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StudyPacks STUDY. KS4 SCIENCE Cells Animal and Plant cells This Study Pack aims to cover: 1. Animal and plant cells 2. Bacteria and yeast 3. Specialised cells. SB20 Study Packs are prepared by Qualified Teachers and Specialists and are a complete range of comprehensive compiled resources based on the UK National Curriculum covering the Primary and Secondary Frameworks including SATs and GCSE examinations. Student Name Contents Cells Notes 2-5 Practice questions 6-12 Exam questions 13-25 Mark scheme 26-36 1 2 3 Cells and simple cell transport All living things are made up of cells. The structures of different types of cells are related to their functions. Animal cells and plant cells have features in common, such as a nucleus, cytoplasm, cell membrane, mitochondria and ribosomes. Plant and algal cells also have a cell wall, and often have chloroplasts and a permanent vacuole. Bacterial and yeast cells have different structures to animal and plant cells. Dissolved substances pass into and out of cells by diffusion. Animal and plant cells Function of cells which animal and plant cells have in common Part Function Nucleus Contains genetic material, which controls the activities of the cell Cytoplasm Most chemical processes take place here, controlled by enzymes Cell membrane Controls the movement of substances into and out of the cell Mitochondria Most energy is released by respiration here Ribosomes Protein synthesis happens here Plant cells also have extra parts: Extra parts of plant cells Part Function Cell wall Strengthens the cell Chloroplasts Contain chlorophyll, which absorbs light energy for photosynthesis Permanent vacuole Filled with cell sap to help keep the cell turgid Make sure you can label diagrams of animal and plant cells, like these: Generalised animal and plant cell 4 Bacterial cells and yeast Bacterial cells Structure of a salmonella bacterium cell A bacterium is a single-celled organism. A bacterial cell has a different structure to an animal or plant cell. It has cytoplasm, a membrane and a surrounding cell wall, but the genetic material in a bacterial cell is not in a distinct nucleus. Yeast Yeast is a single-celled organism. Like bacterial cells, yeast cells have cytoplasm and a membrane surrounded by a cell wall. But unlike bacterial cells, yeast cells have a nucleus. Cells and simple cell transport Specialised cells Cells may be specialised for a particular function. Their structure will allow them to carry this function out. Here are some examples: Examples of the functions of cells Cell Function Adaption Absorbs light energy for photosynthesis Packed with chloroplasts. Regular shaped, closely packed cells form a continuous layer for efficient absorption of sunlight. Absorbs water and mineral ions from the soil Long 'finger-like' process with very thin wall, which gives a large surface area. Leaf cell Root hair cell 5 Cell Function Adaption Fertilises an egg cell female gamete The head contains genetic information and an enzyme to help penetrate the egg cell membrane. The middle section is packed with mitochondria for energy. The tail moves the sperm to the egg. Contains haemoglobin to carry oxygen to the cells. Thin outer membrane to let oxygen diffuse through easily. Shape increases the surface area to allow more oxygen to be absorbed efficiently. No nucleus, so the whole cell is full of haemoglobin. Sperm cell Red blood cells You are likely to be given information, perhaps in a diagram, to help you to explain the adaptations of a particular cell type to its function. 6 Cell structures and functions Aims Cells are the building blocks of life – every animal and plant is made up of them. In this activity you will label the crucial parts of a cell and then match cells with their special features. It is important that you think about how the cell is adapted to do its job. Method Label the different parts of the animal cell and plant cell in the diagrams below. Use the words at the bottom of the diagrams to help. You will need to use some of the words twice. Chloroplast Nucleus Mitochondria Cell membrane Ribosomes Chloroplast Mitochondria Vacuole Nucleus Cell membrane Vacuole Cytoplasm Cell wall Cytoplasm Ribosomes Cell wall 7 Match the types of cell listed to the special features that each cell has in order to carry out its function. Type of cell Special features Red blood cell This cell has thin hairs on its outer surface to move mucus up the windpipe. Nerve cell This is a disc-shaped cell, with no nucleus. It contains haemoglobin that helps it to carry oxygen around the body. Sperm cell This long, thin cell transmits electrical impulses. It has a cell body at one end and thin projections at the other end. Ciliated epithelial cell This cell has a projection which gives it a larger surface area. This helps it to absorb water from the ground. Root hair cell This cell has a tail that can flex, which means that it can move along the fallopian tubes until it meets an egg cell. Cell structures and functions Label the different parts of the animal cell and plant cell in the diagrams below. 8 Complete the table to show the function of each type of cell and the special features it has to perform its function. Type of cell Function Special features Red blood cell Nerve cell Sperm cell Ciliated epithelial cell Root hair cell 9 Artificial life, but is it intelligent? Aims In May 2010 a group of scientists, headed up by Dr Craig Venter, developed the first synthetic life form. This has caused a stir. This could lead to important scientific developments but some believe it could pose threats that have not existed before. In this activity you will investigate what the team of scientists did and begin to form opinions on the positives and negatives of their work. Your task Do some research online to find information about the first synthetic living cell. You could start by searching for “synthetic cell” or “artificial life” on the BBC news website. Then answer the following questions, based on what you’ve read. During the development Craig Venter and his team used certain parts of a host cell in order to produce their synthetic life. Match up the part of the cell with the role it played. Mitochondria The production of proteins for the new cell occurred here. Nucleus Energy is released to make the proteins and to synthesise DNA. Ribosome The synthesised DNA was inserted through this into the yeast cell. Cell membrane The synthesised genome (set of genes) was put into this area of the cell where it was assembled into a chromosome. Why are Dr Craig Venter and his team working on this project? What do they want to accomplish? ………………………………………………………………………………………………………. ………………………………………………………………………………………………………. ………………………………………………………………………………………………………. ………………………………………………………………………………………………………. ………………………………………………………………………………………………………. Why do you think the team used yeast cells as the host cell? ………………………………………………………………………………………………………. ………………………………………………………………………………………………………. ………………………………………………………………………………………………………. ………………………………………………………………………………………………………. 10 What are some of the suggested dangers of the project? Can you think of any other ethical issues? ………………………………………………………………………………………………………. ………………………………………………………………………………………………………. ………………………………………………………………………………………………………. ………………………………………………………………………………………………………. ………………………………………………………………………………………………………. ………………………………………………………………………………………………………. ………………………………………………………………………………………………………. ………………………………………………………………………………………………………. Write a script for a radio programme explaining the work that Dr Craig Venter has carried out. You could include interviews with other scientists, ones who agree with his work and ones who do not. Your script should be between three and seven minutes long. ………………………………………………………………………………………………………. ………………………………………………………………………………………………………. ………………………………………………………………………………………………………. ………………………………………………………………………………………………………. ………………………………………………………………………………………………………. ………………………………………………………………………………………………………. ………………………………………………………………………………………………………. ………………………………………………………………………………………………………. ………………………………………………………………………………………………………. ………………………………………………………………………………………………………. ………………………………………………………………………………………………………. ………………………………………………………………………………………………………. ………………………………………………………………………………………………………. ………………………………………………………………………………………………………. ………………………………………………………………………………………………………. ………………………………………………………………………………………………………. ………………………………………………………………………………………………………. 11 Hunt the answer - cells Aims All living things are made up of cells. The structure of a cell is related to its function. There is lots of important information to know about cells and how substances move in and out of them. Once you have completed this activity you will have a good revision sheet for this chapter. Method 1 Below is a table of 15 questions with gaps for the answers. Spread around the room you will find the answers to the questions. As you find them, write them into the correct boxes. Question Answer Where in a cell does respiration take place? Where in a cell does photosynthesis take place? What happens on the ribosome? What does the cell membrane do? What features does a plant cell have that an animal cell does not? What special features does a root hair cell have? Which type of cell has visual pigment, a special chemical that changes in different colours of light? How is a fat cell adapted to its role? What type of cell has a tail to help it swim along the fallopian tube? 12 Exam questions Q1. The drawing shows the cell of a bacterium. (a) List A gives the four structures labelled on the diagram. List B includes information about each structure. Draw one line from each structure in List A to the correct information about the structure in List B. List A Structure List B Information (4) (b) Give two differences between an animal cell and the cell of a bacterium. 1 ..................................................................................................................... 13 2 ..................................................................................................................... (2) (c) The diagrams show cells containing and surrounded by oxygen molecules. Oxygen can move into cells or out of cells. Into which cell, A, B, C or D, will oxygen move the fastest? Write the correct letter, A, B, C or D, in the box. (1) (d) Complete the following sentence. Oxygen is taken into the cell by the process of ............................................. (1) (Total 8 marks) Q2. The diagram shows a bacterium. On the drawing, name the structures labelled A, B, C and D. (Total 4 marks) Q3. This question is about cells. (a) (i) The diagram shows a sperm cell. 14 Use words from the box to label parts A and B. cell membrane cytoplasm nucleus (2) (ii) The diagram shows a cell from a leaf. Give the letters of two parts of the leaf cell which would not be found in a sperm cell. and . (1) (b) Sperm cells have many mitochondria. Why do sperm cells need many mitochondria? Tick ( ) one box. Sperm cells are involved in fertilisation. Sperm cells are produced in very large numbers. Sperm cells need a lot of energy to swim. (1) (Total 4 marks) 15 Q4. (a) The diagrams show cells containing and surrounded by oxygen molecules. Oxygen can move into cells or out of cells. Into which cell, A, B, C or D, will oxygen move the fastest? Write your answer, A, B, C or D, in the box. (1) (b) Draw a ring around the correct word to complete each sentence. diffusion (i) Oxygen is taken into cells by the process of osmosis . respiration (1) breathing photosynthesis (ii) Cells need oxygen for . respiration (1) membranes (iii) The parts of cells that use up the most oxygen are the mitochondria . nuclei (1) diffusion (iv) Some cells produce oxygen in the process of photosynthesis . respiration (1) 16 (Total 5 marks) Q5. The diagram shows a group of muscle cells from the wall of the intestine. (a) On the diagram, use words from the box to name the structures labelled A, B and C. cell membrane cell wall chloroplast cytoplasm nucleus (3) (b) How are these muscle cells adapted to release a lot of energy? ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... (2) (Total 5 marks) Q6. The diagram shows a cell from the lining of the lung. This cell is specialised to allow gases to pass through quickly. (a) Use words from the box to label structures A, B and C. cell membrane nucleus chloroplast cytoplasm mitochondria (3) (b) (i) Which feature of this cell allows oxygen to pass through quickly? Put a tick ( ) in the box next to your choice. It is thin. It has a large nucleus. 17 It has many mitochondria. (1) (ii) Complete the sentence by drawing a ring around the correct answer in the box. diffusion Oxygen passes through this cell by osmosis respiration (1) (Total 5 marks) Q7. (a) Put a tick ( ) in the correct boxes in the table below to show which of the parts given are present in the cells and organisms listed. CYTOPLAS M NUCLEUS CELL WALL GENES Leaf mesophyll cell Sperm (2) (b) (i) What is the main job of a leaf mesophyll cell? ........................................................................................................................... ........................................................................................................................... (1) (ii) Explain one way in which the structure of the leaf mesophyll cell helps it to carry out its job. ........................................................................................................................... ........................................................................................................................... ........................................................................................................................... ........................................................................................................................... (2) (Total 5 marks) Q8. The diagram shows an animal cell. 18 (a) Name each labelled part and give its function. A Name ............................................................................................................... Function .......................................................................................................... ......................................................................................................................... B Name .............................................................................................................. Function ......................................................................................................... ........................................................................................................................ C Name .............................................................................................................. Function ......................................................................................................... ........................................................................................................................ (6) (b) (i) This plant cell also contains chloroplasts, a cell wall and a vacuole. Label each of these parts on the diagram. (ii) Give the function of these parts of a plant cell. (3) Chloroplast function ......................................................................................... 19 ........................................................................................................................... Cell wall function ............................................................................................. ........................................................................................................................... Vacuole function .............................................................................................. ........................................................................................................................... (3) (Total 12 marks) Q9. The drawing shows an animal cell, seen at a very high magnification using an electron microscope. (a) (i) Label a mitochondrion [plural = mitochondria]. (1) (ii) What happens in the mitochondria? .......................................................................................................................... (1) (b) (i) Name and label the structure where you would find chromosomes. (1) (ii) What are chromosomes made of? .......................................................................................................................... (1) (c) What controls the rate of chemical reactions in the cytoplasm? .................................................................................................................................... (1) (Total 5 marks Q10. The drawing shows a white blood cell ingesting a bacterium. 20 (i) Use words from the list to label the parts of the white blood cell. cell membrane cell wall cytoplasm nucleus vacuole (3) (ii) The scale shows that the white blood cell is 10 micrometres long. How long is the bacterium? Show your working. ................... micrometres (2) (Total 5 marks) Q11. The diagram shows a human sperm. Inside the tail of the sperm is a filament mechanism that causes the side to side movement of the tail, which moves the sperm. (a) Describe the function of the mitochondria and suggest a reason why they are arranged around the filament near the tail of the sperm. ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... (3) (b) Explain the significance of the nucleus in determining the characteristics of the offspring. ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... (2) (Total 5 marks) Q12. The diagrams show a cheek cell from a human and a leaf cell from a plant. 21 (a) The two cells have a number of parts in common. (i) On the cheek cell, label three of these parts which both cells have. (3) (ii) In the table, write the names of the three parts you have labelled above and describe the main function of each part. Part Function .................................. .................................. .................................. (3) (b) Blood contains white cells and red cells. State the function of each type of cell in the blood. White cells ................................................................................................................. ..................................................................................................................................... Red cells .................................................................................................................... ..................................................................................................................................... (2) (Total 8 marks) Q13. The drawing shows part of a root hair cell. (a) Use words from the list to label the parts of the root hair cell. 22 cell membrane cell wall cytoplasm nucleus vacuole (4) (b) The diagram shows four ways in which molecules may move into and out of a cell. The dots show the concentration of molecules. The cell is respiring aerobically. Which arrow, A, B, C or D represents: (i) movement of oxygen molecules; (ii) movement of carbon dioxide molecules? .................... .................... (2) (c) Name the process by which these gases move into and out of the cell. ..................................................................................................................................... (1) (Total 7 marks) Q14. The diagram shows an animal cell. 23 (a) (i) Name structures A and B by choosing the correct words from the box. cell membrane cell wall cytoplasm nucleus vacuole Structure A ....................................................................................................... Structure B ....................................................................................................... (2) (ii) Which structure named in the box controls the passage of substances in and out of the cell? ........................................................................................................................... (1) (b) Distance P to Q on the diagram is the diameter of the cell. This distance was measured on three cells using a microscope. The results were as follows: cell 1: 63 micrometres cell 2: 78 micrometres cell 3: 69 micrometres Calculate the average diameter of these cells. Show clearly how you work out your final answer. ..................................................................................................................................... ..................................................................................................................................... Average diameter = ................................... micrometres (2) (Total 5 marks) Q15. The diagram shows an animal cell. (a) Name each labelled part and give its function. A Name ............................................................................................................... Function .......................................................................................................... 24 ......................................................................................................................... B Name .............................................................................................................. Function ......................................................................................................... ........................................................................................................................ C Name .............................................................................................................. Function ......................................................................................................... ........................................................................................................................ (6) (b) (i) This plant cell also contains chloroplasts, a cell wall and a vacuole. Label each of these parts on the diagram. (3) (ii) Give the function of these parts of a plant cell. Chloroplast function ......................................................................................... ........................................................................................................................... Cell wall function ............................................................................................. ........................................................................................................................... Vacuole function .............................................................................................. ........................................................................................................................... (3) (Total 12 marks) 25 Mark scheme M1. (a) all four correct = 4 marks three correct = 3 marks two correct = 2 marks one correct = 1 mark extra line from a statement cancels the mark 4 (b) any two from: • nucleus • no cell wall • separate chromosomes 2 (c) A 1 (d) diffusion 1 [8] M2. A – cell membrane 1 B– cytoplasm 1 C– genes / genetic material / chromosome 1 D – cell wall 1 [4] M3. (a) (i) A cytoplasm accept clear indications 1 B nucleus 1 (ii) any two from: two required for 1 mark 26 • P • R • T accept lower case letters 1 (b) sperm cells need a lot of energy to swim 1 [4] M4. (a) A 1 (b) (i) diffusion 1 (ii) respiration 1 (iii) mitochondria 1 (iv) photosynthesis 1 [5] M5. (a) A nucleus 1 B (cell) membrane 1 C cytoplasm 1 (b) any two from: • (contain mitochondria • many (mitochondria) • respiration (occurs in mitochondria) 2 [5] M6. (a) A nucleus 1 B (cell) membrane 1 C cytoplasm 1 (b) (i) it is thin 1 (ii) diffusion 1 [5] 27 M7. (a) sperm mesophyll / / / / (all correct) / / x / (all correct) for 1 mark each 2 (b) (i) absorbs light/to produce food (allow reference to gaseous exchange) for 1 mark 1 (ii) e.g. has chlorophyll/chloroplasts has elongated shape to absorb light for 1 mark each 2 [5] M8. (a) A cytoplasm 1 where (chemical) reactions take place do not accept where cell functions take place 1 or carries/holds the organelles/named organelles / named chemicals (including nutrients) do not accept keeps the shape of the cell or contains water or presses out on the membrane allow: keeps cell turgid allows transport through the cell B membrane do not accept by themselves: protects cell gives shape 1 controls what enters/leaves the cell 1 or contains the cell/holds the cell together do not accept keeps harmful substances out or allows movement into and out of the cell C nucleus 1 contains the genetic material/DNA/genes/chromosomes do not accept: brain of the cell stores information/instructions tells cell what to do 28 or controls (the activity) of the cell 1 (b) (i) one mark for each correctly labelled part cell wall do not accept anything inboard of the inner edge vacuole accept anything inboard of transplant chloroplast: site of photosynthesis/ for photosynthesis accept word equation or balanced equation 1 cell wall: supports the cell/keeps the shape/keeps it rigid do not accept protects the cells 2 (ii) vacuole: acts as reservoir for water / chemicals/(cell)/sap 3 or keeps cell turgid/pushes content to edge or maintains concentration gradient or allows cell elongation (not growth) 1 [12] M9. (a) (i) award 1 mark for any of the mitochondria correctly labelled if a number are labelled and one is incorrect award 0 marks 1 (ii) respiration or the release or transfer of energy or it contains the enzymes for respiration do not accept energy produced 1 (b) (i) nucleus (named and correctly labelled) arrow or line must touch or go inside the nuclear membrane 1 (ii) DNA or genes or nucleic acids accept protein or histones or nucleotides or ATGC 1 (c) enzymes or nucleus do not accept factors that affect the rate rather than control it eg pH or temperature 1 29 M10. (i) cytoplasm (cell) membrane nucleus all correctly labelled each for 1 mark 3 (ii) 0.5 gains 2 marks (5/100 × 10 or ½ /1 gains 1 mark if 0.5 not given) 2 [5] M11. (a) award one mark for each key idea energy released or energy transferred or respiration allow provides or gives do not allow produces or makes 3 near to the site of movement or energy available quickly or more energy accept allows more mitochondria to fit in (mitochondria) packed (around filament) or efficient arrangement or spiral arrangement (b) contains chromosomes or genes or DNA not genetic material 1 (which) contribute half (the genes) to the fetus or offspring 23 chromosomes or half the genes or reference to X,Y chromosome determining sex (if the notion of halfness is there) nucleus contains half genes for the offspring = 2 marks 1 [5] M12. (a) (i) the three features correctly labelled on cheek cell (which are referred to in part (ii) label lines should touch or end very close to part no marks if leaf cell labelled nucleus cytoplasm cell membrane mitochondrion accept mitochondria or one of these could be labelled vacuole 3 (ii) any three from feature nucleus function controls cell 30 accept contains genetic material or genes or chromosomes or stores information do not credit the brain of the cell cytoplasm where respiration occurs accept contains food or mitochondria or reactions occurs membrane less water or chemicals accept surrounds the cell or lets some things in but not others do not credit keeps things out or protection in and or out mitochondria where energy released ecf from leaf cell labelling accept chloroplasts make sugar or glucose accept vacuole contains sap accept if cell wall mis labelled on cheek cell, support or hold together 3 (b) fight or ingest or kill bacteria or germs or viruses or microbes accept produce antitoxins or antibodies fight disease (organisms) do not credit fungus 1 (transport) oxygen or carry haemoglobin accept transport carbon dioxide or helps form scabs 1 [8] M13. (a) (cell) wall (cell) membrane cytoplasm vacuole for 1 mark each 4 (b) (i) A (ii) B for 1 mark each 2 (c) diffusion (reject osmosis) for 1 mark 1 [7] M14. (a) (i) A = nucleus 1 B = (cell) membrane 1 31 (ii) (cell) membrane 1 (b) 70 if correct answer, ignore working or lack of working for 1 mark 2 [5] M15 (a) A cytoplasm 1 where (chemical) reactions take place do not accept where cell functions take place 1 or carries/holds the organelles/named organelles / named chemicals (including nutrients) do not accept keeps the shape of the cell or contains water or presses out on the membrane allow: keeps cell turgid allows transport through the cell B membrane do not accept by themselves: protects cell gives shape 1 controls what enters/leaves the cell 1 or contains the cell/holds the cell together do not accept keeps harmful substances out or allows movement into and out of the cell C nucleus 1 contains the genetic material/DNA/genes/chromosomes do not accept: brain of the cell stores information/instructions tells cell what to do or controls (the activity) of the cell 1 (b) (i) one mark for each correctly labelled part cell wall do not accept anything inboard of the inner edge vacuole accept anything inboard of transplant chloroplast: site of photosynthesis/ for photosynthesis accept word equation or balanced equation 1 cell wall: supports the cell/keeps the shape/keeps it rigid do not accept protects the cells 2 32 (ii) vacuole: acts as reservoir for water / chemicals/(cell)/sap 3 or keeps cell turgid/pushes content to edge or maintains concentration gradient or allows cell elongation (not growth) 1 [12] Cell structures and functions answers Answers to questions Labelling the cell: 1 Cell membrane Mitochondria Cytoplasm Nucleus Ribosomes Cell wall Cell membrane Cytoplasm Mitochondria Chloroplast Nucleus Ribosome Vacuole 2 Matching up the cells with the features Red blood cell. This is a disc-shaped cell, with no nucleus. It contains haemoglobin that helps it to carry oxygen around the body. Nerve cell. This long, thin cell transmits electrical impulses. It has a cell body at one end and thin projections at the other end. Sperm cell. This cell has a tail that can flex, which means that it can move along the fallopian tubes until it meets an egg cell. Ciliated epithelial cell. This cell has thin hairs on its outer surface to move mucus up the windpipe. Root hair cell. This cell has a projection which gives it a larger surface area. This helps it to absorb water from the ground. Cell structures and functions Labelling the cells: 3 Cell membrane Mitochondria Cytoplasm Nucleus 33 Ribosomes Cell wall Cell membrane Cytoplasm Mitochondria Chloroplasts Nucleus Ribosomes Vacuole 4 Type of cell Function Special features Red blood cell Carries oxygen around the body Disc-shaped with no nucleus Nerve cell Transmits electrical impulses Long and thin with a cell body at one end and thin projections at the other end Sperm cell Fertilises the egg cell Has a tail that can flex to help it move along the fallopian tube Ciliated epithelial cell Moves mucus up the windpipe Has thin hairs on its outer surface to move the mucus Root hair cell Absorbs water from the ground Has a projection which gives it a large surface area to collect water Artificial life, but is it intelligent? Answers to questions During the development Craig Venter and his team used certain parts of a host cell in order to produce their synthetic life. Match up the part of the cell with the role it played. Mitochondria The production of proteins for the new cell occurred here. Nucleus Energy is released to make the proteins and to synthesise DNA. Ribosome The synthesised DNA was inserted through this into the yeast cell. Cell membrane The synthesised genome was put into this area of the cell where it was assembled into a chromosome. Why are Dr Craig Venter and his team working on this project? What do they want to accomplish? build cells that can remove carbon dioxide from the atmosphere build cells to produce useful products such as vaccines 34 build cells that could potentially act as fuel sources build cells that could offer new forms of communication make money? Why do you think the team used yeast cells as the host cell? easy to manipulate, easy and cheap to get hold of easy to grow and feed contain membrane bound organelles (unlike prokaryotes), no ethical issues with their use replicate rapidly. What are some of the suggested dangers of the project? Can you think of any other ethical issues? Bio-warfare and bio-terrorism are the main concerns. Other risks of genetically engineered organisms include a lack of understanding of what an organism that has never existed naturally could do, maintenance of our ecosystems, etc. The technology could fall into the wrong hands and, either intentionally or accidentally, could potentially pose a threat to human life. Hunt the answer – cells The task 1.Position the answer cards around the room. 2.Students have to go around the room and find the answers, then match them up with the correct questions and write them on their sheets. 3.This can then be followed up by a loop game – students split into groups (anywhere from three to six students) and divide the loop game cards up between them. The student who has the START card reads out their question and then the student who has the answer to that question reads out their answer and the question on their card. This continues in a loop until the students get back to the beginning. This can be made competitive by timing the groups to see who can finish fastest. Mitochondria Cell wall, chloroplast & a permanent vacuole Chloroplast Root hairs give a large surface area to absorb water and a large permanent vacuole to increase movement of water into the cell Production of proteins from amino acids Cone cells Controls the passage of substances in and out of the cell It can expand to 1000 its original size to store fat; it has a small amount of cytoplasm and few mitochondria Sperm cell 35 Question Answer Where in a cell does respiration take place? Mitochondria Where in a cell does photosynthesis take place? Chloroplast What happens on the ribosome? Production of proteins from amino acids What does the cell membrane do? Controls the passage of substances in and out of the cell What features does a plant cell have that an animal cell does not? Cell wall, chloroplast and a permanent vacuole What are the special features of a root hair cell? Root hairs stick out, giving a large surface area to absorb water and a large permanent vacuole to increase movement of water into the cell Which type of cell has visual pigment, a special chemical that changes in different colours of light? Cone cells How is a fat cell adapted to its role? It can expand to 1000 its original size to store fat; it has a small amount of cytoplasm and few mitochondria What type of cell has a tail to help it swim along the fallopian tube? Sperm cell 36