Welcome to your Edexcel AS Biology 3 What is the advantage of a respiratory surface being moistened by mucus? Pressure is reduced. The flow of blood is increased. Exchange of substances other than oxygen can take place. Oxygen can dissolve easily.Which of the following is an adaptation of a respiratory surface for efficient gas exchange? Presence of a thick wall Dry surface area Impermeable for respiratory gases High area to volume ratioWhich of the following is not a function of the lymphatic system? It absorbs and transports fatty acids and fats as chyle from the digestive system. Responsible for the removal of interstitial fluid from tissues. Linking the nervous and endocrine systems by way of the pituitary gland. Transportation of white blood cells to and from the lymph nodes into the bones.The amount of air which passes in or out of the lungs during each cycle of quiet breathing. Inspiratory reserve volume Tidal volume Expiratory reserve volume Vital capacityThe _______ has the thickest wall for pumping blood to the _______. Right auricle, systemic circuit Left ventricle, systemic circuit Left auricle, lungs Right ventricle, lungsSinger and Nicolson's hypothesis for membrane structure. Interpolation theory Cell theory Fluid mosaic model Double helix modelVessels carrying blood away from the heart. Capillaries Veins Arteries TubulesHow does the oxygen move from the lungs into the blood stream? Veins Nerve fibres Small blood vessels A large arterySelect the correct statement/s from the following.a) Human heart is a hollow muscular organb) It is a major component of human circulatory system.c) It is about the size of it's owner's fist.d) It consists of 2 layers. a, c & d a & b only a, b & c AllWhich is not a main component of cigarette smoke? Nicotine Arsenic Carbon Monoxide TarSelect the incorrect statement regarding the system of trachea in insects. It is a highly branched tubular system. It opens to the exterior through spiracles. The air is taken directly upto the cells. Gaseous exchange is not very efficient.Which of the following statement is correct regarding the location of human heart? It is situated more towards the left side from the midline. It is situated right in front of the sternum. It is situated right beneath the thoracic cavity. It is situated more towards the right side from the midline.What is the function of pericardial fluid? Increases blood flow to the heart Reduction of friction when the heart beats Reduction of pressure when the heart beats Controls the heart beatWhat are the 3 layers of a heart?a) Endocardiumb) Epicardiumc) Pericardiumd) Myocardium a, d & b a, d & c c, b & d a, b & cThe function of lymph nodes. Aids in the proper functioning of the immune system. Acts as an endocrine gland. Regulation of electrolytes in the body. Regulates the blood glucose level in the body.The body structure which protects the lungs from physical harm. Bronchus Cartilage Rib cage DiaphragmWhich layer of the heart secretes the pericardial fluid? Pericardium Endocardium Myocardium EpicardiumSelect the correct sequence of steps regarding inspiration.a) Air pressure in the lungs decreases.b) Air flows into the lungs.c) Volume of the lungs increases.d) Diaphragm muscles contract. d, c, a, b d, a, c, b c, a, d, b a, c, b, dFrom which chamber does the freshly oxygenated blood enter the heart? Right ventricle Left ventricle Right auricle Left auricleSelect the correct sequence of steps which shows the movement of oxygen through an insect.a) Spiracle closes.b) Oxygen is delivered directly to respiring tissues.c) Oxygen diffuses through the trachea into the tracheoles.d) Oxygen enters the insect through spiracles and into the trachea. a, d, c, b d, b, a, c d, a, c, b b, a, c, dTime is Up!