The Circulatory System

Function of WBCs is to

1. Transport oxygen
2. Help in clotting of blood
3. Provide immunity
4. Provide storage of food

Answer

Provide immunity

Reason — WBCs provide immunity by destroying the disease causing germs and producing antibodies.

Blood Capillary is a

1. Broad tube
2. Artery with thick wall
3. Vein with large lumen
4. Narrow tube made up of endothelium only

Answer

Narrow tube made up of endothelium only

Reason — Blood capillary is narrow blood vessel whose walls have a single layer of cells called endothelium.

Nucleus is absent in

1. RBCs
2. WBCs
3. All blood cells
4. Liver cells

Answer

RBCs

Reason — RBCs have no nucleus because they need space for haemoglobin to store more amount of oxygen.

The only artery which carries deoxygenated blood is

1. Hepatic artery
2. Pulmonary artery
3. Aorta
4. Renal artery

Answer

Pulmonary artery

Reason — Pulmonary artery leaves the right ventricle of the heart carrying the deoxygenated blood to the lungs for oxygenation.

Sphygmomanometer measures

1. Pulse rate
2. Heart beat
3. Blood pressure
4. Brain activity

Answer
Blood pressure

Reason — Sphygmomanometer is an instrument which is used to find out blood pressure of the body.

Pulmonary vein carries

1. Oxygenated blood
2. Deoxygenated blood
3. Glucose-rich blood
4. CO₂ laden blood

Answer

Oxygenated blood

Reason — Oxygenated blood from the lungs returns to the left auricle via pulmonary veins.

The blood tastes saltish due to the presence of dissolved:

1. Sodium chloride
2. Potassium chloride
3. Ammonium nitrate
4. Sodium nitrate

Answer

Sodium chloride

Reason — The blood tastes saltish due to dissolved minerals like sodium chloride.

Which of the following is an organ of the human cardiovascular system ?

1. Liver
2. Heart
3. Kidney
4. Lung

Answer

Heart

Reason — The blood is transported to all parts of the body by a pumping organ, i.e., heart, and the blood vessels.

Haemoglobin consists of :

1. Iodine + Proteins
2. Iron + Amino acids
3. Iron + Proteins
4. Globin + Proteins

Answer

Iron + Proteins

Reason — Haemoglobin is an iron and protein compound found within RBCs. It acts as the "oxygen-carrier".

Which of the following blood vessels carries deoxygenated blood to the heart ?

1. Pulmonary artery
2. Aorta
3. Pulmonary vein
4. Vena cavae

Answer

Vena cavae

Reason — The Superior Vena Cava and the Inferior Vena Cava brings deoxygenated blood from the upper and lower parts of the body to the right auricle of the heart.

Fill in the blanks with suitable words :

1. The colour of a red blood cell is due to ...............
2. The two lower chambers of the heart are called ...............
3. The blood plasma contains dissolved substances such as ............... and ...............
4. The ............... artery takes the blood from the ventricles to the lungs.
5. The instrument used to find out the blood pressure is known as ...............
6. The blood loaded with carbon dioxide from the body comes into the ............... of the heart.
7. The oxygen-rich blood from the lungs comes into ............... of the heart.
8. The oxygen-rich blood is pumped into different parts of the body through ...............
9. The carbon dioxide loaded blood from the right ventricle is pumped into the lungs through ............... artery.

Answer

1. Haemoglobin
2. Ventricles
3. Nutrients, Proteins, waste products and Hormones
4. Pulmonary
5. Sphygmomanometer
6. Right Auricle
7. Left Ventricles
8. Aorta
9. Pulmonary

Match the terms given in column A with those of column B:

Answer

Given below are sets of four terms. Choose the odd one and write the category of the remaining terms :

1. Erythrocytes, Leukoplasts, Leukocytes, Thrombocytes
2. Arteries, Atria, Capillaries, Veins
3. Heart, Kidney, Blood vessels, Blood
4. RBCs, WBCs, Haemoglobin, Platelets
5. Diaphragm, Left atrium, Right ventricle, Pulmonary artery

Answer

1. Odd one — Leukoplasts
   Category of the remaining terms — Corpuscles (Blood cells)

2. Odd one — Atria
   Category of the remaining terms — Blood vessels

3. Odd one — Kidney
   Category of the remaining terms — Parts of Circulatory System

4. Odd one — Haemoglobin
   Category of the remaining terms — Corpuscles (Blood cells)

5. Odd one — Diaphragm
   Category of the remaining terms — Parts of the heart

Differentiate between Platelets and WBC.

Answer

Difference between Platelets and WBCs:

Differentiate between Pulmonary artery and Pulmonary vein

Answer

Difference between Pulmonary artery and Pulmonary vein:

Differentiate between Vena cava and Aorta

Answer

Difference between Vena cava and Aorta:

Differentiate between RBC and WBC

Answer

Difference between RBC and WBC:

Give any three differences between an Artery and a Vein.

Answer

Three differences between an Artery and a Vein are:

Blood consists of two parts - a liquid part and a cellular part. Name these parts and briefly describe them.

Answer

Blood is a red coloured fluid which consists of two parts:

1. Liquid part — The liquid part of the blood is called Plasma. Plasma is yellow in colour. 90% of Plasma is water and the remaining 10% consists of dissolved proteins, nutrients, waste product and hormones.
2. Cellular part — The cellular part of the blood is called Corpuscles. The corpuscles are of three types:
   1. Red Blood Cells (RBCs) — RBCs are also called as Erythrocytes. They carry oxygen from lungs to all the body tissues and cells and remove carbon dioxide produced in the cells and carry it back to the lungs. RBCs are circular or biconcave disc shaped. A mature RBC does not contain nucleus. Haemoglobin present in RBCs helps in transport of oxygen and gives them the red colour.
   2. White Blood Cells (WBCs) — WBCs are also called Leukocytes. They are colourless and lack haemoglobin. They are larger than RBCs and have a distinct oval or lobed nucleus. WBCs provide immunity by destroying the disease causing germs and producing antibodies
   3. Platelets — The platelets are also called Thrombocytes. They are round in shaped and the smallest in size. They help in the clotting of blood which prevents excessive blood loss and direct entry of disease causing germs into the blood through cuts and wounds.

What is the role of haemoglobin in the blood?

Answer

Haemoglobin is an iron and protein compound present in the Red Blood Cells (RBCs). It acts as the Oxygen carrier as it binds with Oxygen transporting it to all the body tissues and cells. It also helps to remove carbon dioxide produced in the cells and carry it back to the lungs.

In which organ of our body does blood become oxygenated?

Answer

Blood becomes oxygenated in the lungs.

Which side of the heart (left or right) contains oxygenated blood?

Answer

The left side of the heart contains oxygenated blood.

Name the disease in which the number of platelets reduces to 25,000 - 30,000 per cu mm of blood. State its major symptoms.

Answer

Dengue fever is one such disease in which the number of platelets reduces to 25,000 - 30,0000 per cu mm of blood. The major symptoms of dengue are high fever, rashes or red spots on body, vomiting, pain in abdomen or back of the eyes and muscles.

Name the following :

1. Three components of circulatory system
2. Three kinds of blood vessels
3. Three kinds of corpuscles
4. Two types of blood circulation in human body
5. Four categories of blood groups on the basis of the proteins found on the surface of RBCs.

Answer

1. Blood, Blood vessels and Heart
2. Arteries, Veins and Capillaries
3. Erythrocytes (RBCs), Leukocytes (WBCs), Thrombocytes (Platelets)
4. Pulmonary Circulation and Systemic Circulation
5. A, B, AB, and O

Define the terms given below :

1. Haemoglobin
2. Capillaries
3. Aorta
4. Universal donor
5. Blood pressure

Answer

1. Haemoglobin — Haemoglobin is an iron and protein compound that is found within the Red Blood cells. It acts as the "oxygen-carrier".

2. Capillaries — Capillaries are the terminal branches of an artery, which rejoin to form a vein.

3. Aorta — The aorta is the largest artery in the body and carries oxygenated blood from the left ventricle to all parts of the body through its branches.

4. Universal donor — A person with O blood group can give blood to a person of any blood type and is therefore called a universal donor.

5. Blood pressure — The pressure exerted by the blood on the walls of the arteries while flowing through them is called blood pressure.

Correct the following statements by changing the first/ last word only :

1. Robert Hooke identified the different types of blood groups.
2. A faster heart beat is usually an indication of hypotension.
3. WBCs produce special substances called antigens.
4. Thrombocytes contain haemoglobin.
5. Arteries possess valves.

Answer

1. Karl Landsteiner identified the different types of blood groups.
2. A faster heart beat is usually an indication of hypertension.
3. WBCs produce special substances called antibodies.
4. Erythrocytes contain haemoglobin.
5. Veins possess valves.

Write one important role of each of the following:

1. Erythrocytes
2. Thrombocytes
3. Arteries
4. Vena cavae
5. Heart

Answer

1. Erythrocytes contain an iron and protein compound called Haemoglobin that acts as the "oxygen-carrier".

2. The Thrombocytes help in the clotting of blood which prevents excessive blood loss and direct entry of disease causing germs into the blood through cuts and open wounds.

3. Arteries are crucial blood vessels that carry the blood away from the heart (oxygenated blood) to different parts of the body.

4. The vena cava's primary role is to return deoxygenated blood from the body back to the heart.

5. The heart, acting as a pump, pushes and receives the blood to and from the whole body through the blood vessels.

What are the two diseases in which the number of platelets in the human body are lowered to a great extent ?

Answer

The two diseases in which the number of platelets in the human body are lowered to a great extent are:

1. Purpura
2. Dengue.

Name the three kinds of blood vessels found in human beings. With the help of suitable diagrams, differentiate between them.

Answer

The three kinds of blood vessels found in human beings are Arteries, Veins and Capillaries.

Below diagram shows the differences between Artery, Vein and Capillaries:

State briefly, the difference between white blood cells and the red blood cells.

Answer

Difference between White blood cells and Red blood cells:

You can see some blood vessels on the outside of the hands specially in older people.Are those veins or arteries? How can you confirm your answer?

Answer

These blood vessels seen on the outside of the hands are Veins. Usually, arteries are deeply placed in the body whereas Veins are placed more superficially.

Given alongside is a diagram of human heart showing its internal structure. Label the parts marked 1 to 5, and answer the following questions.

(a) Which type of blood is carried by the blood vessel marked 2?

(b) Name the main artery which takes the blood from heart to different parts of the body?

(c) Which chamber of the heart receives oxygenated blood from the lungs?

Answer

The marked parts are:

1. Left pulmonary artery
2. Superior vena cava
3. Left pulmonary vein
4. Right auricle
5. Left ventricle

a) Deoxygenated blood is carried by the blood vessel marked 2 (Superior vena cava).

b) Aorta

c) Left auricle

Distinguish between arteries and veins on the basis of their structure.

Answer

Differences between arteries and veins on the basis of their structure:

Distinguish between atria and ventricles on the basis of their location in the heart.

Answer

Differences between atria and ventricles on the basis of their location in the heart:

Distinguish between Blood groups 'AB' and 'O' on the basis of antigens.

Answer

Differences between Blood groups 'AB' and 'O' on the basis of antigens:

Distinguish between pulmonary and systemic circulation on the basis of direction of blood flow.

Answer

Differences between pulmonary and systemic circulation on the basis of direction of blood flow:

Distinguish between pulmonary artery and pulmonary vein on the basis of the kind of blood they carry.

Answer

Differences between pulmonary artery and pulmonary vein on the basis of the kind of blood they carry: