NCERT Solutions for Class 11 Biology Chapter 18

NCERT Solutions for Class 11 Biology Chapter 18 by Extramarks are detailed and step-by-step solutions prepared by subject matter experts. Students can use these solutions to find accurate answers to the questions given at the end of NCERT Class 11 Biology Chapter 18.

To make the best use of these solutions, students should ideally go through the chapter at least once, attempt textbook questions on their own, and then cross verify using these resources. NCERT Solutions for Class 11 Biology Chapter 18 can also be very useful for last-minute preparations.

NCERT Solutions for Class 11 Biology Chapter 18 – Body Fluids and Circulation

Access NCERT Solutions for Class 11 Biology Chapter 18 – Body Fluids and Circulation 

NCERT Solutions for Class 11 Biology Body Fluids and Circulation 

In Biology Class 11 Chapter 18, students will learn about body fluids and their functions of circulating necessary nutrients and substances within the body. The chapter talks in detail about blood circulation, the different functions of blood, its composition, and the entire process of blood circulation inside the body including pulmonary and systemic circulatory pathways.

Students can access the NCERT Solutions for Class 11 Biology Body Fluids and Circulation here and prepare better for their examinations.

NCERT Solutions for Chapter 18 Class 11 Biology – Body Fluids and Circulation

Body Fluids and Circulation Chapter in NCERT Solutions for Chapter 18 Biology Class 11 falls under Unit V, Human Physiology. This particular chapter teaches students about the concepts related to blood circulation and the characteristics of tissue fluids (blood and lymph). Other major topics discussed in this chapter include double circulation, cardiac process regulation, pathways relating to circulation, disorders of cardiac activity, plasma, the entire human circulatory system, blood groups, ECG, and more.

Chapter 18 Biology Class 11 will teach students about the circulatory structural differences in the types of organisms, depending on the level of physical and mental complexity of the animal. The chapter also discusses the health of the heart, blood transfusions, number of blood particles; health and unhealthy habits that will affect the health of your heart. 

NCERT Solutions for Class 11 Chapter 18 – Marks Distribution

Chapter 18 Biology Class 11 NCERT Solutions comes under Unit 5 of the CBSE Class 11 Biology. The entire unit carries a total of 18 marks in the examinations. In the NEET exam, this chapter has a 20% topic weightage of the total grade. 

Students should know the topics covered in this chapter and master them. The main topics covered in this chapter are:

  • Blood
  • Plasma
  • Blood Groups
  • Element Formation
  • Blood Coagulation
  • Tissue Fluids 
  • The Circulatory system in Humans
  • The cardiac Cycle 
  • Electrocardiograph
  • Double Circulation
  • Disorders concerning Circulation
  • Cardiac activity and its Regulation

Benefits for NCERT Solutions for Class 11 Biology Chapter 18 – Body Fluids and Circulation

It is important for students to study the entire chapter and solve the questions not just for comprehensive learning, but also to do well in their exams. The benefits of including NCERT Solutions for Class 11 Biology Chapter 18 in one’s preparation are as follows:  

  • NCERT Solutions for Class 11 Biology Chapter 18 provide complete answers to all the textbook questions covered under Chapter 18.
  • The solutions are written in a simple language
  • Since these solutions are drafted by experts, students can use these to get an idea of how they should write their answers in final exams, how long or detailed the answers need to be, and what exactly an evaluator considers a good answer.

Related Questions 

  1. Mention the names of any eight common diseases, their causative agents, symptoms, and prevention measures. 
  2. Why do cancer cells lack contact inhibition?
  3. Are T cells innate or adaptive?
  4. Name one medical technique which is based on magnesium produced in the human body and for what purpose is this technique used?
  5. What is the difference between vaccines and medicines?
  6. Which is an example of anaerobic exercise?
  7. What are the symptoms of a weak heart?
  8. What is the first sign of hypoxia?
  9. Which one of the following is responsible for blue baby syndrome?
  1. Fluoride 
  2. Nitrate 
  3. Arsenic
  4. Lead

FAQs (Frequently Asked Questions)

Plasma proteins include Globulins, Albumins, and Fibrinogens. Globulins that assist in the defence mechanism in the body are called immunoglobulins. The osmotic balance of the body is maintained by albumin. Fibrinogens help to maintain blood coagulation.

Erythrocytes are also known as red blood cells (RBCs). They carry oxygen and haemoglobin throughout the body. The haemoglobin reacts with oxygen and forms oxyhaemoglobin. 

Leukocytes are the white blood cells that kill germs. Neutrophils act as a defence mechanism for the bacteria called phagocytosis. Thrombocytes help in the coagulation of blood. 

The important topics of NCERT Solutions for Class 11 Biology Chapter 18 – Body fluids and Circulation are:

  • Components and elements in the blood
  • Plasma proteins
  • Blood as connective tissue
  • The difference between lymph and the blood, open and closed system of circulation
  • Systole and Diastole
  • P-wave
  • T-wave and cardiac cycle
  • Atrioventricular node
  • Atrial-lenticular bundle

There are numerous advantages to using NCERT Class 11 Biology Chapter 18 – Fluids and circulation. The questions and answers given are clear and precise. All of the answers follow a systematic method of answering the question. Students can follow the same and work on their answers to provide concise, relevant, and well-structured content. Extramarks’ subject experts adhere to CBSE guidelines, ensuring that these solutions are accurate and reliable.

Blood is known to be a connective tissue as it is mesodermally inferred and contains an extra cell lattice known as plasma. It is abundant and widely dispersed throughout the body. Connective tissues can provide specific connections and ties between different organs, assisting different organs of the body and subsequently moving oxygen and other supplements inside the body, removing waste from the body, and flowing throughout the body. Henceforth, it is called connective tissue. 

Contraction of the heart happens due to a uniquely adjusted heart muscle known as the sinoatrial node which is situated in the right atrium. The characteristic feature of this node is in producing a rush of compression and controlling the heartbeat. Hence, it is known as the pacemaker. Since the heartbeat is started by the SA node and the motivation to withdraw begins in the heart itself, the human heart is known to be myogenic. The hearts of vertebrates and molluscs are also myogenic. 

It is the process in which blood passes through the heart twice in one complete cycle. The process involves two types of blood circulations;

  1. Systemic circulation – In this circulation, the flow of the oxygenated blood takes place from the left ventricle of the heart to the aorta. Then a network of arteries, arterioles, and capillaries supply this oxygenated blood to the various tissues in the body. From the tissues, the deoxygenated blood is carried by the veins, venules, and vena cava, and is emptied in the right atrium.
  2. Pulmonary Circulation – This circulation is the flow of the deoxygenated blood from the right ventricle to the pulmonary artery, which then carries the blood to the lungs to get oxygenated. Then the oxygenated blood from the lungs is carried by the pulmonary veins to the left atrium.  

The significance of double circulation is that complete separation of oxygenated and deoxygenated blood takes place which allows a more efficient supply of oxygen to the cells in the body.