Introduction:
Understanding local biomes is essential for the WAEC Biology examination. This topic explores the various ecological regions found within Nigeria, their characteristics, and the adaptations of organisms within these environments.
Key Concepts:
1. Definition of Biomes:
Biomes are large ecological areas on the Earth’s surface, with flora and fauna adapting to their environment. In Nigeria, the primary biomes include:
- Tropical Rainforest: Characterized by high rainfall, dense vegetation, and rich biodiversity.
- Savannah: Marked by grasslands with scattered trees, experiencing distinct wet and dry seasons.
- Mangrove Swamps: Found along coastal regions, with salt-tolerant trees and unique root systems.
- Deserts: Arid regions with sparse vegetation, extreme temperatures, and specialized organisms.
2. Characteristics of Major Nigerian Biomes:
- Tropical Rainforest:
- High annual rainfall (over 2000 mm).
- Dense, multi-layered vegetation.
- High humidity and consistent temperatures.
- Savannah:
- Seasonal rainfall with a distinct dry season.
- Grass-dominated landscapes with scattered trees.
- Frequent fires that shape vegetation patterns.
- Mangrove Swamps:
- Located in coastal, saline environments.
- Vegetation includes trees with stilt and breathing roots.9as.ng
- Serve as important breeding grounds for aquatic species.
- Deserts:
- Low rainfall and high evaporation rates.
- Sparse vegetation with drought-resistant plants.
- Organisms adapted to extreme temperatures.
3. Adaptations of Organisms:
- Plants:
- In rainforests, plants have broad leaves for maximum photosynthesis.
- Savannah plants often have deep roots and thick bark to withstand fires.
- Mangrove trees possess specialized roots for stability and gas exchange.
- Desert plants, or xerophytes, have adaptations like thick cuticles and water storage tissues.
- Animals:
- Rainforest animals often exhibit arboreal lifestyles and camouflage.9as.ng
- Savannah fauna includes migratory herbivores and predators adapted to open spaces.
- Mangrove ecosystems support diverse aquatic and bird species.
- Desert animals are typically nocturnal and have water-conserving adaptations.
Sample WAEC Questions:
Objective Questions:
- Plants with breathing roots are characteristic features of vegetation in:
A. Tropical grassland
B. Temperate grassland
C. Saltwater swamp
D. Tropical rainforest
Answer: C - Most tropical plants shed their leaves during dry weather conditions to:
A. Reduce their growth rate
B. Conserve water
C. Reduce competition
D. Minimize the rate of photosynthesis
Answer: B - The rate of decomposition of organisms is faster in the tropical rainforest than in other biomes because:
A. Of the relatively constant daylight
B. There are more plants per square foot
C. Of abundance of water
D. Of constant cool temperature
Answer: C - The following habitats can be found in West Africa except:
A. Mangrove swamp
B. Sahel savannah
C. Savanna grassland
D. Temperate grassland
Answer: D - Which of these is NOT a true characteristic of the tropical rainforest?
A. Vegetation consists predominantly of tall trees with thick canopy
B. Forest is rich in epiphytes and climbers
C. Annual rainfall is less than 100 cm
D. Interior has low light intensity, high humidity, and damp floor
Answer: C
Theory Questions:
- Describe the characteristic features of the vegetation of the tropical rainforest.9as.ng
- List five morphological features characteristic of plants found in the tropical rainforest and state the function of each feature.9as.ng
- Give a brief description of the characteristics of the Northern Guinea Savannah.
- List four characteristics each of:
a. Trees of the tropical rainforest
b. Trees/shrubs of the savannah9as.ng - State five important uses of water to organisms in the tropical rainforest.9as.ng
- Name three plants and two animals found in savannah vegetation.9as.ng
- Name two local biotic communities in Nigeria and associate each type with a particular state in Nigeria.9as.ng
Study Tips:
- Understand Key Terms: Familiarize yourself with definitions and examples of different biomes and their characteristics.
- Use Diagrams: Visual representations can aid in understanding the structure and features of various biomes.
- Practice Past Questions: Regular practice with past WAEC questions enhances familiarity with exam patterns.
- Group Discussions: Engage in study groups to discuss and clarify complex topics.
- Consult Additional Resources: Utilize textbooks and reputable online platforms for comprehensive understanding.
Conclusion:
Check below for questions from this topic. Mastering the topic of local biomes is crucial for success in the WAEC Biology examination. A thorough understanding of the characteristics, adaptations, and significance of Nigeria’s diverse ecological regions will enhance your ability to answer related questions effectively.
OBJECTIVES
1. Plants with breathing roots are characteristic features of vegetation in
A. Tropical grassland. B. temperate grassland. C. salt water swamp. D. tropical rain forest.
2. Most tropical plants shed their leaves during dry weather conditions in order to
A. reduce their growth rate. B. conserve water. C. reduce competition. D. minimize the rate of photosynthesis.
3. The rate of decomposition of organisms is faster in the tropical rain forest than in other biomes because
A. of the relatively constant daylight. B. there are more plants per square feet. C. of abundance of water. D. of constant cool temperature.
4. The following habitats can be found in West Africa except
A. mangrove swamp. B. Sahel savanna. C. savanna grassland. D. temperate grassland
5. Which of these is NOT a true characteristic of the tropical rain forest?
A. Vegetation consists predominantly of tall trees, with thick canopy. B. Forest is rich in epiphysis and climbers. C. Annual rainfall is less than 100 cm. D. Interior has low light intensity, high humidity and damp floor.
6. The following are features of the tropical rain forest except
A. abundant water supply. B. loose and moist soil. C. short trees growing beneath tall trees. D. scanty trees with small leaves.
7. The following are features of Northern Guinea Savannah except
A. presence of tall trees with thick bark. B. bare soil with very few tree. C. presence of fire- resistant tree. D. D. abundant herbivores.
8. Trees in savannah habitats usually have heavy thick bark which mainly
A. reduces the rate of transpiration. B. protect them from the scorching sun. C. protect them from heavy winds. D. resist bush fires.
9. Which of the following is not a characteristic feature of tropical rainforest habitat?
A. Trees with longer boles than those in savannah. B. Fewer canopy strata than the savannah. C. Many more trees and climbers than savannah. D. Plenty of leaf litter on the ground.
10. Northern Guinea savannah is associated with
A. abundant rainfall. B. abundant trees and shrubs. C. soil with very little plant cover. D. abundant grasses.
11. How are Savannah plants protected from bush fires? They
A. have sunken stomata. B. roll their leaves during hot days. C. have thick barks. D. shed their leaves gradually throughout the year.
12. Very low annual rainfall, sparse vegetation, high day temperatures and cold nights are the characteristics of the biome known as
A. swamp. B. tropical forest. C. southern guinea savannah. D. desert.
13. Breathing roots are characteristic structures of plants growing in
A. mangrove swamp. B. desert. C. shrub biome. D. savannah.
14. The possession of breathing roots is a characteristic of plants growing in
A. mangrove swamp. B. coastal savannah. C. guinea savannah. D. shrub biome.
15. Fewer number of trees is characteristic of the Savannah zones of Nigeria because
A. here is too much sunlight. B. here is limited amount of rainfall. C. they are usually exposed to grazing animals. D. they are covered by high mountains.
16. Possession of strong adhesives is a feature of animals living in/on
A. sandy beaches. B. rocky shores. C. benthic zones. D. deserts.
17. A habitat with low rainfall, very low humility, exposed soil with little plant cover, few trees and shrubs is likely to be
A. a rain forest. B. a mangrove forest. C. a desert. D. a swamp.
18. Which of the following world biomes is found in Nigeria?
A. Sahel Savannah. B. Tundra. C. Desert. D. Afro-alpine vegetation.
19. The presence of stilt and breathing roots are features of plants found in the
A. tropical rain forests. B. fresh water swamp forest. C. mangrove forest. D. southern guinea savannah.
20. Which of the following is characteristics of a swamp?
A. Vegetation with stratified arrangement. B. Mesophytes with broad leaves. C. The ground is flooded most of the time. D. Predominance of climbing plants.
21. Desert plants are usually called
A. hydrophytes. B. mesophytes. C. xerophytes. D. sporophytes.
22. Which of the following factors is the main problem facing xerophytes?
A. Conservation of excess water. B. Competition for sunlight.C. Lack of adequate water. D. Poor formation of roots.
23. The rate of decomposition of dead organisms is faster in the tropical rainforest than in other bionics because
A. of consistent cool temperature. B. of the relatively constant daylight. C. there are more plants. D. of availability of moisture.
THEORY
1. (a) Describe the characteristic features of the vegetation of the tropical rain forest. (b) Name two types of savanna found in Nigeria giving one example in each case of a town where they occur.
2. List five morphological features that are characteristic of plants found in Tropical rainforest. State function of the features listed above to the plant.
3. Give a brief description of the characteristics of the Northern Guinean Savannah.
4. List four characteristics each of: (a) Trees of the Tropical Rain Forest (b) Trees/shrubs of the Savannah.
5. State five important uses of water to organisms the tropical rain forest.
6. Name three plants and two animals found in savannah vegetation.
7. Name two local biotic communities in Nigeria and associate each type with a particular state in Nigeria.
