SNAB T1 Teaching scheme (107 KB)

SNAB T1 Teaching scheme

Topic 1 Lifestyle, health and riskThis teaching scheme is divided into three parts. Introduction. Road map: a suggested route through Topic 1. Guidance notes for teachers and lecturers. These include a commentary that runs

parallel with the student book with hints and tips on teaching and references to the associated activities.

There are more detailed notes about individual activities in the teacher/lecturer sheets accompanying most activities.

Introduction

The Road map starting on page 2 is a suggested route through Topic 1.

The learning outcomes are numbered as in the specification.

There is an AS summary chart at the end of the guidance notes. This shows where concepts are introduced and revisited in later topics.

If two teachers/lecturers are sharing a group for Topic 1, the first could start at Session 1 with the second starting at Session 8 and completing the remaining sessions in a slightly different order – 8, 9, 10, 12, 13, 14, 15, 16, 17, 18, 19, 11, 20/21, 22 and 23. This means that the second teacher would have a larger chunk of the content. The first teacher could either start the next topic once they have done sessions 1 to 7, or pick up Sessions 20–23. By the time the students do blood pressure, Session 11, with the second teacher, they should have covered the structure of blood vessels (session 5) with the first teacher.

It is assumed that each session is approximately an hour in length. There are more activities than can be done in the time available in most centres, so select a balanced collection according to your and your students’ interests, and the time and resources available. Some activities are labelled ‘Core’. Core activities contain experimental techniques included in the specification, and may appear in questions on the unit exam for this topic. These learning outcomes are in bold in the specification, and in the Road map grid below. They are underlined in the Guidance notes below. In the Road map grid, activities are in italics if there is an additional activity covering the same material more directly. Choose which activities students complete, and substitute your own activities as appropriate.

The Core practicals, and any other practicals completed by students, can be used to verify practical biological skills as part of the Unit 3 coursework assessment.

There are various activities – particularly the interactive tutorials associated with some of the activities – which could be completed by students outside of class time. These activities are shown in the lower half of each ‘Possible activities’ box.

Salters-Nuffield Advanced Biology, Edexcel Pearson © University of York Science Education Group 2008downloaded from www.advancedbiology.org This sheet may have been altered from the original. 1


Road map: a route through Topic 1 ‘Lifestyle, health and risk’

Session Areas to be covered Possible activities

1

Introductory presentation (Interactive)Activity 1.1 Mark’s and Peter’s stories (A1.01L)GCSE review and GCSE review test (Interactive)

2

Why a heart and circulation?

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

Activity 1.2 Demonstrating mass flow (A1.02L) (Practical)

Read Key biological principles box and complete questions including Checkpoint question 1.1

3

Structure of the heart and location of blood vessels

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

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

Activity 1.3 Structure of the heart (dissection) (A1.03L) (Practical)

Activity 1.4 Structure of the heart (simulated dissection) (Interactive tutorial alternative to Activity 1.3) (A1.04L)

4

The transport medium

2 Explain the importance of water as a solvent in transport, including its dipole nature.

Activity 1.5 An ideal transport medium

5

The structure and function of blood vessels

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

Activity 1.6 Investigating arteries and veins (A1.06L) (Practical)

Checkpoint question 1.2

6

The cardiac cycle

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

Activity 1.7 The cardiac cycle (A1.07L) (Interactive tutorial)





7

Events that lead to atherosclerosis

11 Explain the course of events that leads to atherosclerosis (endothelial damage, inflammatory response, plaque formation, raised blood pressure).10 Describe the blood clotting process (thromboplastin release, conversion of prothrombin to thrombin and fibrinogen to fibrin) and its role in cardiovascular disease (CVD).

Activity 1.8 Atherosclerosis (A1.08L)

8

Risk

18 Analyse and interpret quantitative data on illness and mortality rates to determine health risks (including distinguishing between correlation and causation and recognising conflicting evidence).20 Explain why people’s perceptions 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).

Activity 1.9 Estimating risk (A1.9L)


9

Identifying risk factors for CVD

19 Evaluate 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).

Activity 1.10 Identifying risk factors (A1.10L)

10

CVD risk factors – age and gender

12 Describe the factors that increase the risk of CVD (genetic, diet, age, gender, high blood pressure, smoking and inactivity).

Brainstorm CVD risk factors

Activity 1.11 Analysis of cardiovascular disease data (A1.11L)

11

CVD risk factors – blood pressure


Activity 1.12 Measuring blood pressure (A1.12L) (Interactive, Practical)

Activity 1.13 Blood pressure summary (A1.13L)




12

CVD risk factors – dietary factors

Carbohydrate structure

3 Distinguish between monosaccharides, disaccharides and polysaccharides (glycogen and starch – amylose and amylopectin) and relate their structures to their roles in providing and storing energy (-glucose and cellulose are not required in this topic).4 Describe how monosaccharides join to form disaccharides (sucrose, lactose and maltose) and polysaccharides (glycogen and amylose) through condensation reactions forming glycosidic bonds, and how these can be split through hydrolysis reactions.

Molymods or other models could be used.

Activity 1.14 Carbohydrate structure (A1.14L) (Interactive)

13

Use of immobilised enzymes

4 Describe how monosaccharides join to form disaccharides (sucrose, lactose and maltose) and polysaccharides (glycogen and amylose) through condensation reactions forming glycosidic bonds, and how these can be split through hydrolysis reactions.

Activity 1.15 Biotechnology to the rescue (A1.15L) (Practical)

14

Lipid structure

5 Describe the synthesis of a triglyceride by the formation of ester bonds during condensation reactions between glycerol and three fatty acids and recognise differences between saturated and unsaturated lipids.

Activity 1.16 Lipids (A1.16L) (Interactive)

15

Energy budgets

17 Analyse data on energy budgets and diet so as to be able to discuss the consequences of energy imbalance, including weight loss, weight gain, and development of obesity. 15 Discuss how people use scientific knowledge about the effects of diet (including obesity indicators), exercise and smoking to reduce their risk of coronary heart disease.

Discussion of BMI and waist-to-hip ratio measurements

Activity 1.17 Your energy budget (A1.17L) (Interactive)

16Cholesterol

14 Analyse and interpret data on the

Using information in the student book, prepare a leaflet explaining in simple terms



Session Areas to be covered Possible activities possible significance for health of blood cholesterol levels and levels of high-density lipoproteins (HDLs) and low-density lipoproteins (LDLs). Describe the evidence for a causal relationship between blood cholesterol levels (total cholesterol and LDL cholesterol) and CVD.

about HDLs and LDLs in relation to heart disease.

Activity 1.18 Cholesterol and CVD – correlation or causal link? (A1.18L)

17

Other risk factors – genetics


Activity 1.19 Sudden death in athletes (A1.19L)

18

Other risk factors


Activity 1.20 Are you getting enough antioxidants? (A1.20L)

Activity 1.22 Reducing stress (A1.22L) (Interactive, Practical)Activity 1.22 Healthy heart quiz (A1.22L)

19

Other risk factors

12 Describe the factors that increase the risk of CVD (genetic, diet, age, gender, high blood pressure, smoking and inactivity).16 Describe how to investigate the vitamin C content of food and drink.

Activity 1.21 Is high C all it claims to be? (A1.21L) Core practical

20/21

Effect of caffeine on the heart rate

9 Describe how the effect of caffeine on heart rate in Daphnia can be investigated practically, and discuss whether there are ethical issues in the use of invertebrates.

Activity 1.23 Does caffeine affect heart rate? (Core) (A1.23L) (Practical)

22

Reducing the risks of CVD

13 Describe the benefits and risks of treatments for CVD (antihypertensives, plant statins, anticoagulants and platelet inhibitory drugs).

23Reducing the risks of CVD

15 Discuss how people use scientific knowledge about the effects of diet

Activity 1.25 Making decisions (A1.25L)



Session Areas to be covered Possible activities (including obesity indicators), exercise and smoking to reduce their risk of coronary heart disease.

Extension 1.3 Functional foods and CHD (A1.3L)

Extension 1.4 New treatments for coronary heart disease (X1.04S)

Guidance notes for teachers and lecturers

It may be helpful to have completed these continuing professional development modules from the software before starting Topic 1: CPD1 A road map for SNAB: Building knowledge and principles through the course and CPD2 Contextualised biology teaching through storylines.

Introduction and GCSE review The context for this topic is cardiovascular disease and the lifestyle factors which increase the risk of developing the disease. Student book Topic 1 starts with an introduction including, an overview of the biological principles to be covered. The GCSE review and the GCSE review test cover the main GCSE ideas that students will be expected to draw on during the topic – the heart, circulation and nutrition. The test itself is open access and it is assumed that the test will be completed outside of class time. Students are likely to work co-operatively and marks will not necessarily reflect the understanding that an individual student brings to the topic. However, the accompanying review will refresh the student’s memory so that less time need be spent going back over KS4 material in class.

The second spread presents the stories of two individuals with experience of cardiovascular disease. This introduces the context to students. The stories are referred back to during the topic.

Mark and Peter, both apparently healthy individuals, suddenly experienced the effects of cardiovascular disease. Mark suffered a stroke in 1995 when he was 15. Peter had a heart attack in 2002 aged 63. The topic goes on to look in detail at the biology underlying cardiovascular diseases. It then considers the concept of risk and the lifestyle factors that increase the risk of cardiovascular disease and may have contributed to the problems experienced by Mark and Peter.

An interactive presentation introduces the whole topic. This could be left until the students have been introduced to Mark and Peter.

Activity 1.1 Mark’s and Peter’s stories (A1.01L)This activity presents the full-length version of Mark’s and Peter’s stories; the student book has shortened accounts. Mark and Peter wrote their own stories, providing personal accounts of their experiences of having a stroke and heart attack – these are genuine stories written by real people. Students could complete this activity for homework. The rest of the topic presents the biology needed to understand what happened to Mark and Peter, or could happen to anyone with CVD.

1.1 What is cardiovascular disease?See the CPD module CPD3 Developing practical skills for advice on doing practical work with students.



The student book briefly introduces cardiovascular disease and the scale of the problem before going on to consider why animals have a heart and circulation.

Activity 1.2 Demonstrating mass flow (A1.02L)This activity makes a comparison between the speed of diffusion and speed of mass flow. The student sheet gives a detailed procedure but you could do a demonstration as a starting point for discussion about why animals (and plants for that matter) have circulatory systems. The Key biological principle box ‘Why have a heart and circulation’ covers the ideas. As homework, students could read the box and answer the questions in the student book including the Checkpoint question 1.1. In-text questions Q1.1 to Q1.4 have answers at the end of the student book, but the answer to the Checkpoint question is only given in the teachers’/lecturers’ online resources.

Activity 1.3 and 1.4 Structure of the heart (A1.03L and A1.04L) The structure of the heart is revised by dissection (Activity 1.4) or using a computer simulation (Activity 1.5). The two activity sheets cover exactly the same ideas. The major arteries and veins of the heart, including the coronary arteries, are located. These activities could provide an introduction to the heart and circulation here, or be left until after Activity 1.5 when considering in more detail how the circulation works.

How does the circulation work?The section starts with a brief consideration of the transport medium; details of blood cells, transport of gases etc are not required. The important point is that blood is a transport medium. You can link this with the properties of water. The Key Biological Principles box introduces polarity and solvent properties of water. The properties of water are revisited and extended in Topic 4. Activity 1.5 Properties of water (A1.05L)The interactive tutorial introduces some of the properties of water.

The student book considers the detailed structure of the heart and blood vessels. The dissection of the heart could be left until this point, to highlight the location and function of the arteries and veins.

Activity 1.6 Investigating arteries and veins (A1.06L)The relative recoil of arteries and veins are compared in this practical, and related to the structure of their walls as viewed under the microscope. The questions on the activity sheet relate the structures of the blood vessels to their functions. The activity sheet is written to highlight certain practical skills as detailed on the teacher sheet that accompanies the activity. There is extra support in the Student skills support sections: Exam/coursework support and Practical support. Q1.5 and Checkpoint question 1.2 in the student book also requires students to relate blood vessel structure and function.

Activity 1.7 The cardiac cycle (A1.07L)Students need to be able to relate the structure and operation of the mammalian heart to its function. Understanding this will enable students to appreciate the consequences of any blockage of the coronary vessels. The cardiac cycle is described in detail in the student book. In this activity students use the animation to get a better impression of the cardiac cycle’s continuous nature before completing the activity sheet.

Checkpoint question 1.3 asks students to summarise the events in the cardiac cycle.

Students could use the animation to complete the Checkpoint question, and be asked to learn details of the cycle for a test at the start of the following session. The worksheet could then be used for the assessment exercise.



The student book introduces heart attacks and ischaemic strokes, and describes in detail what happens in the process of atherosclerosis. (We do not use the term ‘hardening of the arteries’ for this process, because with advancing years artery walls do become less elastic and ‘harden’ whether or not there is any atherosclerosis.)

Activity 1.8 Atherosclerosis (A1.08L)It is best if students read the sections on both atherosclerosis and blood clotting in the student book before completing this activity. They could read these sections in advance of a lesson, or in the first half of a lesson, without making notes. Groups of students could each be given the key word cards to sort into the correct description. The first sheet of the activity would not need to be copied and distributed if oral instruction were given. Each student could be asked to produce their own description, flow chart or series of annotated diagrams. Alternatively, diagrams of sections of a normal and a diseased artery could be annotated to explain the processes.

There are more micrograph diagrams available on the websites in the weblinks accompanying this activity.

Students should realise why only arteries are prone to atherosclerosis. After the previous three activities they should be able to suggest the reasons – these are also explained in the student book. There is more detail on the measurement and control of blood pressure later in the topic.

The consequences of atherosclerosis are described in the student book. Detailed knowledge of the symptoms of CVD are included in a ‘Did you know box but not required by the specification. ’. The British Heart Foundation and Stroke Association have good websites with detailed accounts (see general web-links for Topic 1).

Extension 1.1 Someone saved my life today (X1.01S)Cardiopulmonary resuscitation (CPR) is not in the specification learning outcomes, but it reinforces the need for the heart and circulation. Compression of the chest maintains circulation while ventilation ensures a continued supply of oxygen to the blood. This activity would raise students’ awareness of life-saving skills. The British Heart Foundation ‘Heart Start’ programme teaches emergency life support (ELS) skills in school.

Extension 1.2 Techniques used in medical diagnosis of CVD (X1.02S)This extension included details of the techniques used in the diagnosis of CVD. The use of ECG, CAT and MRI are all included in the A2 course.

1.2 Who is at risk of cardiovascular disease?What do we mean by risk?The concept of risk is introduced, .and the numerical value produced by calculating probabilities is explained. The student book gives a stepwise explanation of how to calculate probabilities.

Activity 1.9 Estimating risk (A1.09L)This activity gives students the opportunity to estimate risks and think about the perception of risk, including the overestimation and underestimation of risk. Correlation and causation are also included. The Chemical Industry Education Centre (CIEC) ‘Risk-ed’ website gives lots of information about risk and provides some good chemical examples. The post-16 ‘Teaching About Science’ section of the Nuffield Curriculum Centre website contains downloadable resources for an activity on risk and mobile phones. The evidence of health risks from mobile phone use is presented to students who are asked to assess the strength of the evidence on the basis of its validity, reliability and repeatability. See the general web-links for Topic 1.



The BioEthics Education Project (BEEP) website section on How Science Works includes a section on understanding the maths, including Fractions, Percentages and Expressing Risks. See the web-links for this activity.

Students need to understand that a strong association between two variables does not necessarily prove a causal link between them. This idea of causal links could also be illustrated with some mistaken correlations. For example, up until the end of the nineteenth century it was widely thought that bad air caused malaria. It was not until 1880 that the French army doctor Alphonse Laveran proposed that it was caused by a parasite. In 1897 the British doctor Sir Ronald Ross observed the parasite in mosquitoes that had fed on infected individuals. Ross’s description of the complete life cycle of the malarial parasite won him the Nobel Prize for Medicine in 1902. Illicit drug use was one of the early suggestions for the cause of AIDS until HIV was identified. Q1.10 in the student book presents a few correlations and asks the reader to decide if there could be a causal link in each case.

Checkpoint question 4 requires students to consider the circumstances that make people more likely to underestimate or overestimate risk.

The student book considers what is meant by risk factors, and how correlation and causation are important in identifying risk factors associated with human health. This then leads into a detailed discussion of the major risk factors for cardiovascular disease.

1.3 Risk factors for cardiovascular disease Identifying risk factors for CVDA lot of the risk factors for CVD will be familiar to students, so a good starting point is a brainstorm of their ideas. In excess of 250 risk factors have been suggested. In some cases there is a correlation between CVD incidence and the risk factor, but without a causal link having been shown. Examples of such correlations include not having siestas, snoring, having English as a mother tongue, and not eating mackerel. Before looking in detail at the widely accepted risk factors the student book considers how these risk factors were identified in epidemiological studies. The student book describes cohort and case-control studies and considers the features of a good study. Checkpoint question 1.5 requires students to produce a checklist of these features. This could be done before the students complete the activity.

Activity 1.10 Identifying health risk factors (A1.10L)This activity allows students to evaluate the design of some epidemiological studies used to determine health risk factors. Studies investigating the link between MMR and autism are considered; the sense about science website page on this issue provides some useful weblinks to access additional information.

The student book goes on to present the risk factors which are widely accepted as causally contributing to an increased risk of developing CVD. There are student activities linked to most of these risk factors.

Smoking is very probably the largest self-imposed risk factor. Students are likely to have covered this issue in KS3 and/or KS4 so this should be largely recall. There is no activity on smoking but there is summary information included in the student book. If students have not come through the standard English and Welsh GCSE route it may be worth highlighting this information.



Age and gender make a differenceActivity 1.11 Analysis of cardiovascular disease data (A1.11L)This activity requires students to analyse and interpret quantitative data on illness and mortality rates focusing on the effect of age and gender. It is in two parts: analysis of the risk of haemorrhagic stroke, and analysis of coronary heart disease data. In the introductory story Mark suffered a haemorrhagic stroke; this is where a blood vessel in the brain bursts. This type of stroke is described at the end of the topic when the text returns to Mark and Peter to consider their possible risk factors. The student book also gives mortality data for different ages and both sexes, with questions.

In the 2005 version of the SNAB book, heredity (My Dad had a heart attack – will I?) comes immediately after age and gender, in the 2008 version this has been moved to later in the topic so that more up-to-date information on the gene cluster that has been associated with CVD can be included. This requires knowledge of LDLs and HDLs, so it appears after the section on fats.

High blood pressure Activity 1.12 Measuring blood pressure (A1.12L)Students measure blood pressure. If a sphygmomanometer or blood pressure monitor is not available, the simulation on the website can be used. The simulation could also be used alongside the practical to confirm understanding of the technique.

The student book explains what determines blood pressure. It includes information on tissue fluid formation and oedema. This detail is not required in the specification, but is given here to illustrate the consequences of high blood pressure. The student book also links back to the development of atherosclerosis.

Activity 1.13 Blood pressure summary (A1.13L) Ideas about blood pressure are summarised using a concept map. This also reminds students about a useful revision technique. Dietary risk factorsThere is a detailed consideration of carbohydrates and fats, including their role in the diet, and potential as a risk factor for cardiovascular disease. In preparation for this section, students could be asked to look at food packaging at home and to list the different energy units used. It is likely that within any group there will be calories, kilocalories, Calories and kilojoules. The student book explains the relationship between these units.

Activity 1.14 Carbohydrate structure (A1.14L)This interactive tutorial takes the student through the structure of monosaccharides, disaccharides and polysaccharides. It shows condensation and hydrolysis reactions. Students need to be able to distinguish between monosaccharides, disaccharides and polysaccharides (glycogen and starch – amylose and amylopectin) and relate their structures to their roles in providing and storing energy. They need to be able to describe condensation and hydrolysis reactions involved in their formation. The structure and function of cellulose is covered in Topic 4, but the knowledge that it is a polysaccharide and has a role as dietary fibre is assumed here.

Molymods or similar models could be used to demonstrate the formation of disaccharides and polysaccharides. It is possible to demonstrate the synthesis of starch using an enzyme extracted from potatoes. This highlights the involvement of an enzyme which is not featured in the interactive tutorial on carbohydrates. Practical details are given in Practical Advanced Biology by Tim King and Michael Reiss (Nelson Thorne, 2001).



Activity 1.15 Biotechnology to the rescue (A1.15L) This activity confirms the idea that disaccharides can be hydrolysed to produce monosaccharides. Set in the context of the use of immobilised enzymes in the food industry, this activity uses lactase to hydrolyse lactose in milk. The lactase is first immobilised in alginate gel beads. Students have to recall their GCSE knowledge of enzymes. A question asks students to explain what has happened in the experiment. They can use GCSE enzyme knowledge and the information on hydrolysis reactions in their answer. The mechanism of enzyme action is covered in detail in Topic 2.

The activity could introduce some ideas about practical skills. At the end of the activity sheet students are asked to plan an experiment to investigate the effect of rate of flow on breakdown of lactase. A class discussion could consider formulating a hypothesis, designing an experiment that will test the hypothesis, how valid results are produced and the idea of error.

Activity 1.16 Lipids (A1.16L)This interactive tutorial goes through the structure of lipids. The accompanying worksheet can be completed using the interactive tutorial or the diagrams in the student book.

Activity 1.17 Your energy budget (A1.17L)This interactive tutorial allows students to calculate their BMR and energy expenditure for a day. Students are asked to select a typical day’s diet from a simple menu, and the energy content is compared with their requirements. There are more comprehensive diet analysis packages available, but this one is less time-consuming and still highlights the need for an energy balanced diet. Note that the energy values are given in kilocalories (Calories) rather than kilojoules. Students should appreciate that although Calories are quite often used when dealing with food, they are not SI units. There is a Practical support sheet on SI units (P0.05S). The activity sheet goes through the same procedure as the interactive tutorial and could be used without computer access.

The activity provides a starting-point for discussion of energy imbalance and obesity. A great deal of sensitivity may be required if students are asked to calculate their own body mass indices or waist-to-hip ratio using the methods described in the student book. Another possibility is to have a few imaginary persons, and use their heights and masses to calculate BMIs and waist-to-hip ratios. If any students calculate their own indices and are anxious about the results they obtain, it would be best to recommend that they consult their doctor to obtain a professional assessment of body size and health implications. Any discussion about addressing the problem of obesity should emphasise the need for a healthy balanced diet and sufficient exercise. It should also refer to the dangers of very low energy and restricted food group diets.

The students could be asked to write a short report for an imaginary person with a BMI of 35 explaining to them what this means and the potential problems resulting from being substantially overweight. Alternatively, they could be asked to suggest information to be printed out from weighing scales in superstores across the country. (A person stands on the scale, answers a simple question about their height, and receives a slip of paper telling them their BMI and giving a paragraph of information about it.)

Students need to understand the role of high-density lipoproteins and low-density lipoproteins in relation to cardiovascular disease. Their roles as transport proteins, and how they contribute to development of atherosclerosis, is covered in the student book. Students could prepare a leaflet or poster for use in a local pharmacy. It should be emphasised that we need cholesterol and fats in our diet. The evidence for a correlation and a causal link between blood cholesterol levels and CVD is considered in the activity. The student book highlights the conflicting evidence for a correlation between cholesterol levels and CVD. The



French and UK total cholesterol levels are about the same, but the incidence of CVD in France is lower. The possible explanations of this paradox are discussed.

There is a very good article and worksheet in the journal Biological Sciences Review: O’Connell N., Ottewill G. and Mills G. (2000) Heart disease and cholesterol. Biological Sciences Review, 13(2), 2–7.

Activity 1.18 Cholesterol and CVD – correlation or causal link? (A1.18L)In this activity data from epidemiological studies is used to investigate the correlation between cholesterol and CVD. The difference between a correlation and causal link is highlighted with the type of evidence for the latter presented.

After looking at the key dietary factor of energy balance and cholesterol, other risk factors are presented in the student book in an order that reflects their importance in increasing risk of CVD. The key lifestyle factors, smoking and inactivity are covered before considering heredity. The section finishes with a summary of a range of other factors - antioxidants, salt, stress and alcohol. The diet-related factors could be dealt with alongside carbohydrates and fats before the other lifestyle factors.

Activity 1.19 Sudden death in athletes (A1.19L)This activity relates how the predisposition for cardiovascular disease can be inherited. Inheritance is covered in more detail in Topic 2.

Activity 1.20 Are you getting enough antioxidants? (A1.20L)The worksheet provides information about how antioxidants are thought to help prevent damage to cells by radicals. It then allows students to assess their own diet for antioxidants.

Activity 1.21 Is high C all it claims to be? (A1.21L) Core practical In this activity students investigate the vitamin C content of fruit juice or other foodstuffs. The activity sheet presents the true story of New Zealand high school students who found that the levels of vitamin C in Ribena were much lower than those the manufacturer claimed it contained.

Activity 1.22 Reducing stress (A1.22L) This teacher-led activity shows that stress can affect heart rate and blood pressure, and that stress relief techniques can have a measurable effect on both pulse rate and blood pressure. Stress does not appear in the specification, but the activity can be used to highlight the link between stress and high blood pressure.

Activity 1.23 Does caffeine affect heart rate? (A1.23L) Core practical The first part of this activity is a planning exercise. The student is asked to produce a detailed experimental plan to compare the effects of caffeine on the heart rate of Daphnia (water fleas). An equipment list is provided and a checklist of things students’ plans should include.

Students could perform their own experiment or use the procedure on the teacher sheet. This is a difficult experiment to perform with precision. The experiment provides much to discuss in terms of validity of data, and the precautions needed to ensure that the experiment is conducted with consideration for living organisms. The specification requires students to discuss whether there are ethical issues in the use of invertebrates. The BioEthics Education Project (BEEP) website includes a section on use of animals in research, noting that many invertebrates are used in research, but are not protected under British law. There is also a section on How Science Works with information about reliability and validity. See the web-links accompanying this activity.



Activity 1.24 Healthy heart quiz (A1.24L) This true–false quiz draws on ideas covered in the preceding section. Discussion of the answers provides an opportunity to review all the risk factors.Checkpoint question 1.6 summarises the risk factors for CVD and their effects.

1.4 Reducing the risks of cardiovascular diseaseThis section can involve students in a discussion about ways to reduce the risk of CVD. Before reading it, every student could be asked to write down one way that the risk of cardiovascular disease could be reduced. The group could then share ideas and discuss which are the most realistic for an individual to adopt. The student book summarises some ideas. It includes details of drugs used in the control of blood pressure, and to lower blood cholesterol levels; it does not make any recommendations. The use of anticoagulant and platelet inhibitory treatment to prevent clot formation is also considered. The need to assess the risk and benefits when using any of these drug treatments is highlighted in the text.

Lack of physical activity is acknowledged as a major contributor to the development of CVD. Although in the topic this is not given an independent section, it is vital to include physical activity in any discussion of ways to reduce the risk of not only CVD but also a range of other diseases such as obesity and cancers.

Activity 1.25 Making decisions (A1.25L)Students look at how people might use scientific information to reduce their risk of coronary heart disease by answering questions with a range of stimulus material.

Extension 1.3 Functional foods and CHD (A1.3L) This extension looks in detail at the development of functional foods, using the Flora pro.Activ story as an example. This extension gives details of trials showing the effectiveness of plant sterols and stanols in reducing CHD risk.

Extension 1.4 New treatments for coronary heart disease (X1.04S)This extension considers treatments for people who have had a heart attack or stroke, including surgery and emergency drug treatment.

The topic finishes by referring back to Mark and Peter. A review of their risk factors could be used to finish the topic. Peter’s situation highlights the need for a healthy diet and exercise throughout life; his doctors doubted that he would have survived if he had not been as fit. Mark’s story is almost a red herring in that he may well have had a weak vessel and an inherited predisposition, the more common risk factors discussed in the student book seem to play a minor role in his condition. However, having had one such stroke there is undoubtedly a need to avoid things that could potentially put additional strain on the vessels in his brain.

Activity 1.26 Check your notesStudents can use the checklist of learning outcomes in this activity in their revision.

End-of-topic testsThere is an online interactive end-of-topic test. This test is not accessible to students initially unless set by their teacher/lecturer. The teacher has the option to ‘flick a switch’ to make it open access. There is also a paper-based test for Topic 1 with examination-style questions on the teachers’ and technicians’ sites. A mark scheme is also available on these sites. The questions are similar in layout and style to those found on exam papers. However, the restriction of questions to only one topic in each test has meant that it has not been possible to include some types of questions that draw on material from different topics.



AS Summary chart

The grid below shows where concepts are introduced and then revisited in later topics.Note: Some of these concepts will be revisited and built on in A2.

Concept Topic 1 Topic 2 Topic 3 Topic 4Biological molecules (monomers combine to form polymers)

Carbohydrate structures and roles in providing and storing energy (not cellulose)

Lipid structures

Phospholipids Protein structures Structures of DNA and RNA

Starch and cellulose structures and functions

Enzymes Enzyme structure and mechanism of action

Effect of enzyme concentration on rate of reaction

Role of ER and Golgi apparatus in formation of extracellular enzymes

Chemical reactions

Condensation and hydrolysis reactions

Antioxidants and radicals

Condensation reactions Hydrophobic and

hydrophilic effects

Condensation reactions

Cell structure Unit membrane structure Prokaryotic and typical eukaryotic (animal) cell structure and ultrastructure

Role of ER and Golgi apparatus in protein transport

Gamete structures and functions Stem cells Cell specialisation and

organisation into tissues, organs and organ systems

Recall typical ultrastructure of animal cell and compare with plant cell ultrastructure

Xylem and sclerenchyma structure and function

Genes help determine the nature of organisms

Roles of DNA and RNA Genetic code Protein synthesis DNA replication and

mutations

Cell specialisation through differential gene expression

Genetic diversity

Cell cycle DNA replication and cell and nuclear division

Role of mitosis and cell cycle for growth and asexual reproduction

Differentiation and the role of stem cells

Energy Energy units, energy balance Role of ATP in active transport

Transport in and out of cells

Passive transport, diffusion, facilitated diffusion, osmosis, active transport, exocytosis and endocytosis

Protein transport Diffusion and osmosis

Salters-Nuffield Advanced Biology, Edexcel Pearson © University of York Science Education Group 2008This sheet may have been altered from the original. 14


Concept Topic 1 Topic 2 Topic 3 Topic 4Transport in organisms to and from exchange surfaces

Mass transport Structure and function of the

circulatory system Solvent properties of water

Mass transport of waters and minerals through plant stems

Organisms exchange materials with the environment

Surface area to volume ratio

Properties of gas exchange surfaces

Inheritance Genetic risk factors for CVD Interaction of genotype and the

environment on development of CVD

Monohybrid inheritance Importance of meiosis and fertilisation in sexual reproduction

Role of meiosis in production of genetic variation, including independent assortment and crossing over

Some characteristics are affected by genotype and the environment

Polygenic inheritance Discontinuous and continuous

variation

Genetic variation (loss and conservation)

Gene technology Gene therapy Gene therapy Genetic screening and

embryo testing Evolution and natural selection

Importance of meiosis and fertilisation in sexual reproduction

Introduction of genetic variation through random assortment (stages of meiosis and chiasmata formation are not required)

Some characteristics affected by genotype and the environment

Adaptation Evolution by natural selection

Classification Prokaryotes and eukaryotes The concept of species Taxonomic groupings

Interactions with the environment

Effect of environment on CVD risk

Some characteristics are affected by genotype and the environment

Biodiversity Endemism Concept of Niche Adaptations of organisms Sustainable resource utilisation Microbial properties of plants

importance of water and mineral ions to plants

Energy flow and recycling of materials in ecosystems

Sustainable resource utilisation



Concept Topic 1 Topic 2 Topic 3 Topic 4Coordination Diabetes Endocrine and exocrine

hormones introduced Melanocyte stimulating

hormone (MSH)

Risk and perception

Concept of risk, risk perception, risk factors for CVD, reducing risk of CVD

Genetic risk factors Risk factors for cancer

Maths/science skills

Calculating probabilities, correlation and causation, calculating obesity indicators, analysis of quantitative health data

Calculating surface area to volume ratios

Continuous/discontinuous variation

The nature of theories, scientific consensus and evidence

Critical evaluation of new data Ecological sampling Measurement of biodiversity and

genetic diversityHealth and Disease

CVD (CHD and stroke) Cancer Atherosclerosis Blood clotting Evaluate design of health studies

Cystic fibrosis, (briefly) sickle cell and thalassaemia, PKU, achondroplasia, Huntington’s disease)

Cancer Drug development

Ethics Experimental use of invertebrates

Ethical frameworks Genetic screening

Stem cells

Applications of biology

Sphygmomanometers / blood pressure monitors

Use of scientific knowledge to reduce health risk

Genetic testing / screening Gene therapy

Use of stem cells for research Use of plant fibres Use of plant starch and oils Drug development Role of zoos and seedbanks


SNAB T1 Teaching scheme (107 KB)

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Transcript of SNAB T1 Teaching scheme (107 KB)