Geography Paper 1 Questions and Answers - Form 3 End Term 3 Exams 2021

INSTRUCTIONS.

• Answer ALL the questions

1.  
   1. What is desertification? (2mks)
   2. State three negative effects of desertification. (3mks)
2.  
   1. Describe the solar system. (2mks)
   2. Use the diagram below to answer the questions that follow.
               
   3. 1. What type of an eclipse is represented by the diagram? (1mk)
      2. Name the features marked L and M. (2mks)
3.  
   1. Identify two causes of earth movement. (2mks)
   2. The diagram below shows some features formed as result of faulting.
               
      
      1. Identify the angle marked J. (1mk)
      2. Identify the features marked K and L. (2mks)
4.  
   1. Apart from water vapour, name two other substances that are suspended in the atmosphere. (2mks)
   2.  
      1. Give two features that are considered when classifying clouds. (2mks)
      2. Name one type of cloud that give rise to rainfall in the tropical regions. (1mk)
5.  
   1. Give three causes of earthquakes. (3mks)
   2. Name two major earthquake zones of the world. (2mks)

SECTION B
Answer question 6 and any other two questions from this section.

6. Study the map of Kitale 1:50,000 (sheet 75/3) provided and answer the following questions.
   1.  
      1. Identify two human made features found at the grid square 3319. (2mks)
      2. Identify the altitude of the highest point in the area covered by the map. (2mks)
      3. What is the magnetic variation of the map? (1mk)
   2.  
      1. Measure the distance of the dry weather road (C640) from the junction at point M(345142) to the junction at point N (416201) give your answer in kilometers. (2mks)
      2. Draw a square 10cm by 10cm to represent the area enclosed by easting 36 and 46 and northings 13 and 23. (1mk)
         On the square mark and name the following. (4mks)
         1. Forest
         2. Plantation
         3. River Naigameget
         4. Dry weather road (C640)
   3. Describe the drainage of the area covered by the map. (5mks)
   4. Identify two social services offered in Kitale municipality. (2mks)
   5. Citing evidence from the map explain three factors that favour agricultural activities. (6mks)
7.  
   1.  
      1. Outline two factors that influence the development of drainage patterns. (2mks)
      2. Outline five characteristics of a river in its youthful stage. (5mks)
   2. Describe the following processes of river erosion.
      1. Attrition (2mks)
      2. Corrosion (4mks)
   3. Explain three negative effects of rivers to the human environment. (6mks)
   4. Your class is planning to carry out a field study of a river in its old stage.
      1. State three reasons why it would be necessary to pre-visit the area of study. (3mks)
      2. State three activities you would carry out to determine why deposition occurs at this stage. (3mks)
8.  
   1. Name the first two planets of the solar system. (2mks)
   2. Explain the origin of the earth according to the Nebula cloud theory. (8mks)
   3. Use the map below to answer questions (c ) (i)
               
      
      1. Name:
         The continent marked W. (1mk)
         The ocean marked X (1mk)
         The line of longitude marked Y. (1mk)
      2. Give two reasons why the earth has a spherical shape. (4mks)
      3. State four effects of the rotation of the earth on its axis. (4mks)
   4. Describe the structure of the earth’s crust. (4mks)
9.  
   1. Name two major deserts found in Africa. (2mks)
   2. The diagram below represents features resulting from wind erosion in a desert. Use it to answer question a.
               
      
      1. Name the features marked U and V. (2mks)
      2. Describe three processes through which wind transports its load. (6mks)
      3. Using a well labeled diagram, describe how a barchans is formed. (7mks)
      4. Explain four ways in which desert features are significance to human activities. (8mks)
10.  
    1.  
       1. Name three types of faults. (3mks)
       2. Apart from compressional forces explain two other processes that may cause faulting. (4mks)
    2. With the aid of diagrams, describe how compression forces, may have led to the formation of Great Rift Valley. (8mks)
    3. Explain five ways in which faulting is of significance to human activities. (10mks)

MARKING SCHEME

1.  
   1. What is desertification? (2mks)
      • Encroachment of arid conditions into formerly productive areas.
   2. State three negative effects of desertification. (3mks)
      • Leads to shortage of water
      • Drying up of vegetation
      • Leads to development of infertile soils
      • Population migrate out of an area affected by desertification
2.  
   1. Describe the solar system. (2mks)
      • Refers to the sun ,the planets and other heavenly bodies orbiting around it.
   2. Use the diagram below to answer the questions that follow.
      1. What type of an eclipse is represented by the diagram? (1mk)
         • Solar eclipse/eclipse of the sun
      2. Name the features marked L and M. (2mks)
         • L – The moon
         • M – umbra/moon shadow / lunar shadow
3.  
   1. Identify two causes of earth movement. (2mks)
      • Magma movement within the crust
      • Gravitational pull / gravitational pressure
      • Convectional currents in the upper mantle
      • Isostatic adjustment
   2. The diagram below shows some features formed as result of faulting.
      1. Identify the angle marked J. (1mk)
         • Hade
      2. Identify the features marked K and L. (2mks)
         • K – Tilt block
         • L – Fault scarp/ escarpment
4.  
   1. Apart from water vapour, name two other substances that are suspended in the atmosphere. (2mks)
      • Dust -pollen grains
      • Smoke - salt particles
      • Gases
      • Clouds
   2.  
      1. Give two features that are considered when classifying clouds. (2mks)
         • Altitude
         • Appearance
         • Formation
         • Structure
      2. Name one type of cloud that give rise to rainfall in the tropical regions. (1mk)
         • Cumulus
         • Cumulo – nimbus
         • Nimbus
5.  
   1. Give three causes of earthquakes. (3mks)
      • Movement of magma within the earth’s crust/ volcano eruptions.
      • Folding / faulting
      • Isostatic adjustment
      • Blasting of rocks leading to tremors
      • sudden energy release in the mantle
   2. Name two major earthquake zones of the world. (2mks)
      • Mediterranean belt -Rift valley/faulted areas
      • Circum pacific belt

SECTION B

6. Study the map of Kitale 1:50,000 (sheet 75/3) provided and answer the following questions.
   1.  
      1. Identify two human made features found at the grid square 3319. (2mks)
         • Road loose surface
         • Settlement
      2. Identify the altitude of the highest point in the area covered by the map. (2mks)
         • 2362 metres
      3. What is the magnetic variation of the map? (1mk)
         • 2O23’
   2.  
      1. Measure the distance of the dry weather road (C640) from the junction at point M(345142) to the junction at point N (416201) give your answer in kilometers. (2mks)
         • 12.1 km+ 0.1km
      2. Draw a square 10cm by 10cm to represent the area enclosed by easting 36 and 46 and northings 13 and 23. (1mk)
         On the square mark and name the following. (4mks)
         1. Forest
         2. Plantation
         3. River Naigameget
         4. Dry weather road (C640)
   3. Describe the drainage of the area covered by the map. (5mks)
      • The main drainage features are rivers.
      • Most rivers forms a dendritic drainage pattern with their tributaries.
      • There are swamps on the western part of the area covered by the map.
      • Main permanent rivers are kaptarit and kaitobos.
      • The area has many permanent rivers.
      • There are dams on the area covered by the map.
   4. Identify two social services offered in Kitale municipality. (2mks)
      • Health/medical services
      • Recreational services
      • Religious services
      • Security services
   5. Citing evidence from the map explain three factors that favour agricultural activities. (6mks)
      • High rainfall evidenced by many rivers, high rainfall offer suitable condition for the growth of many crops.
      • Transport evidenced by many roads that facilitates transportation of agricultural products from farms to the market.
      • Labour evidenced by dense settlements in save parts which facilitates most activities through the year.
      • Gentle slope evidenced by spaced contours in some parts of the area covered by the map which is ideal for mechanization in the farms.
7.  
   1.  
      1. Outline two factors that influence the development of drainage patterns. (2mks)
         • Direction of the slope of the land
         • Difference in rock resistance
         • Faulting
      2. Outline five characteristics of a river in its youthful stage. (5mks)
         • River has steep river gradient
         • River channel is narrow
         • River has u-shaped valleys
         • High stream velocity
         • Vertical erosion is dominant
         • Erosion features are common
         • River channel is generally straight /winding
   2. Describe the following processes of river erosion.
      1. Attrition (2mks)
         • As rock materials are transported down streams they constantly collide with each other. The materials gradually wear down/reduce in size.
      2. Corrosion (4mks)
         • As solid materials are transported downstream they are hurled – against the banks and dragged along the river bed.
         • The rock materials chip off pieces of rock from the channel and river bed.
         • The rock erodes the river bed.
         • Eddy currents rotate pieces of rocks around the hollows grinding on the river bed.
   3. Explain three negative effects of rivers to the human environment. (6mks)
      • When rivers flood, they may destroy property, lead to loss of life.
      • Wide and deep rivers a barrier to transport especially where bridges have not been constructed.
      • River can be contaminated from farm and homes thus spreading water-borne diseases.
      • Some rivers are habitat to dangerous animals which may attack human beings/destroy crops.
   4. Your class is planning to carry out a field study of a river in its old stage.
      1. State three reasons why it would be necessary to pre-visit the area of study. (3mks)
         • It helps to access suitability of the study early.
         • Helps to draw up objectives for the study.
         • Helps to draw a route map.
         • Helps to design a working schedule.
         • Helps to identify the problems and how to solve them in advance.
         • Helps to identify suitable methods of data collection.
      2. State three activities you would carry out to determine why deposition occurs at this stage. (3mks)
         • Measuring of the gradient
         • Finding out the nature of the load.
         • Finding out the amount of the load.
         • Establishing the velocity of the river
         • Observing obstacles in the stream.
         • Measuring the depth/width of the river.
8.  
   1. Name the first two planets of the solar system. (2mks)
      • Mercury
      • Venus
   2. Explain the origin of the earth according to the Nebula cloud theory. (8mks)
      • There was an explosion of a huge cloud of gases and dust.
      • This cloud whirled, condensed to a disc shape.
      • The gravitational attraction within the material caused the particles to compact.
      • The whirling caused particles to collide losing a little energy at a time.
      • The middle of the spinning disc condensed to form the sun while material spinning around condensed into large chunks of materials called planetoids.
      • The planetoids collided and condensed into large bodies called planets.
      • The earth is one of the planets.
      • The centre of the disc formed the sun.
   3. Use the map below to answer questions (c ) (i)
      1. Name:
         The continent marked W. (1mk)
         W - Asia
         The ocean marked X (1mk)
         X - Atlantic
         The line of longitude marked Y. (1mk)
         Y – prime meridian / greenwhich meridian
      2. Give two reasons why the earth has a spherical shape. (4mks)
         • The north and southern pole experience centripetal force which constantly pulls towards each other causing flattening at the poles.
         • The earth experience the centrifugal force which causes the bulge at the equator.
         • The earth experience force of gravity pulling towards the centre which creates a rounding effect on its shape.
      3. State four effects of the rotation of the earth on its axis. (4mks)
         • Causes day and nights
         • Causes deflection of winds and ocean currents
         • Causes difference of one hour between two meridians 15O apart.
         • Causes falling and rising of ocean tides.
         • Causes difference of speed of air masses.
   4. Describe the structure of the earth’s crust. (4mks)
      • Rocks are solid
      • Divided into two layers sial and sima
      • Sial rests on sima
      • Sial contains mainly silica and aluminum.
      • Sima contains mainly silica and magnesium.
      • Sima is denser that sial
      • Sial is less denser that sima.
9.  
   1. Name two major deserts found in Africa. (2mks)
      • Sahara
      • Karahari
      • Namib
   2. The diagram below represents features resulting from wind erosion in a desert. Use it to answer question a.
      1. Name the features marked U and V. (2mks)
         • U – furrow
         • V – ridge
      2. Describe three processes through which wind transports its load. (6mks)
         • Saltation: it is where coarse grained sand particles are transported through bouncing along the surface.
         • Suspension: is where fine material is picked by wind raised high and blown over long distances.
         • Surface creep: it is where large/heavy materials are rolled /pushed forward by wind along the surface.
      3. Using a well labeled diagram, describe how a barchans is formed. (7mks)
                  
         
         • It develops in arid areas when sand accumulates around an obstacle that lies in the path of the wind.
         • The gradual accumulation of sand forms a hill.
         • Eddy currents on the leeward side of the dune causes the formation of a steep slope.
         • With time, the prevailing wind forces the sand at the edge of the dune to move forward forming horns.
         • The continuous extension of horns lead to a crescent shaped feature called a barchans.
           (text 4 diagram 3)
      4. Explain four ways in which desert features are significance to human activities. (8mks)
         • Desert features form good site for tourist attraction earning foreign exchange.
         • Wind deflation hollow/oasis are sources of water for domestic/agriculture use.
         • Wind deposits fertile soils for farming.
         • Salty Salinas are exploited for salt production.
         • Arid areas are ideal for military training.
10.  
    1.  
       1. Name three types of faults. (3mks)
          • Normal fault
          • Reverse fault
          • Tear/shear fault
          • thrust fault
          • ant clinical fault
       2. Apart from compressional forces explain two other processes that may cause faulting. (4mks) 
          • Faulting may be caused by forces acting horizontally away from each other which causes tension in crystal rocks. Due to tensional force the rocks stretch and fracture causing faults.
          • Faulting may result when horizontal forces act parallel to each other in the same direction causing shearing.
          • Faulting may recur due to vertical movement which may exert a strain
    2. With the aid of diagrams, describe how compression forces, may have led to the formation of Great Rift Valley. (8mks)
       
       Layers of rocks are subjected to compressional forces.
       
       The parallel lines of weakness develop resulting to reverse faults.
                
       
       • Compressional forces may push the outer blocks towards each other, the outer ride over the middle block.
       • The sunken middle blocks forms a depression known as a rift valley.
    3. Explain five ways in which faulting is of significance to human activities. (10mks)
       • Faults leads to formation of features that form beautiful scenery which attract tourist.
       • Faults leads to formation of lakes that are important fishing grounds/tourist sites.
       • Faulting cover displacement of rocks which exposes minerals that are mined.
       • Block mountains formed through faulting lead to formation of relief rainfall on the wind ward side which favours agriculture/forestry/settlement.
       • Subsidence of land as a result of faulting may lead to loss of life and property.
       • Springs occurring at the fault scarps attract settlement.
       • Faults creates deep faults which are passage of steam jets which may be utilized for geothermal power production.
       • Faulting activity hinders transport and communication.