HSC Biology Year 2016 Mark 93.00 Pages 46 Published Jan 18, 2017 Biology Notes By James (99.05 ATAR)
Powered by TCPDF (www.tcpdf.org) Your notes author, James. James achieved an ATAR of 99.05 in 2016 while attending The King's School Currently studying at The University of Sydney James says: ATAR 99.05 Subjects Studied - Economics - English Advanced - Biology - Modern History - History Extension - Advanced Maths - Extension I Maths
Identify some responses of plants to temperature changes High Temperatures Evaporative Cooling/Transpiration - When stomata is open, water can evaporate, reducing temperature Reflective Leaf Surface - Waxy Cuticle, shiny leaves reflect heat Reduced Surfaced Area - reducing heat intake Leaf Orientation - hang vertically to reduce exposed surface area Leaf Fall - lose their leaves during colder months to reduce water loss Re-seeding after fire - Eucalypts have buds underneath bark that sprout when exposed to heat Cold Temperatures Low to ground - protect from winds and absorb heat from ground Dormancy - lose leaves in winter, storing heat, water Vernalisation - flower in response to cold temperatures (tulips) Growing in crevices (Saxafrage) protection from elements Identify the form(s) in which each of the following is carried in mammalian blood; Carbon Dioxide, salts, oxygen, lipids, water, nitrogenous wastes and other products of digestion. SUBSTANCE FORM(S) IN WHICH IT IS CARRIED IN MAMMALIAN BLOOD
Dissolved in blood plasma CARBON DIOXIDE (CO 2 ) Bind to haemoglobin. Forming carbaminohaemoglobin. Hydrogen carbonate ions. (HCO 3 ) OXYGEN (O 2 ) WATER (H 2 O) SALTS Oxygen is carried by haemoglobin in red blood cells. Dissolved in blood plasma. Dissolved in blood plasma. Not water soluble LIPIDS NITROGENOUS WASTE Fatty acids and glycerol (packaged lipids) Transported in diluted forms dissolved in blood plasma Dissolved in blood plasma. OTHER PRODUCTS OF DIGESTION Protein in Amino acids Sugars in Glucose Explain the adaptive advantages of haemoglobin Presence of Nucleus No Yes Red Blood Cells White Blood Cells Function Carries Oxygen to cells Fights pathogens Size 7-8 12-14 Number per ml 5-6 million 10,000 Ability to move from blood vessel to tissue
No Yes Function Carries Oxygen to cells Fights pathogens Water: can be removed from Size 7-8 12-14 Number per ml 5-6 million 10,000 Haemoglobin can carry 4 oxygen molecule - Red Blood Cells contain no nucleus and are concave - Oxygen is relatively insoluble in blood plasma - Bonding of each oxygen molecule slightly alters the shape of the haemoglobin, making it easier for subsequent molecules to bind. Increasing the rate and efficiency of oxygen uptake - Haemoglobin s capacity to release oxygen increases in the presence of carbon dioxide - Once haemoglobin releases oxygen, it has increased ability to pick up CO 2 Compare the Structure of Arteries, Capillaries and veins in relation to their function Presence of Nucleus No Yes Ability to move from blood vessel to tissue No Yes Life Span 120 days 13-20 days BLOOD VESSEL ARTERIES From heart STRUCTURE/ DIAGRAM FUNCTION Thicker walls as it carries blood away from the heart at high pressure - Thick layers of smooth muscle to withstand fluctuations as heart pumps - Walls have elastic fibres - small lumen
VEINS To heart CAPILLARIES - Walls of veins are thinner because blood is at lower pressure - close to muscles, hence, when muscles contract they compress the walls of the veins - Valves preventing backflow of blood - large lumen - Structure is suited to slowing down the flow of blood (better diffusion) - thin walls (1 cell thick) CONNECTIVE TISSUE ELASTICFIBRES/ SMOOTH MUSCLE ENDOTHELIAL LAYER NOTE THE VALVE NOTE THAT THE WALL OF THE CAPILLARY IS VERY THIN COMPARED TO THAT OF THE OTHER BLOOD VESSELS. - small lumen (single file) Describe the main changes in the chemical composition of blood as it moves around the body and identify tissues in which these changes occur Location Lungs Lungs Villi of small intestine Liver Chemical composition that changes concentration High CO 2 concentration entering Lower conc. as it leaves lungs Entering: Low as used by cells Leaving: high Amino acids + glucose: increase conc. as it leaves small intestine Why the change in concentration occurs Waste product of respiration O2 used in respiration highest after lungs Amino acids + glucose are products of digestion Glucose if too much glucose in blood liver removes and stores it as glycogen If too little glucose, liver converts glycogen to glucose Results in low blood sugar levels Results in high blood sugar Lungs Leaving: high after lungs
Powered by TCPDF (www.tcpdf.org) - Used to control blood clotting Villi of small intestine Amino acids + glucose: increase Amino acids + glucose are conc. as it leaves small intestine products of digestion Liver Kidneys Kidneys Glands Glucose if too much glucose in blood liver removes and stores it as glycogen If too little glucose, liver converts glycogen to glucose Results in low blood sugar levels Results in high blood sugar Water: can be removed from blood or reabsorbed into blood during filtration process Nitrogenous waste produced in liver, high Low in conc. after kidney conc. before kidney Endocrine glands secrete hormones into blood Moving hormones Pituitary pancreas Thyroid ovaries/testis Hypothalamus