Geography 2005 Jamb Examination

Temperate and sub-tropical grasslands occur mainly in southern Africa, where cooler and drier conditions support extensive grass-dominated biomes.
South Africa contains the Highveld and veld grasslands, while Lesotho, located at higher altitudes, also experiences temperate grassland vegetation.
Other listed pairs include countries with climates that do not support widespread temperate or sub-tropical grasslands.

The equatorial trough is the zone of intense heating and rising air around the equator, characterised by calm winds and frequent convectional rainfall.
This region is widely referred to as the doldrums because of its weak pressure gradients and minimal horizontal air movement.
The other terms refer to distinct global wind or pressure zones unrelated to the equatorial low.

Among the listed gases, carbon(IV) oxide is the most abundant greenhouse gas present in the atmosphere.
It is produced naturally through respiration, volcanic activity and decomposition, and in large quantities through human activities such as burning fossil fuels.
Although water vapour is the most abundant greenhouse gas overall, it is not included in the options, making carbon(IV) oxide the most significant among those listed.

Renewable resources are those that can be naturally replenished within a relatively short time through ecological processes.
Water, plants and soils fall into this category as they regenerate continuously through the hydrological cycle, biological growth and soil formation processes.
Minerals such as gold and iron ore take millions of years to form, making them non-renewable.

When vegetation develops over long periods without disturbance, it progresses through successive stages of ecological succession until it reaches a stable, enduring state.
This final stage is known as the climax community, where species composition and structure remain relatively constant under prevailing environmental conditions.
The other options describe different ecological concepts that do not represent the final equilibrium stage of vegetation.

Crystalline minerals are characterised by atoms arranged in a definite, orderly, and repeating geometric pattern.
This internal structure determines the mineral’s physical properties such as cleavage, hardness, and crystal shape.
Sedimentary rocks or vertical alignment do not define crystallinity.

Cool ocean currents typically stabilise air masses, reducing evaporation and moisture content.
If the winds are blowing offshore, they carry dry continental air towards the sea, resulting in cool and dry coastal conditions.
.Onshore winds, however, bring moist air inland, which contradicts the condition associated with cool currents.

Coniferous forests are dominated by conifers such as pine, spruce, and fir.
.They possess needle-like leaves adapted to withstand cold climates and reduce water loss.
.These trees also produce softwood, which is lighter and less dense than hardwood species.

The Earth rotates 360° in 24 hours, giving \( \dfrac{360}{24} = 15^{\circ} \) per hour.
This means each degree of longitude corresponds to \( \dfrac{60}{15} = 4 \) minutes of time difference.
.Therefore, two places differing by one degree of longitude differ by approximately four minutes.

Ecosystems maintain a natural balance through interactions among living and non-living components.
When one component is altered, the balance is disturbed, leading to disruption of ecological processes such as nutrient cycles and energy flow.
This disruption may trigger further adjustments throughout the system.