Chapter 1: Cells – the Building Blocks of Life
1.1 Introduction When and how to use these pages The Introduction in the Student Book indicates some of the ideas and skills in this topic area that students will already have met from KS2 or from previous KS3 work, and provides an indication of what they will be studying in this chapter. Ideas you have met before is not intended to be a comprehensive summary of all the prior ideas, but rather to point out a few of the key ones and to support the view that scientific understanding is progressive. Even though students might be meeting contexts that are new to them, they can often use existing ideas to start to make sense of them. In this chapter you will find out indicates some of the new ideas that the chapter will introduce. Again, it isn’t a detailed summary of content or even an index page; its purpose is more to act as a ‘trailer’ and a way of generating interest among students. The outcomes, then, will be recognition of prior learning that can be built on and stimulation of students’ interest in finding out more. There are a number of ways these two pages can be used. You might, for example:
• Use the Ideas you have met before as the basis for a revision lesson as you start the first new topic. • Use Ideas you have met before as the centre of spider diagrams, to which students can add examples, experiments they might have done previously or things they found interesting.
• Make a note of any unfamiliar/difficult terms and return to these in the relevant lessons. • Use ideas from In this chapter you will find out to ask students questions such as: • Why is this important? • How could it be used? • What might we be doing in this topic?
Overview of the chapter In this chapter, students will learn about the structure and function of specialised plant and animal cells, organisation in multicellular organisms, different types and adaptations of unicellular organisms and how plants and humans are adapted to reproduce. They will explore linked processes, including diffusion, pollination, seed dispersal, menstruation and fertilisation. They will consider environmental factors in discussing the role of insects and reasons for their demise. This chapter offers opportunities for students to become familiar with the use of microscopes. They are encouraged to use 3-D models to explain the structures of different cell types. They will plan to collect evidence and present data on pollen-tube growth and evaluate the effectiveness of seed-dispersal mechanisms.They will explore validity and reliability of evidence in several contexts, including how different substances affect the developing foetus. They will discuss advantages and disadvantages of adapations in plants, encouraging reasoning, analysis and evaluation.
Obstacles to learning Students may need extra guidance with the following terms and common misconceptions:
• Nucleus A common misconception is that the nucleus in a cell is the same as the nucleus of an atom. • Pollination and fertilisation These may be used interchangeably by students to mean the same process. • Seed dispersal Students may think that this only occurs by wind. They may also get confused between seeds and pollen.
• Puberty Students may think this consists of set changes at particular times. • Growth A common misconception is that cells get bigger and bigger.
Key Stage 3 Science Teacher Pack 1
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