Question 1
a. Explain the origin of the earth and the solar system according to the Nebula cloud theory.
b. Name two planets that do not have natural satellites.
Answer
- - There existed a big cloud (Nebula of hot gases and dust)
- This cloud which was rotating at a very high speed flattened into a disk due to centrifugal force.
- Very hot materials concentrated at the centre of the rotating cloud and led to the formation of the sun.
- Some masses of gases and dust were thrown off as the cloud continued to rotate.
- These materials cooled and condensed to form planets and other members of the solar system. - - Mercury
- Venus
Question 2
- Differentiate between physical and human environment.
- Give three sub branches of physical geography.
Answer
- Physical environment is made up of natural features while human environment is made up of features resulting from activities of people.
- - geomorphology
- climatology
- pedology
- oceanography
- bio-geography
Question 3
- Define earth movements
- State the boundaries associated with tectonic plates movements.
Answer
- Earth movement - These are the displacement of earth’s crustal rocks caused by tectonic forces
- - Extensional/divergence/constructive boundaries
- Compressional/convergence/destructive
- Transform/conservative
Question 4
Describe how an oasis is formed.
Answer
- A pre-existing depression is deepened by eddy action/ deflation.
- Gradually the depression is excavated through wind abrasions.
- The surface is lowered until it reaches the water bearing rock/ aquifer / water table.
- Water oozes out of the ground and collects in the depression to form an oasis.
- Gradually the depression is excavated through wind abrasions.
- The surface is lowered until it reaches the water bearing rock/ aquifer / water table.
- Water oozes out of the ground and collects in the depression to form an oasis.
Question 5
- Differentiate between secondary vegetation and planted vegetation.
- State three characteristics of Mediterranean vegetation.
Answer
- Secondary vegetation is the plants growing naturally in a place but has been interfered with by people while planted vegetation comprises plants which were grown in a place by people.
- - The vegetation is adopted to the long, hot and dry summers.
- Some plants are evergreen.
- Grasses dry up during summer and germinate during winter.
- Shrubs, thickets, bush and thorn bush and maquis are common.
- Woody scrub is common in very dry areas
- Some plants have small, springy leaves while others have thick-skinned leathering leaves.
- Some plants have deep roots.
- Some plants have thick barks.
- Some plants have large and fleshy bulbous roots.
- Some plants have fleshy leaves while other have skinny waxy leaves.
- Some trees are deciduous.