introduction to cells and cell structure.pptx

Science

1. Year 7 Cells Context and Introduction to Unit In this unit pupils will learn about cells as the building blocks of all living organisms. Pupils will explore the use of and importance of microscopes. They will explore animal and plant cells, the components that make them up, their structure and function. In addition to this, they will explore specialised cells and what makes the specialised. Prior knowledge KS2 NC – Pupils should have had the opportunity to explore living and non living things in both Year 5 & 6 and explore features and characteristics of these which will support work on adaptations. They have also explored evolution and inheritance which will link to ideas about specialised cells. CORE KNOWLEDGE A unicellular organism is one which is made up of only one cell for example an yeast, bacteria and protozoa. Explore some of the structural adaptations of some unicellular organisms e.g. bacteria do not have a nucleus but they may have a flagellum. This is a tail-like part of the cell that can spin, moving the cell along Multi-cellular organisms are organised in layers and of the general structure: Cell – tissue – organs – organ system – organism Animal cells contain a nucleus (controls the cell and contains genetic info), cytoplasm (site where chemical reactions take place), cell membrane (allows substances in and out of the cell) and mitochondria (where respiration occurs and energy is released), whereas plant cells contain these plus a cell wall (provides strength and support), vacuole (contains cell sap and keeps the cell turgid) and chloroplasts (where photosynthesis takes place in plants). Microscopes are used to observe small objects in detail. The eyepiece lens and the objective lens can have different magnifications. Multiplying these together provides the total magnification and the greater the number, the greater the magnification. Prepare a slide for a microscope by swabbing the sample (cheek cell) or removing a think layer (onion cell) placing this on the slide and applying the correct indicator (cheek – methyl blue, onion – iodine), placing a cover slip over it and then carefully putting the slide on the stage of the microscope and gently moving the adjusting knob to focus in on the sample and observe. Specialised cells are those which are suited to carry out specific functions based on specific adaptations/features. These features are mainly structural but some features may be behavioural adaptations. Main specialised cells include sperm cell (tail to help swim, lots of mitochondria to transfer energy), red blood cell (no nucleus, disc like shape to increase surface are and carry more oxygen), root hair cells (root hair creates large surface area to absorb water), nerve cells (long and thin to transmit message around the body). ABOVE AND BEYOND Explore the term ‘ribosomes’ and their relative function within a cell. Extended magnification calculation questions based on GCSE expectations. VOCABULARY Cell Sperm cell Organelle Root Hair Cell Unicellular Microscope (etymology) Component Magnification (etymology) Nucleus (etymology) Cell membrane Cytoplasm Mitochondria Cell wall Vacuole Chloroplasts Respiration Photosynthesis Specialised Nerve cell Personal Development L iteracy Focus Compare the structure of animal and plant cells detailing the components in each. Disciplinary reading task – page from the activate text book. N umeracy focus Calculate magnification. WHERE NEXT? KS3 – Photosynthesis/respiration. Ks4 – Cell Biology, transport, cell division, mitosis. The bigger picture: Links to cell structure and division at KS4. This is in addition to exploring transport of substances in cells. Career link – botanist, cell biologist, virologist, microbiologist, any career in health care

2. Year 7 Cells: Assessment Plan M APs – Pupils will complete the following two WOW zone task (guidance and mark schemes can be found within the lesson resources): Compare the structure of animal and plant cells detailing the components in each. Disciplinary reading before completing the MAP. S ummative assessment – The knowledge from this unit will be tested as part of a 1 hour P2S exam which will combine the Biology, Chemistry and Physics curriculum covered so far. Assessment Steps Emerging Developing Securing Mastering Pupils have basic knowledge of cells: Pupils can identify an animal and plant cell. Pupils can name some cell components. Pupils must be have an understanding of and be able to recall the basics of cells: State the function of some cell components. Recall the similarities and differences between plant and animal cells. Pupils must be able to recall the following content: Levels of organsiation in order from smallest to largest. Cell – tissue – organs – organ system – organism Label key components of a plant and animal cell and state the the functions of the cell wall, cell membrane, cytoplasm, nucleus, vacuole, mitochondria and chloroplasts Label parts of a microscope and prepare a specimen to view under the microscope. Calculate magnification. Identify specialised cells and state how they are adapted to their role. Describing more than one adaptation/feature for several specialised cells. Describe the structural adaptations of some unicellular organisms. Describe how to observe and interpret cell structure a under a microscope. Explain why we always start with the lowest objective lens when viewing a specimen. Pupils should be able to recall all the content in the knowledge journey and demonstrate application through the following: Explore the term ‘ribosomes’ and their relative function within a cell. Extended magnification calculation questions based on GCSE expectations.