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GEOGRAPHY
MARKING SCHEME
SECTION A
1. 1. (a) Name the (i) planet nearest to the sun (1 mk)
Mercury
(ii) Furthest from the sun (1 mk)
Pluto
(b) State three effects of the rotation of the earth (3 mks)
 Day and night
 Rise and fall of tides
 Deflection of winds and currents
 Difference of one hour between meridians 150 apart Any 3×1=3 mks
2. (a) Plate tectonic theory states that the continental crust is made of blocks called plates which
are mobile and move either; away from each other, towards each other or past each other
2 x 1 = 2mk
(b) Features formed when tectonic plates
(i) Move towards each other
- Fold mountains
- Formation of trenches
- Destruction of plates along their margins
2 x 1 = 2mks
(ii) Move away from each other
- Faults
- Extension boundary forming
- Mid-ocean ridges 2 x 1 = 2mks
3. (a) Name the three main layers of the atmosphere from the earth’s surface upwards

Troposphere Stratosphere Mesosphere

Accept in this order (3 x 1 = 3mks)
(b) What is temperature inversion?
A condition in the atmosphere where upper layer of air is warmer than the lower layer. (2mks)

4. (a) Two crater lakes in E. Africa (i) Pare (ii) Simbi 2 x 1 = ( 2 marks )
(b) Economic uses of lakes
(i) Fishing (iv) Tourist attraction
(ii) Industrial use (v) Domestic use
(iii) Irrigation Any 3 x 1 = ( 3 marks )
5. Name the parts marked E, F, G, H. (4 marks)

 E Blow hole.
 F Headland.
 G Cliff
 H Bay 4 x 1 = 4 marks.
 SECTION B

6. (a) (i) Give longitudinal extent of area covered by the map. (2mks)
- 35º 00’ E to 35º 15’ E

(ii) Identify the settlement patterns found on the Northern area covered by the map (3mks)
- Nucleated.
- Linear.
- Scattered. Max 3mks

(b) (i) Measure the distance of the Kitale municipality boundary.

Give your answer in kilometres. (2mks)
8.2 km + 0.1 km
(ii) What is the bearing of the air photo principal point on the grid square 2912 from
the air photo principal point on grid square 3516. (2mks)
- 223º + 1º.

(iii) Calculate the area to the east of the district boundary and to the South of
Northing 23. (2mks)
Full squares - 4
12
−6
Half squares - 2
10km² (2mks)

2
(d) (i) Identify two types of vegetation found in the area covered by the map. (2mks)
- Forest.
- Woodland
 - Scrub
- Papyrus swamp.
- Tree swamp
- Riverine trees. max 5mks
(ii) Describe the drainage of the area covered by the map. (5mks)
- There are Swamp.
- There are seasonal swamps.
- There are permanent rivers.
- There are many permanent rivers.
- Short rivers.
- The main rivers are Kapolet and Noigameget.
- Dams present. Max 5 = 1 x 5 = 5mks

7. (a) – Tilt block

- Escarpment/scarp slope
- Block mountains/Horsts
(2 x 1 = 2mks)

(ii) Formation of the rift valley through tension forces

- Layers of crustal rocks are subjected to tensional forces
- This causes instability within the earth’s crust

- Parallelnormal faults develop/lines of weakness develop

3
This results to sinking of the middle block which forms a depression known as the rift valley
 (b) Explain four effects of faulting
(Points should be well explained to score the marks)
- Faulting/fault scarps make it difficult to construct roads/railways
- Depression in the rift valley contain water that forms lakes
- faulting exposes minerals such as diatomite
- The scarp slopes tend to discourage settlement
- Some rivers such as Katonga in Uganda have had their direction of flow changed
Any 4 explained 4 x 2 = 8mks

(c) (i) Previsit

- Enables them to draw up study objectives / hypthesis
- To familiarize themselves with the area of study
- To enable them draw a route-map
- Enables them to prepare a work schedule/plan of activities
- Enables them identify/sort out relevant tools/equipment for the study
- Enables them to identify suitable methods of data collection
- Enables them to prepare financially
(1 x 4 = 4mks)

(ii) Disadvantages
- It is expensive
- Time consuming
- It is tiresome
- Limited only to direct sources/primary sources
- Only suitable to the sighted people

8. (a) What is a glacier? (2 marks)

- Glacier is a mass of ice having limited width and moving outwards from the
point of accumulation.

(b) Describe how the following glacial erosional processes occur.

(i) Plucking (3 marks)
- Occurs in well-jointed rocks such that the melt water will enter into
the rock cracks.
- Temperature slightly reduces/falls and the melt water freezes in the rock cracks.
Repeated action of freezing and thawing enlarges the rock cracks and eventually
causing and eventually causing part of the rock to fall off, pulled and carried
away by the moving glacier.
 (ii) Abrasion (3 marks)
- Occurs when the rock debris at the base and sides of the glacier is
used as a tool for scratching and polishing the rock surface over
which the glacier moves.
- The underlying rocks will be smoothened when the debris are
dragged along the rocks as the glacier moves.

(c) (i) Name the features marked W, X, Y and Z. (4 marks)

W - Esker
X - Boulder clay plain/till plain
Y - Outwash plain
Z - terminal moraine

(ii) Describe how a drumlin is formed. (5 marks)

- They are formed when deposition of glacial materials/ clay on the
plains/ boulder clay plains beneath ice due to friction between the
bed rock and the boulder clay plain.
- Continual deposition leads to formation of large mould of the
deposits irregularly as long egg-shaped hills whose upstream side
being steep and smoothened and gentle downstream features called
drumlins.

(d) Explain four negative effects of glaciations in low-land areas. (8 marks)

- Outwash plains may have infertile sand deposits making such area unsuitable for
agriculture.
- Deposits of moraine results in the formation of numerous Moraine - dammed lakes
reducing land for settlement and agriculture.
- Boulder clay plains may create marshy conditions having poor drainage discourage
human settlement and agriculture.
- Presence of erratic, drumlins and kettle lakes makes the landscape rugged discouraging
construction of transport and communication lines.
- Some minerals may be buried deep underneath the moraine making it difficult /expensive
to mine.

9. a) (i) Define natural vegetation

Natural vegetation is a plant cover that grows and spreads through natural means of seed
dispersal without interference of external modifying influence (1x1=1mk)
(ii) State four characteristics of natural vegetation found in tropical rain forests.
-Forest consists of mixed variety of the species
-Trees are evergreen
-Trees are tall
-Trees have large trunks
-Trees have broad leaves.
-Trees take long-time to mature
-Trees are hardwoods
-Trees are close to each other
-Forests have little/no undergrowth
-Trees have buttress roots
-Forests have three distinct layers/canopies
 -They have ephiphytes-climbing plants
-Straight with smooth trunks
-Have some low growing plants-saprophytes (4x1=4mks)
(b) Four ways in which vegetation found in arid areas adapts to the environmental conditions.
-Some plants have thick (fleshy) succulent leaves to store water
-Some plants have long roots to tap water from underground water
-Some plants have spuky /thin/waxy needle like leaves to reduce rate of transpiration
-Plants seeds remain dormant awaiting the short rains/short-lived plants
-Some plants have thick /hard barks to reduce transpiration/protection against sand blasts.
-Some plants are stunted due to harsh conditions
-Some plants are quick in sprouting to take advantage of little rainfall
-Dense cell fluids,complex sunken stomata
-Salt-tolerant (halophytes)
-Deciduous (3x1=3mks)

(c) Names of the grasslands in the following areas.

(i) East Africa-Savanna
(ii) Canada-prairies
(iii) Argentina-Pampas (3x1=3mks)

(d) (i) Give Reasons why Tundra region has scanty vegetation.
The ground is frozen most of the year
-Area has very short growing season/short summer
-The area has thin soils
-Some parts are poorly drained/bog-wet,spongy ground
-Area has low precipitation
-Very strong winds which intefere with seed dispersal (2x1=2mks)
(ii) Two topographical factors that influence vegetation distribution.
-Relief
-Drainage
-Aspect (2x1=2mks)
(e) Five economic importance of vegetation. --
Medicinal value
-For aesthetic value/beauty
-Habitat for wild animals
-Sources of building /construction materials e.g timber
-Source of fodder/feeding of animals/food for man
-Control of soil erosion
-Influence of rainfall formation
-Source of raw materials for industries e.g pulp and paper industries
-Forests protect water catchments areas

10.
(ii) Description of rainfall patterns of the station
- There is rain throughout the year/no dry month
- The highest rainfall is received during the hot months from January to March / October to December
- The lowest rainfall occurs during the coolest months May to September
- The driest month is July with 27mm
- The wettest month is March with 129mm
- Total annual rainfall is 1103 mm moderate rainfall
- The station experiences one long wet season / one short dry season
4mks
(ii) Average monthly temperature
239 = 19.910c
12 1mk

(b) (i) Latitude

- Areas near the Equator are hotter than those far away from the Equartor. This is due to a higher
concentration of the sun’s rays per unit area at the Equator/the amount of solar radiation decreases
polewards since it passes through a longer distance of atmosphere leading to low temperature at the
poles
- Also the sun rays strikes the earth surface at a right angle 900 at the Equator leading to intense heating /
the angle of the sun rays is lower / acute at the poles leading to less intense heating (2mks)

(ii) Aspect
- In Northern hemisphere outside the tropics the north facing slopes are colder than the south facing
slopes because they don’t receive direct solar radiation
- The reverse is true of the Southern hemisphere
- Windward slopes of high mountains/hills are generally wetter than leeward slopes because the
moisture laden winds rise and drop their moisture on this side first

(iii) Ocean currents

- Where winds are onshore, warm ocean currents have a warming effect on the adjacent coast – lead to
higher rainfall than inland areas
- Cold ocean currents have a cooling/drying effect on the adjacent lands (2mks)

(c) Effects of climate change on the physical environment

- Global warming/increased temperature may lead to increased evaporation of ocean water which may
cause heavy rainfall in some areas.
- Increased temperature may lead to melting of ice caps/ice sheets and glaciers leading to rising sea level
- Increased temperature may lead to high evaporation causing drought
- Climate change may cause changes in rainfall patterns in different parts of the world

(d) Problems associated with convectional rainfall in the Lake region of Kenya
- Torrential/heavy rains cause floods which displace people
- The hailstones which sometimes accompany convectional rainfall destroy crops
- The strong winds associated with convectional rainfall blow off roofs of houses and uproot trees and
crops
- Lightning strikes cause deaths of people and animals
2 x 2 = 4mks