NEET -BIOLOGY-CHAPTER 16-DIGESTION AND ABSORPTION-QUICK REVISION

CHAPTER 18 BODY FLUID AND CIRCULATION • Blood is a special connective tissue consisting of a fluid matrix, plasma, and formed elements. • Plasma is a straw coloured, viscous fluid constituting nearly 55 per cent of the blood. 90-92 per cent of plasma is water and proteins contribute 6-8 per cent of it. Fibrinogen, globulins and albumins are the major proteins. Fibrinogens are needed for clotting or coagulation of blood. Globulins primarly are involved in defense mechanisms of the body and the albumins help in osmotic balance. Plasma also contains small amounts of minerals like Na+, Ca++, Mg++, HCO3 – , Cl– , etc. Glucose, amino acids, lipids, etc., are also present in the plasma as they are always in transit in the body. Factors for coagulation or clotting of blood are also present in the plasma in an inactive form. Plasma without the clotting factors is called serum. • Erythrocytes, leucocytes and platelets are collectively called formed elements and they constitute nearly 45 per cen...

CHAPTER 17 BREATHING AND EXCHANGE OF GASES • Lower invertebrates like sponges, coelenterates, flatworms, etc., exchange O2 with CO2 by simple diffusion over their entire body surface. • Earthworms use their moist cuticle and insects have a network of tubes (tracheal tubes) to transport atmospheric air within the body. • Special vascularised structures called gills are used by most of the aquatic arthropods and molluscs whereas vascularised bags called lungs are used by the terrestrial forms for the exchange of gases. • Larynx in human is a cartilaginous box which helps in sound production and hence called the sound box. • Lungs are covered by a double layered pleura, with pleural fluid between them. • Inspiration can occur if the pressure within the lungs (intra-pulmonary pressure) is less than the atmospheric pressure, i.e., there is a negative pressure in the lungs with respect to atmospheric pressure. • Similarly, expiration takes place when the intra-pulmonary pressure is higher t...

• Name of the Italian scientist who began his scientific career studying the cardiovascular systems of reptiles. Later , he turned his attention to the mammalian auditory systems- It was ALFONSO CORTI. • LIST OF Important Vitamins and Scientific names- Vitamin A : RETINOL, Vitamin B1 : Thiamine, Vitamin B2: Riboflavine, Vitamin B5 : Pantothenic Acid, Vitamin B6: Pyridoxine, Vitamin B3: Niacin or Nicotinic Acid, Vitamin B7: Biotin, Vitamin B9: Folic acid, Vitamin B12: Cobalamin, Vitamin C : Ascorbic acid, Vitamin D : Calciferol, Vitamin E : Tocopherol, Vitamin K : Phytomenadione. • Each tooth is embedded in a socket of jaw bone . This type of attachment is called thecodont. • The tongue is a freely movable muscular organ attached to the floor of the oral cavity by the frenulum. • The upper surface of the tongue has small projections called papillae, some of which bear taste buds. • pharynx which serves as a common passage for food and air. • Structure of stomach is J shaped. • A mu...