NCERT Solutions for Class 11 Biology Chapter 18
NCERT Solutions for Class 11 Biology Chapter 18 Body Fluids and Circulation in PDF format to Free Download or Study online without downloading the files for academic session 2020-2021.Download NCERT Solutions for other subjects for UP Board, MP Board, CBSE and other boards also using using NCERT Books. Visit to Discussion Forum and join the world of knowledge.
NCERT Solutions for Class 11 Biology Chapter 18
|Chapter 18:||Body Fluids and Circulation|
Class 11 Biology Chapter 18 Solutions in English
NCERT Solutions for Class 11 Biology Chapter 18 in PDF form to free download is given below. Download NCERT Books 2020-21 for new academic session following the latest CBSE Syllabus. Offline Apps and NCERT Solutions are helpful for NIOS students also. Explore the your knowledge through discussion forum and help the other students replying their questions.
Important Notes on Body Fluids and Circulation
1. Cardiac output: The amount of blood pumped by heart per minute is called cardiac or heart output. The value of cardiac output of a normal person is about 72 × 70 = 5040 mL or about 5L per minutes.
2. Electrocardiograph (ECG): The machine used to record electrocardiogram.
3. Electrocardiogram ECG: The graphic record of the electric current produced by the excitation of the cardiac muscles. It is composed of a ‘P’ wave, ‘QRS’ wave. (Complex) and ‘T’ wave.
1. A special connective tissue that circulates in principal vascular system of man and other vertebrates consisting of fluid matrix, plasma and formed elements.
2. Blood Pressure: The resistance offered by the lumen of the artery to the flow of Blood.
Cardiac Cycle: The rhythmic contraction and dilation of different parts of heart in one beat.
3. Hypertension: The condition when blood pressure is higher than normal (120/80 mmHg)
4. Systole: Contraction of heart muscles.
5. Diastole: Relaxation of heart muscles.
1. The liquid part of blood or lymph which is straw coloured, viscous fluid and contains (only lymbphocytes) about 90-92% of water and 6-8% proteins.
2. Lymph: A clear yellowish, slightly alkaline, coagulable fluid, containing white blood cells in a liquid resembling blood plasma.
3. Serum: Blood plasma from which fibrinogen and other clotting factors have been removed.
4. Heart Beat: The rhythmic contraction and relaxation of the heart, which includes one systole (contraction phase) and one diastole (relaxation phase) of the heart. Heart beat count of healthy person is 72 times per minute.
1. The colourless mobile fluid connective tissue drains into the lymphatic capillaries from the intercellular spaces. It is formed by squeezing of blood through capillaries, within tissues. Its ¯ow is unidirectional i.e., from tissues to heart.
2. It is composed of fluid matrix, plasma, white blood corpuscles or leucocytes.
i). It drains excess tissue from extra cellular spaces back into the blood,
ii). It contain lymphocytes and antibodies.
iii). It transport digested fats.
Important Questions on 11th Biology Chapter 18
They are the most abundant cells and contain the red pigment called haemoglobin. They carry oxygen to all parts of the body. Red blood cells are produced continuously in some parts of the body such as the marrow of long bones, ribs, etc. There are about 4 – 6 million RBCs per cubic millimetre of blood.
Leucocytes are colourless cells. These cells do not contain haemoglobin. They are the largest cells of the body and are divided into two main categories.
These leucocytes have granules in their cytoplasm and include neutrophils, eosinophils, and basophiles. Neutrophils are phagocytic cells that protect the body against various infecting agents. Eosinophils are associated with allergic reactions, while basophiles are involved in inflammatory responses.
Lymphocytes and monocytes are agranulocytes. Lymphocytes generate immune responses against infecting agents, while monocytes are phagocytic in nature.
Platelets are small irregular bodies present in blood. They contain essential chemicals that help in clotting. The main function of platelets is to promote clotting.
Globulin is a major protein of the plasma. It protects the body against infecting agents.
Albumin is a major protein of the plasma. It helps in maintaining the fluid volume within the vascular space.
Like the other connective tissues, blood is mesodermal in origin.
It connects the body systems, transports oxygen and nutrients to all the parts of the body, and removes the waste products. Blood has an extra-cellular matrix called plasma, with red blood cells, white blood cells, and platelets floating in it.
The movement of blood in an organism is divided into two parts:
Systemic circulation involves the movement of oxygenated blood from the left ventricle of the heart to the aorta. It is then carried by blood through a network of arteries, arterioles, and capillaries to the tissues. From the tissues, the deoxygenated blood is collected by the venules, veins, and vena cava, and is emptied into the left auricle.
Pulmonary circulation involves the movement of deoxygenated blood from the right ventricle to the pulmonary artery, which then carries blood to the lungs for oxygenation. From the lungs, the oxygenated blood is carried by the pulmonary veins into the left atrium.
Hence, in double circulation, blood has to pass alternately through the lungs and the tissues.
Significance of double circulation:
The separation of oxygenated and deoxygenated blood allows a more efficient supply of oxygen to the body cells. Blood is circulated to the body tissues through systemic circulation and to the lungs through pulmonary circulation.
Cardiac output is defined as the amount of blood pumped out by the ventricles in a minute.
These sounds provide important information about the condition and working of the heart.