IGCSE Biology Transport in Animals Past Paper 2024 PDF

BY CELL :00201110983031 00201110983031 [email protected]  List the components of blood as: red blood cells, white blood cells, platelets and plasma Desc...

BY CELL :00201110983031 00201110983031 [email protected]  List the components of blood as: red blood cells, white blood cells, platelets and plasma Describe the circulatory system as a system of 2 Identify red and white blood cells in blood vessels with a pump and valves to ensure photomicrographs and diagrams one-way flow of blood 3 State the functions of the following components Identify in diagrams and images the structures of of blood: the mammalian heart, limited to: muscular wall, (a) red blood cells in transporting oxygen, septum, left and right ventricles, left and right including the role of haemoglobin atria, one-way valves and coronary arteries (b) white blood cells in phagocytosis and antibody production 2 State that blood is pumped away from the heart (c) platelets in clotting (details are not required) in arteries and returns to the heart in veins (d) plasma in the transport of blood cells, ions, 3 State that the activity of the heart may be nutrients, urea, hormones and carbon dioxide monitored by: ECG, pulse rate and listening to 4 State the roles of blood clotting as preventing sounds of valves closing blood loss and the entry of pathogens 4 Investigate and describe the effect of physical activity on the heart rate Describe the single circulation of a fish 5 Describe coronary heart disease in terms of 3 Describe the double circulation of a mammal the blockage of coronary arteries and state 4 Explain the advantages of a double circulation the possible risk factors including: diet, lack of Identify in diagrams and images the exercise, stress, smoking, genetic predisposition, atrioventricular and semilunar valves in the age and sex mammalian heart 6 Discuss the roles of diet and exercise in reducing 8 Explain the relative thickness of: the risk of coronary heart disease (a) the muscle walls of the left and right Describe the structure of arteries, veins and ventricles capillaries, limited to: relative thickness of wall, (b) the muscle walls of the atria compared to diameter of the lumen and the presence of valves those of the ventricles in veins 9 Explain the importance of the septum in 2 State the functions of capillaries separating oxygenated and deoxygenated blood 3 Identify in diagrams and images the main blood 10 Describe the functioning of the heart in terms vessels to and from the: of the contraction of muscles of the atria and (a) heart, limited to: vena cava, aorta, pulmonary ventricles and the action of the valves artery and pulmonary vein (b) lungs, limited to: pulmonary artery and CELL :00201110983031 00201110983031 [email protected] Consists of 1. Heart 2. Blood Vessels 3. Blood The heart Is a muscular pump made of cardiac muscles which is a strong type of muscle that helps keep the heart contracting without stopping. The function of the heart pump blood all around the body to: 1- Supply different cells with the required nutrients and oxygen. 2-And to remove carbon dioxide and other waste products from cells to The activity of the heart 1. May be monitored by ECG. 2.Pulse rate and listening to sounds of valves closing. The rhythmic sounds made by the heart Lob: due to closure of the two valves between arteries and ventricles. Dup: due to closure of the semi-lunar values in the aorta and pulmonary artery The heart beats: Is the ripple of pressure which passes down on an artery due to heart beats The rate of pulse represents the rate of heart beats. Blood pressure: It is the pressure created in arteries due to the flow of blood during heart beats. It is measured by an apparatus known as sphygmomanometer CELL :00201110983031 00201110983031 [email protected]  The normal blood pressure is 120/80 mm/Hg. systolic pressure, it is the pressure during contraction of the ventricles (120 ). diastolic pressure, it is the blood pressure during relaxation of the ventricles (80 ). How to measure pulse 1.Use the first two fingers of your right hand and lie them on the inside of your left wrist, 2.feel the tendon near the outside of your wrist, then you can feel the artery in your wrist pulsing your heart pumps blood through it. 3.Count the number of pulses per minute. 4.Repeat this step and take the average for accuracy. CELL :00201110983031 00201110983031 [email protected] Component Adaptation Figure 4 2 Upper thin walled CHAMBERS chambers (Atria) 2 lowered thick walled Chambers. (ventricles); To be stronger and pump the blood with greater pressure to all the body parts. VALVES 1. Atrioventricular between ventricles and arteries (aorta and pulmonary arteries) 2. Semi lunar between the arteries and the heart They prevent the back flow of blood to flow in one direction. - Blood coming from atria them to open - Flaps float over blood to close the opening - The tendons prevent them from being Turned back towards atria CELL :00201110983031 00201110983031 [email protected]  - The flaps of semi-lunar valves act as pockets. - When blood tries to flow back the pockets. Become filled with blood and close. No semi-lunar valves in arteries except at their beginning As blood is not liable to flow back due to the high blood pressure in them. SEPTUM Separates the oxygenated blood in the left heart side from deoxygenated blood in the right heart side. CORONARY These are blood vessels which supply ARTERIES blood to heart muscle, as they need a constant supply of nutrients& 02, used in respiration to release energy needed for contraction& relaxation. Narrowing or Blockage of coronary arteries leading to heart Attack. 1-Smoking (nicotine) which increases blood pressure. 2- diet high in salt, saturated fats 'or cholesterol. 3- Obesity due to lack of exercising. CELL :00201110983031 00201110983031 [email protected]  4- Stress over long period of time. 5- genes. 1. IMPROVING LIFE STYLE BY A-Exercising which Prevents weight gain that Lowers blood pressure. B- stop smoking. C- diet with less saturated fats & salt. 2. DRUGS Statins: can lower cholesterol. 2. Anti-hypertensive drugs that helps lower the blood pressure. · ~ 3. Aspirin that reduces risk of blood clots formation inside blood 3. SURGERY TREATMENT A. BYPASS: if the coronary arteries are blocked a coronary artery bypass operation may be carried out. In which the damaged coronary artery can be replaced with a length of blood vessels taken from another part of the body. (vein) CELL :00201110983031 00201110983031 [email protected]  B. ANGIOPLASTY If the coronary artery is narrowed, angioplasty can help expand this artery. Where non-inflated balloon ( stent) is passed into a narrowed artery, and then the balloon is inflated using water. This pushes the artery open. The balloon is then removed leaving a metal cage (stent) to keep the artery open allowing flow of blood. THE BLOOD CIRCULATION PULMONARY CIRCULATION SYSTEMIC CIRCULATION it starts from right ventricle pumping it starts from Left ventricle pumping deoxygenated blood out of heart to lungs oxygenated blood out of heart to body and returning into left atrium as oxygenated and returning into right atrium as blood. deoxygenated blood Types of blood circulation Single Double It means that the blood pass through the It means that the blood pass through the heart once in one complete blood heart twice in one complete blood circulation circulation. Ex fish ex-human, birds and reptiles. 1-because when the blood enters the lung, it loses some pressure given to the blood by pumping heart so it enters the heart again to raise its pressure before being delivered in.to the body. CELL :00201110983031 00201110983031 [email protected]  2-to prevent damage of the delicate capillaries in the lung. CHANGING THE HEART RATES ACCORDING TO THE PHYSICAL ACTIVITY INCREASING DECREASING 1. During exercise 1.during sleeping of relaxation as the energy 2. Happiness needed by the body during this period is 3. Production of adrenaline. low. 2.Sadness. WHY The normal heart beats of players and those who carry out regular exercise are less than the other people. a. Their heart muscles becomes stronger, able to perform the required functions with lower number of beats b. Volume of the heart chambers increases therefore their stroke volume (the amount of blood pumped in one heart beat ) becomes greater. CELL :00201110983031 00201110983031 [email protected]  The blood circulation Stage Diastole Atrial systole Ventricular systole Atrium Relaxes contracts relaxes Ventricle Relaxes Relaxes Contracts Atrioventricular open opens the pressure Closed in atrium is greater them that in ventricle, so it opens preventing the back flow of blood Semi lunar Closed closed opened CELL :00201110983031 00201110983031 [email protected] Heart is formed of cardiac muscle which has a pacemaker (in the right atrium), which send electrical signals through walls of the heart at regular intervals to make the heart muscle contract. 2-Heart has septum separating it into 2 parts (left& right). 3-Ventricles contract increasing pressure on blood to be pumped out of heart where: a)-Right ventricle: has thinner walls, so lower pressure to pump blood only to lungs. b)-Left ventricle has thicker walls, so higher pressure to pump blood to hole whole body. 1. Supply active muscles with oxygen and glucose to respire at a higher rate and produce more energy needed for muscle contraction. 1.Exercising causes an increase-in production of carbon dioxide (weak acid) from high rate of respiration, 2.The pH of blood will be decreased. 3. The brain detects this change in pH, sending more frequent impulses to pacemaker, increasing heart rate 2.The blood vessels Arteries Capillaries Veins 1.Carry blood away from on 1.Exchange of substances Carry blood to heart to the tissues. between from heart from 2-Carry oxygenated blood blood& cells. the tissues. except for the pulmonary a) diffusion of gases Carry artery. (C02& 02) deoxygenated 3.High pressure b)- allows reabsorption blood except for 4. thick wall withstand high of useful substances back the pulmonary Function pressure. to blood. vein. And 5. Narrow lumen to maintain C) pores Allow passage of 3. low pressure in adaptati high pressure. WBCs to tissue fluid. order not to resist on Adaptation the blood flow. 1. Have fine gaps between 4.thin wall. cells to allow exchange of 5. Narrow lumen materials 6. contains semilunar valves to CELL :00201110983031 00201110983031 [email protected]  2. Large in number to prevent back flow increase the surface area of blood. of exchange of materials between blood and body tissues Blood vessels in the human body CELL :00201110983031 00201110983031 [email protected]  3.THE BLOOD Consists of 1. PLASMA 2. BLOOD CELLS 1. Plasma Forms 55% of blood, yellowish fluid formed of: A-90%water Which is an important solvent at which all substances are dissolved to be transported to different parts of body. B-10% dissolved Organic substances such as Glucose, amino acids, minerals, hormones, C02, urea. function Transport of blood cells, plasma proteins, hemoglobin, enzymes, antibodies), soluble nutrients (glucose, amino acids, minerals), waste products ( urea, Co2) 2. THE BLOOD CELLS A- white blood cells 1. They have nucleus, can squeeze out of blood through walls of blood capillaries into all parts of body. , 2. They fight pathogens (disease causing bacteria& viruses) Place of formation : Bone Marrow Types of white blood cells Lymphocytes Phagocytes Release antibody which has the following Ingest and Engulf the pathogens to be function digested by the enzymes. 1.clump the pathogens. 2.kill the pathogens. 3.agregate the pathogens. 4-Stop bacteria from moving.  Contains only one large nucleus CELL :00201110983031 00201110983031 [email protected] B-Red blood cells Function 1- Transport of O2 2- Transport of small amount of Carbon Dioxide Place of formation : Bone Marrow Adaptation of Red Blood Cells 1. Very small and flexible to be able to squeeze through the fine capillaries. 2. Have elastic walls to squeeze themselves in the fine capillaries. 3. Contain haemoglobin Which picks up oxygen at Lungs and let go of it at all body tissues. 4. Biconcave to increase surface area to speed up the rate of diffusion of oxygen. 5. Contain no nucleus to carry more haemoglobin to transport more oxygen. 6. Produces in very high rate, because they have short life (about 120 days). C. Platelets Small fragments of cells with no nucleus, that help in blood clotting. Importance of blood clotting reducing loss of blood& entry of pathogens through cut. 1. Blood vessels are damaged and blood is exposed to air. 2. Platelets stimulates clotting where; - An enzyme (thrombin) is released. - Calcium ions, vitamin K and others blood clotting factors must be present. 3. Soluble fibrinogen (plasma protein) turned by thrombin enzyme into insoluble fibrin. 4. Fibrin forms a mesh of fibres to trap blood cells, and platelets stick together. 5. Then they dry out forming a scab preventing blood loss and entry of pathogens. CELL :00201110983031 00201110983031 [email protected]