The City School PAF Chapter

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1 The City School PAF Chapter Comprehensive Worksheet Answer Key May 2015 SCIENCE Class 7 The City School / PAF Chapter/ Comprehensive Worksheet/ May 2015/ Science/ Class 7 / Ans Key Page 1 of 6

2 SECTION A Objective [ /50] Q.1 Encircle the best option. [ /30] 1) Plant cell 2) nucleus 3) chromosomes 4) cellulose 5) trachea 6) carry as much oxygen as possible 7) tissue 8) circulatory system 9) nucleus 10) in form of rays 11) Bounces back 12) blue, green, red 13) 300,000,000 m/s 14) and blue 15) VIBGYOR 16) One year 17) when it enters from denser to lighter medium 18) Converging lens 19) Magnified image 20) Newton 21) Saturated solution 22) alkali 23) acidic 24) good electrical conductors 25) accurate 26) only 7 27) alkali 28) pink 29) plants 30) hydrogen The City School / PAF Chapter/ Comprehensive Worksheet/ May 2015/ Science/ Class 7 / Ans Key Page 2 of 6

3 Q.2 Give scientific reasons for the following. [10 Marks] 1. Light is blocked by an opaque object. 2. Sunlight is refracted, reflected and refracted again through a rain droplet so this happens. 3. When white light passes through aprism it splits up into its component colours. 4. So that substances can go in and out of the cell 5. Spikes get attached with the fur of passing by animals and are dispersed. Q.3. Mention true and false. Write correct statement for the false one. [10 Marks] 1) True 2) False. Appears red in red light 3) False. Plants are called as producers as they make their own food. 4) False. Omnivores eat plants and animals both. 5) False. Complex eye 6) False. Two types of cells 7) False.diaphragm 8) True 9) False.red filter transmits red colour and absorbs the rest 10) False. Plants depend upon animals for seed dispersal SUBJECTIVE Q.1(a). Reshma drew the following food web after studying a field [50 Marks] [6 Marks] 2 marks for each correct answer i. There will more butterflies because fewer will be eaten by blackbirds ii. iii. There will be fewer hawks because there will be fewer frogs as food for hawks. There will be fewer foxes because more frogs will eat more worms, leaving fewer worms for shrews, so there will be fewer shrew as food for foxes. (b) Jane studied the following habitat For each speciman,stste which habitat you think jane collected it from. Q.2 each part is of 1 mark. a) Wood b) Moorland c) Stream [ 3 Marks] The City School / PAF Chapter/ Comprehensive Worksheet/ May 2015/ Science/ Class 7 / Ans Key Page 3 of 6

4 ( c) [ 4 Marks] a) It changes its fur colour from brown to white. b) White camouflages it against the snow. c) It doesn t snow very often in Derbyshire. d) There is more heather to eat in the mountains. Or The mountain hare is better adapted to the snow in the mountains. Q.2(a) The shows leavesfrom different plants.choose a leaf to match each description of an adaptation below. [3 Marks] i. C ii. B iii. A (b) Write some features of the following animals which show how do they adapted to their habitat. [5 Marks] any logical answer is acceptable. 2 marks each ans. a) has gills so that it can breathe in water,streamlined body fish b) has a thick skin to keep in water,broad feet elephant c) has lots of body fat to keep warm,flippers penguin d) has feathers to make it streamlined, good eyesight bird e) has long legs and a poison gland to kill its prey spider Q.3-(a) What type of an image is formed by: [ 6 Marks] Concave mirror Magnified image Upside image Convex mirror Real image Upright image Virtual image Diminished image (b) How does refraction of light takes place? Explain. [2 Marks] When light travels from one medium to another at an angle, its speed changes so does its angle. This phenomenon is called as refraction. (c) Complete the table below. [2 Marks] The City School / PAF Chapter/ Comprehensive Worksheet/ May 2015/ Science/ Class 7 / Ans Key Page 4 of 6

5 Some further examples: Object socks teddy camel Magenta book Colour of light Colour object seems to be Black Black Black teddy- blue light-blue light- black camel red light- black light- black light- green Magenta book- red light blue light- red light- black (d) Complete the following table. (0.5 Mark each) [3 marks] Nucleus- controls all the activities of the cel Chloroplast- absorbs light to make food for the plant Cell membrane- controls what goes in and out of the cell Cell wall-protects the cell from bursting out,gives strength to the cell Cytoplasm- jelly like part of the cell where all the chemical reactions of the cell take place Vacuole-contains cell sap The City School / PAF Chapter/ Comprehensive Worksheet/ May 2015/ Science/ Class 7 / Ans Key Page 5 of 6

6 Q.4(a) Complete the following Venn diagram and mention the similar and different parts of an animal cell and a plant cell. [2 Marks] Features of animal cell-nucleus, cytoplasm, cell membrane Features of plant cell- nucleus, cytoplasm, cell membrane, chloroplst, cell wall, large central vacuole Same feature of both cells- nucleus, cytoplasm, cell membrane (b) Label the following six parts of the microscope. [6 Marks] 1-Focussing knob, 2-stage clips, 3- base, 4-eye piece lens, 5- objective, 6-diaphragm (c) Complete the following table. [5 marks] Name Of System Organs of the system Function Nervous System Brain,spinal cord, nerves Control the body, senses, emotions, thoughts Digestive System Blood Circulatory System Oesophagus,stomach,small and large intestines,liver, pancreas Heart, arteries, veins, capillaries Digest the food and obtain the energy from it Transport blood around the body Skeletal system Skull, backbone,limbs Give support to the body, help in movement Muscular system muscles Make the body move (d) Write the functions of following. [3 Marks] a) Connective tissue- helps in connecting different tissues in an organ b) Root hair cell-absorb water, minerals and salts from the soil c) Ground tissues-give support to plant, photosynthesis, storing food The City School / PAF Chapter/ Comprehensive Worksheet/ May 2015/ Science/ Class 7 / Ans Key Page 6 of 6