Starter and Plenary Suggestions for Exploring Science Unit 7D Page 5

Starter and plenary suggestions for Exploring Science Unit 7D Page 1

Unit 7D – Variation and classification

7Da Being different

Starter Ask pupils to make a list of all the ways in which they are different physically to their classmates, or to friends or family outside school. Give pupils five minutes to compile their own lists, then compile a class list on a large sheet of paper. The lists could include things such as hair colour, length or curliness, eye colour, height, skin colour, shape of ears/nose etc. This is a good opportunity to encourage pupils to see differences as a good thing, rather than something to be criticized. Keep the class list for future lessons, as it can be revisited and pupils asked to classify each type of variation as continuous or discontinuous (if the class has studied the ‘Focus on:’ page for this Topic), or as environmental or inherited (following Topic 7Db).

Plenary Worksheet 7Da/8 (on the web) provides a set of graphs (bar charts, line graphs and scatter graphs) for pupils to interpret. The graphs could be discussed in groups before reporting back to the class. As deciding that there is no relationship between two variables is also a valid interpretation of a graph, some of the graphs provided show no relationship. The graph of height of child against height of parent deliberately shows a poor relationship, as this is a variation that depends strongly on environmental factors as well as inheritance. This graph could be discussed again during Topic 7Db, when environmental and inherited variation are discussed. Skills Sheet 37 provides further practice in interpreting line graphs in terms of the relationship between two variables. If it has not already been used, this Skills Sheet can be used to give pupils further practice in determining the type of relationship between two variables. Answers: 1 No relationship. 2 Taller parents tend to have taller children, but there is not a strong relationship. 3 The plant grows taller if it has more water, up to a certain amount of water. If it gets too much water, its growth is reduced (plants can become waterlogged if over watered). 4 The warmer the nest, the greater the percentage of males in a crocodile clutch. 5 No relationship. 6 The more food someone eats, the greater their mass.

7Db It’s your inheritance/A question of environment

Starter

Exploring Science 7 © Pearson Education 2002 This material may be adapted for use in schools. Starter and plenary suggestions for Exploring Science Unit 7D Page 2

Carry out a CAP exercise using the statements below. Pupils may not get all the possibilities suggested as possible answers, but the exercise should start them thinking about the different causes of variation. It may be worth revisiting the CAP exercise as a plenary session, to see if pupils can add any more possibilities to their answers. Some pupils may be sensitive about discussing their own physical characteristics, so the statements suggested should be general, rather than related to any particular pupil. CAP statements: A boy has brown skin (he has a sun tan, one or both parents had brown skin) A girl has curly hair (she has had her hair permed, one or both parents have curly hair) A girl has blonde hair (she has dyed her hair, one or both parents had blonde hair) Two apples look different to each other (one has had more light/water/fertiliser etc, they are from two different species). One boy is taller than his friend (his parents may be taller than his friend’s parents, he may have had better nutrition when he was growing up).

Plenary The list of differences produced as a starter activity in Topic 7Da could be revisited, and pupils asked to classify each type of variation as inherited, environmental, or both. Alternatively, worksheet 7Db/5 (in Copymaster File 7) can be used to summarise the work covered in this topic. Pupils can answer the questions in writing, or the worksheet could be used as the basis of an oral plenary session. It might be useful to copy the worksheet onto an OHP slide if you want to discuss it with the class.

7Dc Describing differences

Starter This topic deals with different ways of describing organisms. As a starter activity, pupils could be asked to spend 5 minutes describing an animal or a plant, without mentioning the name of their organism. Pupils should be allowed to draw their organism if they wish – stylised representations of animals such as a typical drawing of a cat’s face can often convey the key features of an animal as effectively as a paragraph of prose. Walk around the class while pupils are working on their descriptions, and pick a few descriptions in different styles to be read out (by you or by the pupils themselves). Discuss which pieces of writing give the best clues to the identity of the organism. These may not be the most ‘scientific’ descriptions. This discussion can then lead on to the descriptions provided in the Pupils’ Book, and the purpose of each type of writing.

Plenary Worksheet 7Dc/7 (in Copymaster File 7) provides a set of alien creatures for pupils to classify. Although the Scheme of Work does not specifically require pupils to be able to make keys, the activity does encourage them to consider which features they would choose to use to divide the creatures into groups. The worksheet can be completed individually or in groups, or the pictures could be used as the basis for an oral discussion on how the creatures should be subdivided.

7Dd Classified information

Starter The practical activity suggested as Practical 2 (Sorting animals) is a good starter activity for this topic – see Teacher’s Guide 7 for further details. This activity can be done individually, or with pupils working in small groups. If carried out at the beginning of the lesson, the activity will help you to find out which pupils have already encountered the scientific classification of vertebrates into five groups, and how well they understand this classification. If you wish, you can make the task harder for more able pupils by including some invertebrates in the set of cards. Suitable pictures are provided as worksheet 7Dd/7 (on the web). You may wish pupils to keep a note of their invertebrate classifications to use at the beginning of the next Topic. It is worth stressing to pupils who have come up with groupings different to the five scientifically accepted vertebrate groups that their groupings are not necessarily wrong, and that there are many different ways of grouping organisms. We normally use the vertebrate groups identified in the Pupils’ Book as scientists need a common way of grouping things if the classification is to be useful.

Plenary Worksheet 7Dd/1 (in Copymaster File 7) provides a crossword, and 7Dd/3 (also in Copymaster File 7) provides a wordsearch on vertebrate groups that can be used to summarise the work covered in this Topic. Alternatively, the CAP and Odd One Out suggestions for Topic 7Dd (on the Thinking Skills page in Teacher’s Guide 7) can be used to reinforce the work covered.

7De No backbone!/The arthropods

Starter The practical activity suggested as Practical 3 is a good starter for this topic. Pupils are provided with a set of pictures of invertebrates and asked to sort them into groups. It does not matter whether or not pupils choose the scientifically accepted groups, but they should be able to justify why they have assigned animals to different groups, and identify the features that all the animals in each of their groups have in common. The

Exploring Science 7 © Pearson Education 2002 This material may be adapted for use in schools. Starter and plenary suggestions for Exploring Science Unit 7D Page 4 pictures provided on worksheet 7Dd/7 (on the web) and on Skills Sheet 51 (in Copymaster File 7) can be used. This activity can be extended by then asking pupils to sort the cards in a different way, and again to explain the criteria they have used. The activity then helps to develop thinking skills as well as familiarising pupils with some of the characteristics of invertebrates. As with the starter activity for Topic 7Dd, it is worth stressing to pupils that their groupings are not wrong if they do not agree with the classification they will study in the Pupils’ Book, but scientists need one agreed system, and have chosen to use the system explained in the Book.

Plenary Worksheet 7De/6 provides a set of cards for a question loop activity that can be used to summarise the whole Unit, and act as a starting point for revision. There are 30 cards provided. All cards must be used to close the ‘loop’ – if you do not have 30 pupils in the class, give some pupils more than one card. Alternatively, copy two sets of cards, so each pupil has at least two cards – two hands should then go up in answer to every question, and pupils are less likely to mentally switch off when they have used their card. Answers: What is a species? A group of organisms that can breed together. What does variation mean? The differences between things. Is eye colour an example of inherited or Inherited variation. environmental variation? Is length of hair an example of inherited Environmental variation. or environmental variation? Name an environmental factor that could Acidity of the soil. affect a plant. What does classification mean? Sorting things into groups. What does thorax mean? The middle part of an animal’s body. What does abdomen mean? The rear or bottom end of the main part of an animal’s body. What kind of covering does an amphibian Moist skin. have? What kind of covering does a reptile Dry scales. have? What kind of covering does a bird have? Feathers. What kind of covering does a mammal Hair or fur. have? What kind of covering does a fish have? Wet scales. Which vertebrate groups lay eggs in Amphibians and fish. water? Which vertebrate group gives birth to live Mammals. young? Which group of vertebrates lays jelly- Amphibians. coated eggs?

Which group of vertebrates lays eggs Birds. with hard shells? Which group of vertebrates lays eggs Reptiles. with leathery shells? What feature do all vertebrates have in A backbone. common? How many different groups of vertebrates Five. are there? Which group of invertebrates crawls on a Molluscs. single fleshy pad? Give an example of an arachnid. A spider. What invertebrate group do starfish Echinoderms. belong to? What group of arthropods does a crab Crustacean. belong to? How many pairs of legs do arachnids Four. have? How many sections is an insect’s body Three. divided into? How many legs do insects have? Six. What is an exoskeleton? A hard outer covering. Which group of arthropods do flies Insects. belong to? Give an example of a mollusc. Snail.