
| 2. These are more in number. | 2. These are less in number. |
28. Veins have valves at intervals in their inner living whereas arteries do not have valves, why? Ans: Blood flows slowly with low pressure inside veins. So, valves are present in the veins at intervals to prevent the backflow of the blood whereas, blood flows faster with high pressure inside arteries. So, valves are absent in arteries as there is no chance of backflow of blood.
29. What is blood?
Ans: Blood is a fluid connective tissue in which blood cells are suspended in the plasma.
OR
30. Define blood.
Ans: Blood is a fluid connective tissue which consists of plasma and blood cells.
31. Where are RBC'S produced and destroyed?
Ans: RBC'S are produced in bone marrow and destroyed in spleen and liver.
32. What is haemoglobin?
Ans: Haemoglobin is an iron-rich protein which gives a red colour to the RBC's.
33. What happens when RBCs decreases in our body?
Ans: The decrease in the number of RBCs in our body causes anaemia.
34. Differentiate between plasma and blood corpuscles.
Ans:
| Plasma | Blood Corpuscles |
| 1. It is formed of water and solidmaterials. | 1. It is formed of WBCs, RBCs and platelets. |
| 2. It forms about 55% of the total blood volume. | 2. It forms about 45% of the total blood volume. |
35. Blood of persons living in the high mountain contains more red cells than the persons living in Terai, why?
Ans: At high Mountain, the concentration of oxygen is less, so more RBCs are required to fulfil the essential oxygen inside the body. Whereas, in Terai, the concentration of oxygen is high. So, less RBC's can fulfil the essential oxygen inside the body. Therefore, the blood of persons living in the high mountain contains more RBC's than the persons living in Terai.
36. A person suffering from anaemia feels tired after walking for a short period, why?
Ans: Anaemia is a condition of the body in which there is a deficiency of RBCs or haemoglobin in the blood. So, in a person suffering from anaemia, an adequate amount of oxygen cannot be supplied to the body due to the deficiency of RBC's or haemoglobin as a result required amount of energy is not released in the body.
Explanation: Since oxygen is required for the oxidation of food to release energy in the cells in the body. Therefore, he or she feels tired after walking for a short period.
37. WBCs are called soldiers of the body, why?
Ans: White blood cells are the cells which are responsible for protecting our body from the germs i.e. bacteria (microorganisms) by destroying or engulfing them or forming antibodies. Therefore, these are called Soldiers of the body.
38. Write on functions each of WBC, Plasma and Haemoglobin.
Ans: The functions of each of them are:
WBC's - They fight against germs and destroy the damaged cells by engulfing them.
Plasma - It transports respiratory gases, digested food, waste materials etc. to the respective sites.
Haemoglobin - It plays an important role in the transport of oxygen and carbon dioxide.
39. Define circulatory system.
Ans: The system of the body transporting useful and waste materials to and from the cells and tissues is called the circulatory system.
40. Define pulmonary circulation.
Ans: The circulation of blood between the heart and lungs is called pulmonary circulation.
41. Define systemic circulation.
Ans: The circulation of blood between the heart and body organs except lungs is called systemic circulation.
42. What is circulatory system?
Ans: The system of the body which helps in the transportation of oxygen and nutrients to the tissues and collects their waste product is called the circulatory system.
43. Name the parts of circulatory system.
Ans: The parts of the circulatory system are blood, heart and blood vessels.
44. Write any two differences between Systemic and Pulmonary circulation.
Ans:
| Systemic circulation | Pulmonary circulation |
| 1. The circulation of blood between the heart and different part of the body other than the lungs is called systemic circulation. | 1. The circulation of blood between the heart and the lungs is called pulmonary circulation. |
| 2. Oxygenated blood is circulated. | 2. Deoxygenated blood is circulated. |
45. Define heart beat.
Ans: One complete contraction and relaxation of the heart is called heartbeat.
46. Define heart.
Ans: The heart is a hollow conical and muscular pumping organ situated in the middle of the thoracic cavity in between two lungs.
47. Define pericardium.
Ans: The double-walled membranous sac that protects the heart is called pericardium.
48. Where are bicuspid and tricuspid valves present found?
Ans: Bicuspid value is present in between the left auricle and left ventricle.
Tricuspid valve is present in between the right auricle and right ventricle.
49. What is pericardial fluid?
Ans: It is the fluid present in pericardial cavity of the heart.
50. The wall of left ventricle of a human heart is thicker than that of right ventricle, why?
Ans: The left ventricle has to pump the blood to the aorta with the greatest force and the more pressure is exerted on its wall; whereas the right ventricle pumps the blood to the pulmonary artery with relatively less force and the less pressure is exerted on its wall. To withstand such a great pressure, left ventricle of a human heart is thicker than that of the right ventricle.
51. Write any two differences between auricles and ventricles.
Ans:
| Auricles | Ventricles |
1. Auricles are the blood receiving chamber. | 1. Ventricles are blood disturbing chambers. |
| 2. These are upper chambers of the heart. | 2. These are lower chambers of the heart. |
52. Differentiate between Mitral valve and Tricuspid valve.
Ans:
| Mitral valve | Tricuspid valve |
1. It is present between the left auricle and left ventricle. | 1. It is present between the right auricle and right ventricle. |
| 2. It consists of two flaps. | 2. It consists of three flaps. |