IAL Biology Unit 1

Topic 1 – Molecules, Transport and Health

1.1 Importance of water as a solvent in transport

Including its dipole nature

1.2 Carbohydrates

(i) Know the difference between monosaccharides , disaccharides , and polysaccharides , including glycogen and starch (amylose and amylopectin)

(ii) Relate the structures of monosaccharides , disaccharides , and polysaccharides to their roles in providing and storing energy

Note: β-glucose and cellulose are not required in this topic.

1.3 CORE PRACTICAL 1

Use a semi-quantitative method with Benedict’s reagent to estimate the concentrations of reducing sugars and with iodine solution to estimate the concentrations of starch , using colour standards.

1.4 Formation and Breakdown of Carbohydrates

Know how monosaccharides (glucose, fructose, and galactose) join together to form disaccharides (maltose, sucrose, and lactose) and polysaccharides (glycogen, amylose, and amylopectin) through condensation reactions forming glycosidic bonds , and how these can be split through hydrolysis reactions.

1.5 Lipids

(i) Know how a triglyceride is synthesised by the formation of ester bonds during condensation reactions between glycerol and three fatty acids

(ii) Know the differences between saturated and unsaturated lipids

1.6 Heart and Circulation

Understand why many animals have a heart and circulation (mass transport to overcome the limitations of diffusion in meeting the requirements of organisms)

1.7 Structure of Blood Vessels

Understand how the structures of blood vessels (capillaries, arteries, and veins) relate to their functions

1.8 Cardiac Cycle

Know the cardiac cycle (atrial systole, ventricular systole, and cardiac diastole) and relate the structure and operation of the mammalian heart , including the major blood vessels, to its function

Note: Details of myogenic stimulation are not needed at IAS.

RECOMMENDED ADDITIONAL PRACTICAL

Investigate the structure of a mammalian heart by dissection.

1.10 Atherosclerosis

Understand the course of events that leads to atherosclerosis (endothelial dysfunction, inflammatory response, plaque formation, raised blood pressure)

1.12 Risk Factors for Cardiovascular Disease (CVD)

Know how factors such as genetics, diet, high blood pressure, smoking, and inactivity increase the risk of cardiovascular disease (CVD)

1.13 Dietary Antioxidants and CVD

Understand the link between dietary antioxidants and the risk of cardiovascular disease (CVD)

1.14 CORE PRACTICAL 2

Investigate the vitamin C content of food and drink.

1.9 Role of Haemoglobin

(i) Understand the role of haemoglobin in the transport of oxygen and carbon dioxide

(ii) Understand the oxygen dissociation curve of haemoglobin , the Bohr effect and the significance of the oxygen affinity of fetal haemoglobin compared with adult haemoglobin

1.11 Blood Clotting Process

Understand the blood clotting process (thromboplastin release, conversion of prothrombin to thrombin, and fibrinogen to fibrin) and its role in cardiovascular disease (CVD)

1.15 Data Analysis on Health Risks

Be able to analyse and interpret quantitative data on illness and mortality rates to determine health risks, including distinguishing between correlation and causation and recognising conflicting evidence

1.16 Evaluating Study Design

Be able to evaluate the design of studies used to determine health risk factors, including sample selection and sample size used to collect data that is both valid and reliable

1.17 Perception of Risks

Understand why people’s perception of risks are often different from the actual risks, including underestimating and overestimating the risks due to diet and other lifestyle factors in the development of heart disease

1.18 Blood Cholesterol Levels

(i) Be able to analyse data on the possible significance for health of blood cholesterol levels and levels of high-density lipoproteins (HDLs) and low-density lipoproteins (LDLs)

(ii) Know the evidence for a causal relationship between blood cholesterol levels (total cholesterol and LDL cholesterol) and cardiovascular disease (CVD)

1.19 Using Scientific Knowledge to Reduce Risk

Understand how people use scientific knowledge about the effect of diet, including obesity indicators (body mass index and waist-to-hip ratio), exercise, and smoking to reduce their risk of coronary heart disease

1.20 Treatments for Cardiovascular Disease (CVD)

Know the benefits and risks of treatments for cardiovascular disease (CVD) (antihypertensives, statins, anticoagulants, and platelet inhibitors)