Agricultural Sciences Grade 11 North West June 2019 Memo

Downloaded from hlayiso.com PROVINCIAL ASSESSMENT GRADE 11 AGRICULTURAL SCIENCES MARKING GUIDELINE JUNE 2019 MARKS : 150 TIME : 2 ½ hours This MARKING GUIDELINE consists of 08 pages Demo Copyright reserve NW/JUNE/AGRSC/ EMIS/6*******

Downloaded from hlayiso.com SECTION A QUESTION 1 1.1 MULTIPLE CHOICE: 1.1.1 C 1.1.2 B 1.1.3 A 1.1.4 D 1.1.5 D 1.1.6 B 1.1.7 C 1.1.8 A 1.1.9 D 1.1.10 B (10 x 2) (20) 1.2 MATCHING COLUMNS: 1.2.1 A only  1.2.2 A only  1.2.3 B only  1.2.4 Both A and B 1.2.5 None  Demo NW/JUNE/AGRSC/ EMIS/6*******

Downloaded from hlayiso.com (5 x 2) (10) 1.3 AGRICULTURAL TERMS/ PHRASES: 1.3.1 Isomer  1.3.2 Atom  1.3.3 Adsorption/ Cation Adsorption  1.3.4 Atomic number  1.3.5 Haematite/ Iron  (5 x 2) (10) 1.4 CHANGING THE UNDERLINED WORD(S): 1.4.1 Polysaccharide  1.4.2 Electrons  1.4.3 Organic matter 1.4.4 Reserve acidity  1.4.5 Ammonification  (5 x 1) (5) TOTAL SECTION A: [45] SECTION B QUESTION 2 2.1.1 Organic Compounds A. Water Molecule  (1) B. Hydrogen Molecule  (1) 2.1.2 A water molecule  Polar covalent bond (1)  Unequal sharing of valence electrons/ Sharing of pair of electrons between atoms (1) B hydrogen molecule  Non – polar covalent bond  (1)  Equal sharing of pair of electrons between atoms (1) Demo NW/JUNE/AGRSC/ EMIS/6*******

Downloaded from hlayiso.com 2.1.3 Chemical formula for compound A (Water)  H2O  (2) 2.1.4 Functions of Compound A (Water)  Water is a solvent/ dissolve mineral salts to be absorbed by plants  Chemical reactions take place in water eg. Photosynthesis  Transport medium/ Substances dissolved in water can be transported around the body  Body form or shape and support/ Cytoplasm of cells consists mainly water  Regulate or control body temperature  Needed for reproduction any 3 (3 x 2 = 6) 2.2.1 Difference between  Hydrophobic: means something that does not like water/ will not readily mix or bond with water  Hydrophillic: means something that likes water/ will readily mix or be attracted to water (2 x 2 = 4) 2.2.2 Types of fatty acids  Saturated  Poly – unsaturated   Mono – unsaturated  (3 x 1 = 3 2.3. Table of Organic and Inorganic compounds A NH3 B Inorganic compound C Methane H D H C H H E Carbon dioxide F  G C2H5OH Demo NW/JUNE/AGRSC/ EMIS/6*******

Downloaded from hlayiso.com H H H H—C— C— OH H H I Ethanoic Acid J CH3COOH (1 x 10 = 10) 2.4.1 Disaccharides  Maltose (1)  Sucrose (1)  Lactose  (1) 2.4.2 Glycosidic bond (1) [35] QUESTION 3 ( SOIL SCIENCES) 3.1 Using texture triangle to determine soil textural class A. Silt – Loam  B. Loam C. Sand Clay – loam D. Clay – Loam  (8 3.2.1 Soil structure A. Platy : Thin, flat plates of soil that lie horizontally/ and usually found in compacted soil (2) B. Prismatic: Columns or units which are vertically longer than they are broad/usually found in lower horizon (2) C. Blocky : Irregular blocks that are having sharp angles and sides/ mostly found in the B - Horizon (2) 3.2.2 Factors influencing the development and stability of soil structure:  Soil structure and the colloidal matter of the soil  Type of clay mineral  Climate  Alternating moisture and drought  Plant roots Any 3 (3) 3.3 Bulk Density 3.3.1 Calculation of bulk density Bulk density = 750 g 500 cm3 Bulk density = 1, 5 g / cm3 (3) Demo NW/JUNE/AGRSC/ EMIS/6*******

Downloaded from hlayiso.com 3.3.2 Low bulk density because it is below 1. 6g/ cm3 the bulk density is ideal for plant growth/ or low bulk densities are an indication of favourable soil condition for cultivation (3) 3.4. 1 Movement of water and air in sand and clay soil  Sand – water movement very rapidly downward, aeration is good (2)  Clay – water movement extremely slow, aeration very limited (2) 3.4.2 Ways to increase the percentage of pore space in the top soil  Ensure a good soil texture/ the coarser the soil texture, the more total pore space  Ensure a good soil structure  Limit the cultivation of soil Any 2 (2) 3.4.3 The type of water in point labelled A  Gravitational water (1) 3.4.4 Forms of water present in the soil  Adhesion water (1)  Cohesion water (1) 3.5. Soil colour 3.5.1 Light colour or whitish colour (1) 3.5.2 Yellow colour (1) 3.5.3 Mottled colour (1) [35] QUESTION 4: SOIL SCIENCES 4.1.1 Factors that influence soil temperature labelled A – D A Slope/ topography/ orientation of the land/ aspect (1) B Degree of cloud covers (1) C Vegetation/ plant cover (1) D Soil depth (1) 4.1.2 Ways in which soil temperature influence plant growth  Seed germination is affected by soil temperature  Root growth depends on soil temperature  Soil microbes are active if temperatures are favourable/ release more nutrients for crops  any two (2 x 2 = 4) 4.2.1 Soil horizon which consists of clay/ or iron, manganese and aluminium oxides  B – horizon  (1) 4.2.2 Properties of G – horizon  G – horizon results from waterlogged condition  Soil which reflects permanent waterlogging  Wet or waterlogged horizon any 2 (2) 4.2.3 Reasons for the classification of soil  Optimal utilisation of land/ effective use of land  Homogeneous production units  Choice of crop Demo NW/JUNE/AGRSC/ EMIS/6*******

Downloaded from hlayiso.com  Planning of farming activities/ scientific farm planning  Allocation of land/ for agricultural purpose/ forestry/ game reserves  Valuation of soil/ used to value land when applying for a loan any two (2) 4.2.4 Levels of taxonomic soil classification system used in South Africa  Soil forms (1)  Soil families (1) 4.3.1 Group of micro – organisms in the soil  Bacteria  Fungi  Algae  Protozoa  Actinomycetes any 2 (2) 4.3.2 Beneficial effects of micro – organisms  Breakdown plant and animal remains to release plant nutrients  Form humus which improve soil structure and water retention  Release CO2 in the atmosphere during decay of plant materials  Help to turn milk into dairy products – sour milk, yoghurt, cheese  Help during fermentation of grape sugar to produce wine any 2 (2) 4.3.3 Micro – organism that plays a role in denitrification  Species of bacteria (Pseudomonas and achromobacter)  (1) 4.4.1 Graph showing different percentages of soil components Soil component Demo NW/JUNE/AGRSC/ EMIS/6*******

Downloaded from hlayiso.com Marking of Bar graph: Criteria Yes No Bar graph 1 0 Heading/ Title 1 0 Correct labelling of X-axis 1 0 Correct labelling of Y-axis 1 0 Indication of unit 1 0 Accuracy 1 0 4.4.2 Component that forms the most part of the soil  Rock particles (1) 4.5.1 Identifying the acidity and alkalinity of soil colloid based on adsorbed cations: A. Acid soil (1) B. Brackish (1) 4.5.2 Table to compare the saline and sodic soils under: Saline soil Sodic soil pH condition Less than 8, 5 Between 8, 5 and 10 Dominant salts Ca++ and Mg++ Na+ Surface appearance White brack or salt Black crust crystal crust Corrective measures Over – irrigation to leach Over – irrigation to leach out Out salts salts Improve drainage Apply gypsum Any three of the above mentioned (3 x 2 = 6) [35] TOTAL SECTION B [105] GRAND TOTAL [150] Demo NW/JUNE/AGRSC/ EMIS/6*******