Selina Concise Class 8 Biology Solution Chapter No. 6- ‘The Circulatory System’ For ICSE Board Students.
Selina Concise Biology Solutions for Class 8th Chapter 6 The Circulatory System with easy language, expert answers and doubt clearing sections. The book is especially designed keeping in mind the syllabus of ICSE board and the difficulty level faced by the students of ICSE boards class 8.
Selina Class 8 Biology Chapter 6 Solution:
Multiple choice questions
1.) Put a tick mark against the correct alternative in the following statements:
(a) The vein which brings oxygenated blood to the heart from lungs :
(i) Renal vein (ii) Superior vena cava (iii) Pulmonary vein (iv) Coronary vein
Answer: Answer is(iii) Pulmonary vein, because the vein present between the heart and lungs is Pulmonary vein
(b) The path which the blood flows through during pulmonary circulation is :
(i) RA RV Pulmonary arteries Lungs Pulmonary veins LA
(ii) LA LV Pulmonary veins Lungs Pulmonary artery RA
(iii) LA LV Aorta Body Vena cavae RA
(iv) RA RV Vena cavae body Aorta LA
Answer: Answer is (i) RA RV Pulmonary arteries Lungs Pulmonary veins LA
The vein carries the oxygenated blood to the heart then enters into right artrium and goes to right ventricle then this oxygenated blood by pulmonary arteries enters into lungs and then goes to left atrium and left ventricle.
Short Answer Question :
1) In which organ of our body does blood get oxygenated ?
Answer: Right part of the heart contains oxygenated blood it comes from the organ lungs.
2) Which side of the heart (Left or right) contains oxygenated blood ?
Answer: Right part of the heart contains oxygenated blood
3) Name the following :
(a) Three kinds of blood vessels: Capillary, vein and artery.
(b) Two types of blood circulation in the human body : Systemic circulation and pulmonary circulation
(c) The membranous structure which divides the heart into right and a left portion : It is septum.
(d) The structure responsible for starting electrical impulses that cause the heart to contract and relax in order to keep pumping blood : SA node, also called as pacemaker.
(e) The scientist who identified different types of blood group : Karl Landsteiner
4) Define the terms :
(a) Circulatory system : Circulatory system mainly made up of heart, blood and blood vessels. It circulates the blood throughout the body and provides oxygenated blood to all parts of the body.
(b) Blood: It can be defined as fluid connective tissue which contains plasma and cells. It circulates all over the body.
(c) Lymph: It is a colorless fluid, circulating through lymphatic system by the lymphatic vessels.
(d) Artificial pacemaker :This is a one kind of device used in case of heart patients to maintain the heart rate.
Long Answer Question :
1) Differentiate between the following pairs on the basis of what is indicated in the brackets.
(a) Pulmonary artery and pulmonary vein (Kind of blood)
Answer:
Pulmonary artery | pulmonary vein |
Transports the deoxygenated blood. | Transports the oxygenated blood. |
(b) Artery and vein (Direction of blood flow)
Answer:
Artery | Vein |
Carry the blood away from heart | Carries the blood towards heart. |
(c) Closed and open vascular system (definition)
Answer:
Closedvascular system | open vascular system |
In this blood flows through blood vessels. | Blood not flows through blood vessels. |
(d) Bicuspid and tricuspid valve (Location)
Answer:
Bicuspid valve | tricuspid valve |
Present on left side between left atrium and left ventricle. | Present on right side between right atrium and right ventricle. |
(e) Blood and lymph (composition)
Blood | Lymph |
Blood contains plasma and cells. | Lymph contains plasma and less number of cells. |
2) Write important role / roles of each.
(a) Pericardial fluid
Answer: Pericardial fluid is present surrounding the heart pericardial layer. It protects the heart from injury and mechanical damage. It also act as softening agent or as lubricant.
(b) Aorta
Answer: Aorta is considered as largest artery present in the body. It transports the oxygenated blood from heart to all the body parts.
(c) Vena cava
Answer: Vena cava is the largest vein present in the body, which is divided into 2 parts such as superior vena cava and inferior vena cava. They carries blood to the heart.
3) Name any four heart related condition that occur normally in human. Briefly explain the cause and symptoms of each of them.
Answer: four heart related condition that occur normally in human are hypertension, heart attack, cardiac arrest and palpitation.
(a) hypertension : It causes due to high blood pressure and high force of blood on blood vessels. The symptoms are blood vessels get damage, increase in blood pressure and more risk of heart attack.
(b) heart attack : It occurs when there is immediate stop of blood supply to the heart due to presence of any blood clot. The symptoms present in heart attack are chest pain, sweating, nausea and shortness of breathing.
(c) cardiac arrest: The cardiac arrest caused due to lack of oxygen in body, any obstruction in the path of blood flow and can be due to excess exercise in the gym. Symptoms include in cardiac arrest are chest pain, nausea, sweating, loss of consciousness.
(d) Palpitation : It can be caused due to tension, depression and anxiety. It can be regarded as initial stage of heart failure where symptoms can be chest pain, dizziness, nausea.
4) Give the function of lymph.
Answer: There are 4 main functions of lymph such as (a) Absorption : The fats present in the body absorbed by lymphatic vessels. (b) Protection : Lymph protects the body from invading pathogens as it contains WBC’s which play role for eliminating pathogens from the body. (c) Nutrition : Gives nutrition to the all parts of the body. (d) Drainage : Un-necessary fluid removes from the body.
5) Explain : (a) Universal donor (b) Universal acceptor
Answer:
(a) Universal donor: It is the term used for blood donation process. There are 8 blood groups present in humans. Out of these eight blood groups the O+ blood person can donate to all the different types of blood, with no reaction in the body. So, Universal donor is the person which having O+ blood group and can donate blood to any person with no side effects.
(b) Universal acceptor: The person with AB+ blood group are called as Universal acceptor, so it can receive the blood from any person with no side effect on the body. Such person called as Universal acceptor
6) During surgical operations or during accidents, the patients may be given blood from outside to save his life. What is the technical name of this process ? Briefly explain the precautions to be observed and taken in this process ?
Answer: During surgical operations or during accidents, the patients may be given blood from outside to save his life. The technical name of this process is blood donation and blood compatibility. Precautions taken during this process are : (a) Identification of donor and recipient blood. (b) The blood should be same of both donor and recipient. (c) To test the blood of donor for any type of infection. (d) After blood donation the recipient must be kept under observation for some period of time to observe any side effect.
7) Given along side is the diagram of the human heart showing its internal structure. Label the parts marked 1 to 6, 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 deoxygenated blood from the body ?
Answer: 1. Left pulmonary artery 2. Superior vena cava 3. Left pulmonary vein 4. Right auricle 5. Left auricle 6. Left ventricle
(a) Deoxygenated blood is carried by the blood vessel marked 2
(b) Aorta is the main artery which takes the blood from heart to different parts of the body.
(c) Right atrium of the heart receives deoxygenated blood from the body