Human Body : Circulatory System
Exercise
Section I
A. Name the following.
1. The straw-coloured fluid in which the different blood cells are suspended.
= Plasma;
2. Blood cells that helps in blood clotting.
= Platelets;
3. The muscles that make up the walls of heart.
= Specialised Cardiac Muscles;
4. The artery in the body.
= Aorta;
5. The artery that carries deoxygenated blood.
= Pulmonary;
B. Choose the correct option.
1. The blood cells that defend the body against germs.
a. RBCs. [ ]
b. Platelets. [ ]
c. WBCs. [✓]
d. Erythrocytes. [ ]
2. Oxygenated blood from the lungs is received by this.
a. Right auricle. [ ]
b. Right ventricle. [ ]
c. Left auricle. [✓]
d. Left ventricle. [ ]
3. The type of blood vessel that carries blood to the heart.
a. Artery. [ ]
b. Vein. [✓]
c. Aorta. [ ]
d. Capillary. [ ]
4. The pressure wave transmitted through the arterial system due to ventricular contraction.
a. Blood pressure. [ ]
b. Pulse. [✓]
c. Heart beat. [ ]
d. Cardiac cycle. [ ]
5. The blood group of a person with no antigens on RBC.
a. A. [ ]
b. B. [ ]
c. AB. [ ]
d. O. [✓]
C. Choose the correct option to fill in the blanks.
1. A red blood cell is biconcave
(biconvex/biconcave) in shape and
does not contain (contain/does not contain) a nucleus.
2. Blood flows at a high (low/high)
pressure in the arteries.
3. Arteries carry oxygenated
(oxygenated/deoxygenated) blood.
4. The plasma is straw (straw/red) -coloured fluid component of the blood and the RBC (platelet/RBC) is the red-coloured pigment.
5. The largest vein in the human body is vena cava (vena cava/venule).
D. Given below are set of four terms each. Identify the odd one in each set and name the category to which the remaining three belong.
=
|
|
The Odd One Out |
Categorisation for the rest of the terms |
|---|---|---|
|
1. Heart, Blood, Blood vessel, Trachea |
Trachea |
Parts of the circulatory system |
|
2. Arteriole, Vein, Artery, Aorta |
Vein |
Parts of Artery |
|
3. RBC, Platelet, Vein, WBC |
Vein |
Components of blood |
|
4. Vena cava, Vein, Artery, Venule |
Artery |
Parts of Vein |
|
5. AB, A, B, RBC |
RBC |
Names of blood group |
E. Briefly mention the main function of each of the fallowing.
For example, ear: hearing;
1. Heart : pumping of blood;
2. Capillaries : exchange of gases, nutrients, and wastes between the blood and the cells in the body.
3. WBCs : defend the body against harmful foreign bodies.
4. Pulmonary vein : carries oxygenated blood.
5. Pulmonary artery : carries deoxygenated blood.
F. Write the exact location of the following.
1. Heart : centre of the chest cavity, pointing slightly to the left.
2. Ventricles : lower chambers of the heart.
3. Aorta : largest artery in the heart.
4. Capillaries : around organs and tissues of the body.
5. Pulmonary semi-lunar valve : pulmonary artery.
Section II
G. Give reason for the following.
1. The RBCs are red in colour.
= The RBCs are red in colour due to the presence of a red-coloured, iron-containing pigment called haemoglobin in RBCs.
2. In human heart, there is no intermixing of the oxygenated and deoxygenated blood.
= In human heart, these is no intermixing of the oxygenated and deoxygenated blood because of the presence of the wall called septum dividing the left side of the heart from the right.
3. Veins have valves at regular intervals.
= Veins have valves at regular intervals to prevent the backflow of blood.
4. The WBCs provide immunity to our body.
= The WBCs provide immunity to our body by producing chemicals called antibodies to destroy harmful foreign bodies.
5. Regular consumption of fatty food can cause heart diseases.
= Regular consumption of fatty food can cause heart disease as it lead to deposition of fats (cholesterol) along the walls of the arteries. This increases the blood pressure and may even cause a heart attack.
H. Differentiate between the following pair of words on the basis of the term mentioned within brackets.
1. Heart and blood vessel. (function)
= Heart pumps the blood but blood vessels comprise a network of hollow tubes present throughout the body through which blood flows.
2. Blood and plasma. (constituent)
= Blood is composed of two components : plasma and blood cells.
About 92% of the volume of plasma is water and the remaining 8% contains dissolved substances such as proteins, glucose, minerals, ions, and hormones.
3. Pulmonary artery and pulmonary vein. (origin)
= Pulmonary artery originates from right ventricle and the pulmonary vein originates from the left atrium.
4. Artery and vein. (condition of wall)
= Artery is thick-walled but vein is thin-walled.
5. RBC and WBC. (shape)
= Mature RBCs are biconcave in shape but WBCs are irregular in shape.
I. Define the following.
1. Pulse.
= Pulse is defined as a pressure wave transmitted through the arteries as the ventricular contraction forces fresh blood into it.
2. Heartbeat.
= One complete contraction and relaxation of the heart makes up a heartbeat.
3. Blood pressure.
= The pressure exerted by blood on the walls of the arteries is called blood pressure.
4. Aorta.
= The largest artery is called aorta. It leaves the left ventricle, carrying oxygenated blood to all parts of the body.
5. Blood vessels.
= Blood vessels comprise a network of hollow tubes present through the body through which blood flows.
J. Short answer questions.
1. Name the three types of blood cells and blood vessels.
= The three types of blood cells are - i) Red Blood Cells or Erythrocytes; ii) White Blood Cells or Leucocytes; and iii) Platelets or Thrombocytes;
The three types of blood vessels are - i) Arteries; ii) Veins; and iii) Capillaries;
2. What are the components of plasma?
= About 92% of the volume of plasma is water and the remaining 8% contains dissolved substances such as proteins, glucose, minerals, ions, and hormones.
3. Name the blood group that is the universal donor and the blood group that is the universal recipient.
= Name the blood group that is the universal donor is O and the blood group that is the universal recipient is AB.
4. Name the blood vessels entering the heart and state their role.
= Two large veins, the superior and inferior vena cava, bring deoxygenated blood from different parts of the body into the right ventricle.
The pulmonary vein brings oxygenated blood from the lungs into the left atrium.
5. Name the blood vessels leaving the heart and state their role.
= The largest artery, called the aorta, leaves the left ventricle, carrying oxygenated blood to all parts of the body.
The pulmonary artery leaves the right ventricle carrying deoxygenated blood to the lungs for oxygenation.
6. What is the function of atrio-ventricular valve in human heart?
= Regulates the flow of blood inside the heart. It ensures that the flow of blood is only in one direction in the heart.
K. Long answer questions.
1. Enumerate the functions of blood.
= Blood is the circulating fluid for transporting the substances such as nutrients, hormones, and oxygen to all the body cells.
It also helps in carrying metabolic wastes like carbon dioxide and urea away from the body cells to the excretory organs so that these can be removed from the body.
2. Give a comparative account of artery, vein and capillary. Also draw their diagrams.
=
|
Arteries |
Veins |
Capillaries |
|---|---|---|
|
Carry blood from the heart to other organs and body parts. |
Carry blood from organs and other body parts to the heart. |
Carry blood from arteries/arterioles to veins/venules. |
|
Generally carry oxygenated blood. |
Generally carry deoxygenated blood. |
Carry both. |
|
Thick, muscular middle layer. |
Thin, slightly muscular middle layer. |
Only one cell thick, muscles are absent. |
|
Do not have valves. |
Have valves. |
Do not have valves. |
Diagram of Artery, Vein and Capillary
3. Draw a neatly labelled diagram of the heart to describe its structure and working.
=
Diagram of Heart
Structure of the heart :- The heart has four chambers.
i) Atria :- Atria are the two thin-walled, upper chambers of the heart. They receive blood from different organs of the body and pump it into the ventricles.
ii) Ventricles :- Ventricles are two thick walled, lower chambers of the heart. These pump the blood received from the atria out of the heart to the different organs to the body. The right atrium and right ventricle together pump the deoxygenated blood. The left atrium and the left ventricle together pump the oxygenated blood.
A wall, called septum, present in the middle of the heart, divides the left side of the heart from the right. It thus prevents the intermixing of the oxygenated and deoxygenated blood.
iii) Blood vessels entering the heart :- Two large veins, the superior and inferior vena cava, bring deoxygenated blood from different parts of the body into the right ventricle.
The pulmonary vein brings oxygenated blood from the lungs into the left atrium.
iv) Blood vessels leaving the heart :- The largest artery, called the aorta, leaves the left ventricle, carrying oxygenated blood to all parts of the body.
The pulmonary artery leaves the right ventricle carrying deoxygenated blood to the lungs for oxygenation.
4. Write a detailed note to describe the process of blood circulation in human body.
= The continuous flow of blood inside the body is termed as blood circulation. There are two types of circulatory pathway involving transport of blood.
❐ A shorter path, called the Pulmonary circulation, transports blood between the heart and the lungs. Deoxygenated blood form the right side of the heart flows into the lungs. From the lungs, the oxygenated blood flows to the left side of the heart.
❐ A longer path, called Systemic circulation, transports blood between the heart and the entire body. Oxygenated blood from the left side of the heart flows to the rest of the body. The deoxygenated blood from the body cells is then returned to the right side of the heart.
5. Describe the effects of increased physical activity on breathing and circulation.
= To perform vigorous exercise, muscles need to work faster. For this, muscle cells must receive more oxygen to produce a higher amount of energy i.e., ATP.
That is why, during vigorous exercise, more oxygen is needed by the muscle cells than when body is at rest. Exercise increases the rate of breathing and also the volume of air that is inhaled and exhaled. This ensures that more oxygen enters the bloodstream and is supplied to the muscle cells quickly.
However due to increased respiration in the muscle cells, more must be expelled quickly from the bloodstream. Therefore, the heart beats faster to pump blood quickly. The volume of blood pumped per unit time also increases. As a result, more oxygen is absorbed into the blood and more carbon dioxide is expelled from it per unit time.
During strenuous exercise, oxygen demand is more and the supply may not be sufficient to meet the needs. Glucose is then broken down by the body in the absence of oxygen, resulting in the absence of oxygen, resulting in the formation of lactic acid in the muscles. The energy released from this breakdown so glucose is much less than what is released in the presence of oxygen. Lactic acid makes muscle tissue acidic, which causes muscle fatigue.
6. Write a note on blood donation.
= A person with blood group O does not possess any antigen and is called a universal donor. This person can donate blood to a person of any blood group.
A person with blood group AB has both the antigens A and B and is called a universal recipient. Such a person can receive blood from a person of any blood group.