Life Sciences Grade 10 Limpopo June 2022 Paper & Memo

Downloaded from hlayiso.com NATIONAL SENIOR CERTIFICATE GRADE 10 LIFE SCIENCES JUNE EXAM 2022 MARKS: 150 TIME: 2½ HOURS This question paper consists of 15 pages

Downloaded from hlayiso.com Life Sciences / Gr 10 2 Limpopo PED/ June 2022 INSTRUCTIONS AND INFORMATION 1. Answer ALL the questions 2. Write ALL the answers in the ANSWER BOOK. 3. Start the answer to EACH question at the top of a new page 4. Number the answers correctly according to the numbering system used in this question paper. 5. Present your answers according to the instructions of each question. 6. Do ALL drawings in pencil and label them in black or blue ink. 7. Draw diagrams or flow charts only when asked to do so. 8. s.co The diagrams in this question paper are NOT necessarily drawn to scale. 9. Do NOT use graph paper. m 10. si Only a non-programmable calculator, protractor and a compass must be used c where necessary. st 11. Write neatly and legibly. an mor ep hy om fr oa de d do wn l Copyright reserved Please turn over

Downloaded from hlayiso.com Life Sciences / Gr 10 3 Limpopo PED/ June 2022 SECTION A QUESTION 1 1.1 Various options are provided as possible answers to the following questions. Choose the correct answer and write only the letter (A to D) next to the question number (1.1.1 to 1.1.10) in the ANSWER BOOK, e.g. 1.1.11 B 1.1.1 The organelle where proteins are synthesised: A nucleus s.co B ribosomes C cytosol m D mitochondria si c st an Questions 1.1.2- 1.1.4 are based on the figure below. mor ep hy om fr oa de d 1.1.2 Part R represents the: do A Enzyme wn B Active site l C Substrate D Catalyst 1.1.3 Part Q represents the: A Enzyme B Active site C Substrate D Amino acid Copyright reserved Please turn over

Downloaded from hlayiso.com Life Sciences / Gr 10 4 Limpopo PED/ June 2022 1.1.4 Which property of enzymes is illustrated by the diagram? A Enzymes are sensitive to temperature B Enzymes are protein in nature C Enzymes are sensitive to pH D Enzyme acts on one substrate only. 1.1.5 An inorganic constituent of protoplasm is…. A water B starch C cholesterol D haemoglobin 1.1.6 The organelle that plays a role in cell division is … A centrosome B vacuole C chloroplast D ribosomes 1.1.7 Cell division associated with growth in an organism, is called A asexual reproduction B budding C meiosis D mitosis .1.8 Companion cells in plants are distinctive of A phloem tissue B xylem tissue C chlorenchyma tissue D sclerenchyma tissue 1.1.9 A motor neuron carries a nerve impulse to… A a receptor B an effector C the brain D the cell body Copyright reserved Please turn over

Downloaded from hlayiso.com Life Sciences / Gr 10 5 Limpopo PED/ June 2022 1.1.10 Fluid mosaic model is a characteristic of………. A cell wall B tonoplast C nuclear membrane D cell membrane 10x2 = (20) 1.2 Give the correct biological term for each of the following descriptions. Write only the term next to the question number (1.2.1 to 1.2.7) 1.2.1 Swelling of thyroid gland due to lack of iodine. 1.2.2 Structure within the nucleus that contain genetic material 1.2.3 The structure that connects 2 chromosomes together during cell Division 1.2.4 Parenchyma cells that contain chloroplasts 1.2.5 Long, coil thread-like structures made up of DNA that are found in the nucleus 1.2.6 Vascular tissue that transport water present in the veins of the leaf 1.2.7 The structural and functional unit of life (7) Copyright reserved Please turn over

Downloaded from hlayiso.com Life Sciences / Gr 10 6 Limpopo PED/ June 2022 1.3 Indicate whether each of the statements in COLUMN 1, applies to A ONLY, B ONLY, BOTH A and B, or Neither A nor B of the items in column II. Write A only, B only, Both A and B, or Neither A nor B. COLUMN 1 COLUMN II 1.3.1 Strong bone and teeth A: Vitamin D development B: Calcium 1.3.2 Compound in which carbohydrates A: glycogen are stored in animal cells. B: starch 1.3.3 Tissue has a support function A: Epidermal tissue B: Collenchyma Tissue 1.3.4 Nutrients that are required in large A: micronutrient amount B: macronutrient (4x2) = (8) 1.4 Study the diagram below and answer the questions that follow. 1.4.1. Identify the tissue illustrated (1) 1.4.2. Name TWO processes in which this tissue is involved. (2) 1.4.3. Identify the parts numbered 1-5. Write the number and its label. (5) 1.4.4 State ONE ways in which the leaf is structurally suited for its function. (1) (9) Copyright reserved Please turn over

Downloaded from hlayiso.com Life Sciences / Gr 10 7 Limpopo PED/ June 2022 1.5 Study the diagrams below and answer the questions that follow. 1.5.1 Identify the process represented by the diagrams above. (1) 1.5.2 Give the number and the name of the tissue transporting organic food. (3) 1.5.3 Give the function of part (a) number 1 (1) (b) number 2 (1) (6) TOTAL SECTION A: 50 Copyright reserved Please turn over

Downloaded from hlayiso.com Life Sciences / Gr 10 8 Limpopo PED/ June 2022 SECTION B QUESTION 2 2.1 Study the table below which shows the composition of certain food types in the human diet per 100g units and answer the questions that follow. Food Energy Proteins Fats Carbo- Calcium Iron Vit A Vit C type (KJ) (g) (g) hydrates (mg) (mg) (Ug) (Ug) (g) Bacon 1983 18,0 52,0 0 15 0 0 0 Beans 376 7,0 0,4 22,0 65 2,4 298 0 Bread 1072 8,8 1,4 58,1 102 1,8 0 0 Butter 3230 0,2 87,3 0 1,7 0 2015 1,5 Milk 281 3,9 4,6 5,4 129 0,15 87 0,1 2.1.1 Which food type supplies the most in the nutritional needs of the body? Support your answer with evidence from the table. (3) 2.1.2 Which food type provides the most energy per unit mass? Justify your answer. (2) 2.1.3 Which of the food types above would be the most beneficial for? (a) growth and development (b) preventing Osteomalacia (c) normal night vision (d) preventing anaemia (e) preventing bleeding gums (5) Copyright reserved Please turn over

Downloaded from hlayiso.com Life Sciences / Gr 10 9 Limpopo PED/ June 2022 2.1.4 Certain washing powders are described as ’biological washing Powders’ because they contain enzymes. These washing powders are good for removing stains such as egg, chocolate, blood and gravy. In some instances these enzymes are obtained from a type of bacterium. These enzymes are somewhat unusual in that they work optimally (best) at a temperature of 60⁰C. (a) Why are these ‘ biological washing powders’ more effective Than ordinary washing powders at removing the types of stains Made by egg, chocolate, blood and gravy? (3) (b) Explain why is unusual for an enzyme to have an optimal temperature of 60⁰C. (3) (16) 2.2 The following diagram represents a type of nerve tissue. Study the diagram and answer the questions that follow. 2.2.1 What type of nerve tissue is illustrated above? (1) 2.2.2 What is the function of this type of nerve tissue in the human body? (4) 2.2.3 Identify the parts numbered 1 to 5 (5) 2.2.4 State ONE function of the parts numbered: (a) 5 (1) (b) 2 (1) (c) 6 (1) Copyright reserved Please turn over

Downloaded from hlayiso.com Life Sciences / Gr 10 10 Limpopo PED/ June 2022 2.2.5 What is the name of the site of contact between two consecutive nerve fibres? (1) (14) 2.3 Four measuring cylinders, A, B, C and D were set up as the one shown in the diagram. Each measuring cylinder contained a leafy twig and 80 ml water covered with a layer of oil. The four cylinders were left in the laboratory but were treated differently as follows:  Cylinder A : placed in wind  Cylinder B : placed in sunlight  Cylinder C : the leafy twig was covered in a clear plastic bag that was wet on the inside  Cylinder D : placed in shade After two hours, water levels in the four cylinders, A to D were recorded and the following results were obtained: Results: 1 2 3 4 45 ml 48 ml 50 ml 55 ml 2.3.1 Name the process that causes water to be lost from the twig. (1) 2.3.2 State the aim of this investigation. (2) 2.3.3 Explain the purpose of the oil layer? (2) Copyright reserved Please turn over

Downloaded from hlayiso.com Life Sciences / Gr 10 11 Limpopo PED/ June 2022 2.3.4 Explain ONE precaution that needs to be taken when using leafy twigs, to ensure the results are valid. (2) 2.3.5 Write down the letters A to represent the measuring cylinder. Using the results in the table above, calculate the amount of water loss you would expect for each of the four cylinders. (2) (9) 2.4 Study the accompanying diagram which shows the antagonistic muscles Of the upper arm in the human body. 2.4.1 Explain the term antagonistic muscles. (2) 2.4.2 Identify the muscles numbered: (a) 1 (1) (b) 2 (1) 2.4.3 When the hand is lifted in the direction of C, which muscle (1 or 2) will be: (a) The extensor (1) (b) The flexor (1) 2.4.4 Identify the bones labelled: (a) Number 3 (1) (b) Number 4 (1) (c) Number 5 (1) 2.4.5 Name two parts of the skeleton. (2) (11) TOTAL QUESTION 2: [50] Copyright reserved Please turn over

Downloaded from hlayiso.com Life Sciences / Gr 10 12 Limpopo PED/ June 2022 QUESTION 3 3.1 Study the diagram below and answer the questions that follow: 3.1.1 Identify the cell organelles X and Y (2) 3.1.2 Which metabolic process is associated with: (a) X (b) Y (2) 3.1.3 Each organelle has a network of membranes. Describe the molecular structure of one of these membranes (3) 3.1.4 Identify the parts numbered 1 and 2. (2) 3.1.5 Identify the gases A, B, C and D respectively. (4) 3.1.6 State the three structural suitability of organelle X. (3) (16) Copyright reserved Please turn over

Downloaded from hlayiso.com Life Sciences / Gr 10 13 Limpopo PED/ June 2022 3.2 The following diagram represents part of a cross section through an angiosperm root. 3.2.1 Describe how water enters the structure numbered 1 from the soil. (6) 3.2.2 Write down the NUMBERS and NAMES of the tissue through which water passes, until it reaches the xylem. (4) 3.2.3 Name the force which develops in the root and is believed to push water up the stem. (1) 3.2.4 State TWO ways in which structure numbered 5 is suited for its function. (2) 3.2.5 Name the two processes by which water moves from the epidermis through to the middle of the root. (2) (15) Copyright reserved Please turn over

Downloaded from hlayiso.com Life Sciences / Gr 10 14 Limpopo PED/ June 2022 3.3 The diagrams below show four stages of a cell undergoing Mitosis. Study the diagrams and answer the questions that follow: 3.3.1 Give the NUMBERS of the diagrams in the correct order in which they occur in this process. (2) 3.3.2 (a) Name the stage of mitosis visible in DIAGRAM 2. (1) (b) Explain what occurs in this stage. (3) 3.3.3 How many chromosomes will be present in each of the daughter cells shown above after the process is complete? (1) 3.3.4 Give THREE reasons why mitosis is biologically important (6) (13) Copyright reserved Please turn over

Downloaded from hlayiso.com Life Sciences / Gr 10 15 Limpopo PED/ June 2022 3.4.1 In an investigation to determine the influence of milk on the growth of mice, Mice of the same litter and with the same average mass, were divided into Two groups A and B. They were fed on the following diets for a 50 day Period. 3.4.1 Name TWO ways in how the scientist ensured the validity of the Investigation. (2) 3.4.2 What conclusion can you draw from the results of the experiment? (2) 3.4.3 Give the dependent variable in this investigation and how it was measured (2) (6) TOTAL QUESTION 3: [50] TOTAL SECTION B: 100 GRAND TOTAL: [150] Copyright reserved Please turn over

Downloaded from hlayiso.com NATIONAL SENIOR CERTIFICATE GRADE 10 LIFE SCIENCES JUNE 2022 MARKING GUIDELINE MARKS: 150 TIME: 2½ HOURS This MARKING MEMORANDUM consists of 10 pages

Downloaded from hlayiso.com Life Sciences/ Gr 10 2 Limpopo PED/ June 2022 MEMORANDUM PRINCIPLES RELATED TO MARKING LIFE SCIENCES 2022 1. If more information than marks allocated is given Stop marking when maximum marks are reached and put a wavy line and ‘max’ in the right hand margin. 2. If, for example, three reasons are required and five are given Mark the first three irrespective of whether all or some are correct/incorrect. 3. If whole process is given when only part of it is required Read all and credit relevant part. 4. If comparisons are asked for and descriptions are given Accept if differences / similarities are clear. 5. If tabulation is required but paragraphs are given Candidates will lose marks for not tabulating. 6. If diagrams are given with annotations when descriptions are required Candidates will lose marks. 7. If flow charts are given instead of descriptions Candidates will lose marks. 8. If sequence is muddles and links do not make sense Where sequence and links are correct, credit. Where sequence and links are incorrect, do not credit. If sequence and links become correct again, resume credit. 9. Non-recognized abbreviations Accept if first defined in answer. If not defined, do not credit the unrecognised abbreviation but credit the rest of answer if correct. 10. Wrong numbering If answer fits into the correct sequence of questions but the wrong number is given, it is acceptable. 11. If language used changes the intended meaning Do not accept. 12. Spelling errors If recognizable accept provided it does not mean something else in Life Sciences or if it is out of context. 13. If common names given in terminology: only accept if provided as an alternative in the marking guideline. 14. If only letter is asked for and only name is given (and vice versa) No credit. 15. If units are not given in measurements: Candidates will lose marks. Memorandum will allocate marks for units separately Copyright reserved Please turn over

Downloaded from hlayiso.com Life Sciences/ Gr 10 3 Limpopo PED/ June 2022 MEMORANDUM 16. Be sensitive to the sense of an answer, which may be stated in a different way. 17. Caption: All illustrations (diagrams, drawings, graphs, tables, etc.) must have a caption 18. Code-switching of official languages (terms and concepts) A single word or two that appears in any official language other than the learners’ assessment language used to the greatest extent in his/her answer should be credited, if it is correct. 19. No changes must be made to the marking memoranda without consulting the Provincial Internal Moderator. Copyright reserved Please turn over

Downloaded from hlayiso.com Life Sciences/ Gr 10 4 Limpopo PED/ June 2022 MEMORANDUM SECTION A QUESTION 1 1.1 1.1.1 B 1.1.2 B  1.1.3 C  1.1.4 D  1.1.5 A  1.1.6 A  1.1.7 D  1.1.8 A  1.1.9 B  1.1.10 D  10 x2 (20) 1.2 1.2.1 Goitre 1.2.2 Chromosome  1.2.3 Centromere  1.2.4 Chlorenchyma  1.2.5 Chromatin material  1.2.6 Xylem  1.2.7 Cell  (7) 1.3 1.3.1 Both A and B  1.3.2 A only  1.3.3 B only  1.3.4 B only  4x2 (8) 1.4 1.4.1 Epidermal tissue showing stoma/ of a leaf (1) 1.4.2 Photosynthesis Gaseous exchange/transpiration (2) 1.4.3 1. Thin outer wall  Copyright reserved Please turn over

Downloaded from hlayiso.com Life Sciences/ Gr 10 5 Limpopo PED/ June 2022 MEMORANDUM 2 Thick inner wall 3. Nucleus /chloroplast 4. Guard cells  5. Stoma, stomal pore (5) 1.4.4 It is flattened to provide a large surface area for maximum light absorption The cuticle and epidermis are transparent to allow light to enter the mesophyll region.  The palisade cells are arranged at right angles to the epidermis/ rod shaped to allow for maximum light absorption (Any 1) (2) (9) 1.5 1.5.1 Secondary growth 1.5.2 6; 8 Phloem (3) 1.5.3 (a) it divideds to form secondary xylem an phloem (1) (b) It trans-locates / stores water and dissolved ions/filling/ meristmatic function/secretion of tannins etc. or Lends support/packing/ strengthening (1) (6) TOTAL SECTION A: 50 Copyright reserved Please turn over

Downloaded from hlayiso.com Life Sciences/ Gr 10 6 Limpopo PED/ June 2022 MEMORANDUM QUESTION 2 2.1 2.1.1 Milk  It has all the nutrients needed by the body / that the body needs to function optimally (3) 2.1.2 Butter It has the highest fat content/contains the most energy (2) 2.1.3 (a) Bacon (b) Milk (c) Butter (d) Beans (e) Butter  (5) 2.1.4 (a) Stains contain organic compound (lipids, carbohydrates and proteins). Biological washing powders react with stains easily so can remove them due to the presence of enzymes. (3) (b) Enzymes are sensitive to high temperatures.  They usually denature at temperatures of 40-45⁰C and are not able to function at a temperature of 60⁰C. (3) (16) 2.2 2.2.1 Motor neuron  (1) 2.2.2 Motor neurons carry impulses from the brain / spinal cord to the effectors/ muscles or glands to bring about a response (4) 2.2.3 1. Nucleus 2. Myelin sheath / neurilemma 3. Axon 4. Cell body 5. Dendrite  (5) Copyright reserved Please turn over

Downloaded from hlayiso.com Life Sciences/ Gr 10 7 Limpopo PED/ June 2022 MEMORANDUM 2.2.4 (a) Receive and transmit impulses to the cell body  (b) Protects the axon  (c) Transmits impulse away from cell body/ transmits impulse to the effector organ/ muscle/forms synaptic knob/node with effector organ/ muscle (3) 2.2.5 Synapse (1) (14) 2.3 2.3.1 Transpiration  (1) 2.3.2 To determine the effect of different environmental conditions on the rate of transpiration.  (2) 2.3.3 Prevents evaporation of water  so that the final reading is reliable (2) 2.3.4 ● cut leafy twig under water  to prevent air from getting into the xylem tissue  make a diagonal cut  to increase the surface area of absorption of water   use twigs of the same size and species because a larger twig/ different type of species will have more leaves and will have a faster rate of transpiration/ will absorb the water faster (Any ONE) (2) 2.3.5 A: (Wind) 80 - 45 = 35 ml  (2) (9) 2.4. 2.4.1 A pair of muscles which work together to cause similar but opposite movement (2) 2.4.2 (a) Biceps (1) (b) Triceps (1) 2.4.3 (a) 2 (1) Copyright reserved Please turn over

Downloaded from hlayiso.com Life Sciences/ Gr 10 8 Limpopo PED/ June 2022 MEMORANDUM (b) 1 (1) 2.4.4 (a) Humerus (1) (b) Radius (1) (c) Ulna (1) 2.4.5 The axial skeleton and the appendicular skeleton (2) (11) TOTAL QUESTION 2: [50] QUESTION 3 3.1 3.1.1 X-mitochondrion Y-chloroplast (2) 3.1.2 (a) cellular respiration (b) photosynthesis (2) 3.1.3  Membranes consist of 2 layers of phospholipid molecules   Each phospholipid consists of a water-attracting (hydrophilic) head   and a water-repelling (hydrophobic) tail   The heads of both layers face outwards   and the tails of both layers face outwards   Proteins are embedded between the phospholipid molecules (Any) (3) 3.1.4 1-stroma  2-granum  (2) 3.1.5 A: Carbon dioxide / CO2 B: Oxygen /O2 C- Carbon dioxide /CO2 D- Oxygen / O2 (4) 3.1.6  has differentially permeable double membrane   outer membrane is smooth for easy movement through the cytoplasm  inner membrane is folded/ has cristae that increases surface area  Cristae coated with enzymes for maximum chemical reactions  Matrix contains compounds needed for cellular respiration process (Any) (3) (16) Copyright reserved Please turn over

Downloaded from hlayiso.com Life Sciences/ Gr 10 9 Limpopo PED/ June 2022 MEMORANDUM 3.2 3.2.1 - water potential in the soil is higher than that of the cell sap in the vacuole - water diffuses from soil along a water potential gradient - by osmosis through permeable cell wall and differentially permeable cell membrane /plasmalemma/ cytoplasm/tonoplast - into the vacuole of root hair - absorption of water is a passive process - and the water potential of cell sap increases (Any 6) (6) 3.2.2 2- parenchyma cells 3- endodermis 4- pericycle 5- xylem  (4) 3.2.3 Root pressure  (1) 3.2.4  The cells are elongated cells,/ where the cross walls disappear to form continuous tubes for the transport of water  Xylem tissue does not contain cytoplasm/ contains no living tissue so that the path of water is not blocked by the cytoplasm  The cellulose cell walls are strengthened with lignin,  to prevent them from collapsing under the strong suction pressure (Any 2 x2) (4) (15) 3.3. 3.3.1 3; 4; 1; 2  (MUST BE IN CORRECT ORDER) (2) 3.3.2 (a) Diagram 2: Telophase  (1) (b) Two groups of chromosomes are present A cell plate forms to separate the cell Into 2 distinct cells with their own nucleus  and the same number and kind of chromosomes (Any 3) (3) 3.3.3 4 chromosomes (1) 3.3.4 It forms new cells used for:  Growth in the size of the organism  Repair and replacement of work out or damaged tissue  Brings about asexual/ vegetative reproduction  (6) (13) Copyright reserved Please turn over

Downloaded from hlayiso.com Life Sciences/ Gr 10 10 Limpopo PED/ June 2022 MEMORANDUM 3.4.1 They used mice  From the same litter (1)  with the same average mass (1) 3.4.2 The increase in the average mass was because of the added 3cm3 milk to their diet (2) 3.4.3 Growth of mice Measuring the average mass of the mice every 5 days for 50 days (2) (6) TOTAL QUESTION 3: [50] TOTAL SECTION B: 100 GRAND TOTAL: [150] Copyright reserved Please turn over