The Circulatory System

Solutions for Biology, Class 6, ICSE

Choose The Odd One

1 question

Question 1

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
Choose The Odd One

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

Fill In The Blanks

1 question

Question 1

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.
Fill In The Blanks

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

Long Answer Questions

9 questions

Question 1

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

Long Answer Questions

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:

Name the three kinds of blood vessels found in human beings. With the help of suitable diagrams, differentiate between them. The Circulatory System, Concise Biology Solutions ICSE Class 6.
ArteriesVeinsCapillaries
An artery is a vessel which carries the blood away from the heart to other parts of the body.A vein is a vessel which carries the blood from an organ towards the heart.Capillaries are the terminal branches of an artery, which rejoin to form a vein.
An artery has thick, elastic and more muscular walls.A vein has thin and less muscular walls with valves.Walls of the capillary are made up of single layer of cells (endothelium) with no muscles.
The blood in it flows with jerk and under great force.The valves prevent the back flow of the blood flowing towards the heart.The wall of capillary is very thin, to enable an exchange of nutrients waste products and gases between the blood and the body fluids.

Question 2

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

Long Answer Questions

Answer:

Difference between White blood cells and Red blood cells:

White Blood CellsRed Blood Cells
WBCs are amoeboid having irregular shape.RBCs are circular or biconcave disc shaped.
WBCs have distinct oval or lobed nucleus.RBCs do not have nucleus at maturity.
WBCs are larger than RBCs.RBCs are small in size.
RBCs have red colour due to the presence of haemoglobin protein.WBCs are colourless and they lack haemoglobin.
RBCs 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.WBCs provide immunity by destroying the disease causing germs and producing antibodies.

Question 3

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?

Long Answer Questions

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.

Question 4

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

Given alongside is a diagram of human heart showing its internal structure. Label the parts marked 1 to 5. The Circulatory System, Concise Biology Solutions ICSE Class 6.

(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?

Long Answer Questions

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

Question 5(i)

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

Long Answer Questions

Answer:

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

ArteriesVeins
Arteries have thick, elastic and muscular walls to withstand high pressure.Veins have thin and less muscular walls as the blood pressure is lower.
They lack valves (except the pulmonary trunk and the aorta).Valves are usually present to prevent the backflow of blood.
Arteries are usually, deeply placed in the body.Veins are usually placed more superficially.

Question 5(ii)

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

Long Answer Questions

Answer:

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

AtriaVentricles
The atria are the two upper chambers of the heart.The ventricles are the two lower chambers of the heart.

Question 5(iii)

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

Long Answer Questions

Answer:

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

Blood group 'AB'Blood group 'O'
The persons whose RBCs have both types of antigens, i.e. both A and B, belong to the 'AB' blood group.The persons whose RBCs have no antigens, i.e., neither A nor B have the 'O' blood group.

Question 5(iv)

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

Long Answer Questions

Answer:

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

Pulmonary CirculationSystemic Circulation
In pulmonary circulation, the blood flows from the heart to the lungs and back to the heart.In systemic circulation, the blood flows from the heart to the entire body (except lungs) and back to the heart.

Question 5(v)

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

Long Answer Questions

Answer:

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

Pulmonary ArteryPulmonary Vein
The pulmonary artery carries deoxygenated blood from the heart to the lungs.The pulmonary vein carries oxygenated blood from the lungs back to the heart.

Match The Following

1 question

Question 1

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

Column AColumn B
(i) Haemoglobin(a) Antibodies
(ii) Heart(b) Distributing chambers
(iii) Leukocytes(c) Oxygen carrier
(iv) Atria(d) Pumping organ
(v) Ventricles(e) Receiving chambers
Match The Following

Answer:

Column AColumn B
(i) Haemoglobin(c) Oxygen carrier
(ii) Heart(d) Pumping organ
(iii) Leukocytes(a) Antibodies
(iv) Atria(e) Receiving chambers
(v) Ventricles(b) Distributing chambers

Multiple Choice Questions

10 questions

Question 1

Function of WBCs is to

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

Answer:

Provide immunity

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

Question 2

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
Multiple Choice Questions

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.

Question 3

Nucleus is absent in

  1. RBCs
  2. WBCs
  3. All blood cells
  4. Liver cells
Multiple Choice Questions

Answer:

RBCs

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

Question 4

The only artery which carries deoxygenated blood is

  1. Hepatic artery
  2. Pulmonary artery
  3. Aorta
  4. Renal artery
Multiple Choice Questions

Answer:

Pulmonary artery

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

Question 5

Sphygmomanometer measures

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

Answer:

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

Question 6

Pulmonary vein carries

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

Answer:

Oxygenated blood

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

Question 7

The blood tastes saltish due to the presence of dissolved:

  1. Sodium chloride
  2. Potassium chloride
  3. Ammonium nitrate
  4. Sodium nitrate
Multiple Choice Questions

Answer:

Sodium chloride

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

Question 8

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

  1. Liver
  2. Heart
  3. Kidney
  4. Lung
Multiple Choice Questions

Answer:

Heart

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

Question 9

Haemoglobin consists of :

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

Answer:

Iron + Proteins

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

Question 10

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

  1. Pulmonary artery
  2. Aorta
  3. Pulmonary vein
  4. Vena cavae
Multiple Choice Questions

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.

Short Answer Questions

15 questions

Question 1(a)

Differentiate between Platelets and WBC.

Short Answer Questions

Answer:

Difference between Platelets and WBCs:

PlateletsWBCs
Platelets help in clotting of blood.WBCs provide immunity by destroying the disease causing germs and producing antibodies.
Platelets are the smallest of the blood cells.WBCs are larger than RBCs and Platelets.
Platelets does not have a nucleus.WBCs have a distinct oval or lobed nucleus.

Question 1(b)

Differentiate between Pulmonary artery and Pulmonary vein

Short Answer Questions

Answer:

Difference between Pulmonary artery and Pulmonary vein:

Pulmonary arteryPulmonary vein
The Pulmonary artery arises from the right ventricle of the heart.The Pulmonary vein drains blood in the left atrium of the heart.
It carries deoxygenated blood from the right auricle of the heart to each lung.It carries oxygenated blood from each lung to the left atrium of the heart.

Question 1(c)

Differentiate between Vena cava and Aorta

Short Answer Questions

Answer:

Difference between Vena cava and Aorta:

Vena cavaAorta
Vena cava is a large vein.Aorta is the largest artery.
It carries deoxygenated blood from the upper and lower parts of the body to the right auricle of the heart.It leaves the left auricle of the heart carrying oxygenated blood to all parts of the body through its branches.

Question 1(d)

Differentiate between RBC and WBC

Short Answer Questions

Answer:

Difference between RBC and WBC:

RBCWBC
RBC do not have nucleus at maturity.WBC have a large distinct oval or lobed nucleus .
WBC are larger than RBC.RBC are small in size.
RBC have red colour due to the presence of haemoglobin protein.WBC are colourless and they lack haemoglobin.
RBC 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.WBC provide immunity by destroying the disease causing germs and producing antibodies.

Question 2

Give any three differences between an Artery and a Vein.

Short Answer Questions

Answer:

Three differences between an Artery and a Vein are:

ArteryVein
Arteries carry blood away from the heart to various body parts.Veins carry blood from different body parts to the heart.
Arteries have thick elastic and more muscular walls.Veins have thin and less muscular walls.
Arteries carry oxygenated blood (except the pulmonary artery).Veins carry deoxygenated blood (except the pulmonary vein).

Question 3

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

Short Answer Questions

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.

Question 4

What is the role of haemoglobin in the blood?

Short Answer Questions

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.

Question 5

In which organ of our body does blood become oxygenated?

Short Answer Questions

Answer:

Blood becomes oxygenated in the lungs.

Question 6

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

Short Answer Questions

Answer:

The left side of the heart contains oxygenated blood.

Question 7

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

Short Answer Questions

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.

Question 8

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.
Short Answer Questions

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

Question 9

Define the terms given below :

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

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.

Question 10

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.
Short Answer Questions

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.

Question 11

Write one important role of each of the following:

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

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.

Question 12

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

Short Answer Questions

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.