Components of an ecosystem and Ecological Factors for SS 1

Class: SS 1
Term: Second Term
Week: 4
Age: 15 years
Duration: 60 minutes
Subject: Biology
Curriculum Theme: Society and Environmental Biology
Focal competence: Measuring the effects of ecological factors on the environment
Key competencies/values: Collaboration; Environmental Literacy; Research and Problem Solving; Problem Solving
Skills:

• Observing components of the ecosystem to classify them as biotic and abiotic
• Measuring ecological factors in an environment

Previous Lesson: Ecological Concepts, Habitat, Niche, Population, Community and Ecosystem
Topic: Basic Ecological Concepts: Components Of An Ecosystem
Subject Matter: Components of an ecosystem, Ecological Factors

Specific Objectives

By the end of the lesson, pupils/students should be able to:

Cognitive Domain

• Define an ecosystem.
• Identify and classify biotic and abiotic components of an ecosystem.
• Explain various physical ecological factors.
• Describe different edaphic ecological factors.
• State examples of adaptations of organisms to their habitats.

Affective Domain

• Appreciate the interdependence of living and non-living components in an ecosystem.
• Demonstrate willingness to collaborate in group activities.

Psychomotor Domain

• Measure ecological factors in an ecosystem using appropriate instruments.
• Observe and differentiate between biotic and abiotic components in a given environment.

Social Domain

• Participate actively in group discussions and practical observations.

Reference Materials

The following resources were used in planning this lesson:

• 2025 New Revised Senior Secondary Education Curriculum (SSEC)
• Relevant State Unified Scheme of Work
• Modern Biology for Senior Secondary Schools by S.T. Ramalingam
• The HeadTeacher Scheme of work For The New Revised Senior Secondary Education Curriculum (SSEC)

Instructional Materials

The teacher will teach this lesson with the aid of:

• Chart on ecological concepts and components of an ecosystem
• Video clips and simulations on components of an ecosystem
• Measuring tape
• Rain gauge
• Hydrometer
• Thermometer
• Anemometer
• pH meter or litmus paper
• Soil samples

Rationale for the Lesson

Understanding the components of an ecosystem and the ecological factors that influence them is fundamental to appreciating how life thrives and interacts with its environment. This lesson provides students with the foundational knowledge to analyse environmental issues, understand biodiversity, and recognise the importance of ecological balance. It also equips them with practical skills to measure environmental parameters, fostering a scientific approach to environmental studies.

Prerequisite/Previous Knowledge

Students should have a basic understanding of living and non-living things, and simple environmental concepts from their Junior Secondary School science lessons.

Lesson Content/Board Summary

Basic Ecological Concepts: Components Of An Ecosystem

Meaning of Ecosystem

An ecosystem is a community of living organisms (biotic components) interacting with each other and with their non-living physical environment (abiotic components) in a specific area. It is a functional unit where energy flows and nutrients cycle.

Components of an Ecosystem

Ecosystems are made up of two main components:

1. Biotic Components (living things)
2. Abiotic Components (non-living things)

Biotic Components

These are all the living organisms within an ecosystem. They are classified based on their roles in the food chain:

1. Producers (Autotrophs): Organisms that produce their own food, mainly through photosynthesis (e.g., green plants, algae). They form the base of the food chain.
2. Consumers (Heterotrophs): Organisms that obtain energy by feeding on other organisms.
   1. Primary Consumers (Herbivores): Feed directly on producers (e.g., grasshoppers, rabbits, goats).
   2. Secondary Consumers (Carnivores/Omnivores): Feed on primary consumers (e.g., frogs, snakes, humans).
   3. Tertiary Consumers (Top Carnivores/Omnivores): Feed on secondary consumers (e.g., eagles, lions, humans).
3. Decomposers (Saprotrophs): Organisms that break down dead organic matter from producers and consumers, returning nutrients to the soil (e.g., bacteria, fungi).

Abiotic Components

These are the non-living physical and chemical factors that influence the organisms within an ecosystem. They include:

1. Physical Factors: Such as light, temperature, water, wind, humidity, atmospheric pressure.
2. Edaphic Factors: Related to the soil, such as soil pH, soil texture, soil water, soil air, mineral content.

Ecological Factors

Ecological factors are environmental conditions that influence the distribution, abundance, and interactions of organisms within an ecosystem. They can be broadly categorised into physical and edaphic factors.

Physical Factors

These are non-living environmental conditions that directly affect organisms:

1. Light: Essential for photosynthesis in plants. Affects animal behaviour (e.g., nocturnal vs. diurnal).
2. Temperature: Influences metabolic rates, growth, and reproduction of organisms. Organisms have optimal temperature ranges.
3. Water: Crucial for all life processes. Availability (rainfall, humidity) and form (liquid, ice) greatly impact ecosystems.
4. Wind: Affects plant transpiration, seed dispersal, and can cause physical damage. Influences temperature and humidity.
5. Humidity: The amount of water vapour in the atmosphere. Affects transpiration rates in plants and water loss in animals.
6. Atmospheric Pressure: Changes with altitude and can affect physiological processes, especially in aquatic and high-altitude environments.

Edaphic Factors

These are factors related to the soil that influence plant growth and the organisms living within the soil:

1. Soil pH: The acidity or alkalinity of the soil. Affects nutrient availability and microbial activity.
2. Soil Texture: The proportion of sand, silt, and clay particles. Influences water retention, aeration, and nutrient holding capacity.
3. Soil Water: Water held within the soil, essential for plant uptake and soil organisms.
4. Soil Air: Air spaces within the soil, necessary for root respiration and aerobic soil organisms.
5. Mineral Content: The presence and availability of essential nutrients (e.g., nitrogen, phosphorus, potassium) for plant growth.
6. Soil Organisms: Microbes (bacteria, fungi) and invertebrates (earthworms, insects) that contribute to soil fertility and decomposition.

Adaptations of Organisms to their Habitat

Adaptation refers to a feature or characteristic of an organism that helps it to survive and reproduce in its specific environment. Organisms develop various adaptations to cope with different ecological factors.

1. Adaptations to Water Availability:
   • Xerophytes (e.g., cacti, desert plants): Have thick waxy cuticles, sunken stomata, reduced leaves (spines), deep roots, or succulent stems to conserve water in dry environments.
   • Hydrophytes (e.g., water lilies, duckweed): Have large flat leaves to float, stomata on upper surface, air sacs for buoyancy, and reduced root systems in aquatic environments.
   • Mesophytes (e.g., most terrestrial plants): Have moderate adaptations to water, thriving in environments with adequate water.
2. Adaptations to Temperature:
   • Animals in cold climates (e.g., polar bears, seals): Have thick fur, blubber (fat insulation), hibernation, or migration.
   • Animals in hot climates (e.g., camels, desert foxes): Have light-coloured fur, large ears for heat dissipation, nocturnal activity, or aestivation.
   • Plants: Some plants have mechanisms to tolerate frost or heat stress.
3. Adaptations to Light Intensity:
   • Shade-loving plants (Sciophytes): Have broad, thin leaves with more chlorophyll to capture scarce light.
   • Sun-loving plants (Heliophytes): Have smaller, thicker leaves, often with protective pigments against intense light.
4. Adaptations to Soil Type:
   • Mangroves: Have prop roots and pneumatophores (breathing roots) to anchor in unstable, waterlogged, and saline soils.
   • Plants in nutrient-poor soils: May develop symbiotic relationships with nitrogen-fixing bacteria or become carnivorous (e.g., pitcher plants).

Teaching Methods/Instructional Techniques

Discussion, Explanation, Observation, Group Work, Demonstration, Question and Answer, Practical Activity.

Instructional Procedures

Step 1: Introduction

Time: 5 minutes

Teaching Skill: Questioning/Engaging

Teacher’s Activity: The teacher asks students to name some living and non-living things they see around their school compound and how they interact. The teacher then introduces the concept of an ecosystem as the interaction between these components.

Pupils’ Activity: Pupils mention various living and non-living things and discuss their interactions.

Learning Point: Ecosystem introduction

Step 2: Biotic Components of an Ecosystem

Time: 10 minutes

Teaching Skill: Explanation/Video Analysis

Teacher’s Activity: The teacher guides students in smaller groups to watch video clips showing different living organisms in an environment. The teacher then explains and discusses the biotic components (producers, consumers, decomposers) with examples, relating them to the video clips.

Pupils’ Activity: Pupils watch video clips, identify living organisms, and discuss their roles in groups. They listen and contribute to the explanation of biotic components.

Learning Point: Biotic components identification

Step 3: Abiotic Components and Ecological Factors (Physical)

Time: 10 minutes

Teaching Skill: Explanation/Observation

Teacher’s Activity: The teacher continues guiding students to observe non-living elements in the video clips or in their immediate environment. The teacher then explains abiotic components and focuses on physical ecological factors (light, temperature, water, wind, humidity, atmospheric pressure), highlighting their importance.

Pupils’ Activity: Pupils observe non-living elements, identify physical factors, and ask questions for clarification.

Learning Point: Physical ecological factors

Step 4: Ecological Factors (Edaphic)

Time: 8 minutes

Teaching Skill: Explanation/Demonstration

Teacher’s Activity: The teacher explains edaphic factors (soil pH, soil texture, soil water, soil air, mineral content) using soil samples. The teacher may demonstrate how to test soil pH using litmus paper or a pH meter.

Pupils’ Activity: Pupils observe the soil samples, participate in the pH test demonstration, and discuss the importance of each edaphic factor.

Learning Point: Edaphic ecological factors

Step 5: Measuring Ecological Factors

Time: 10 minutes

Teaching Skill: Demonstration/Guided Practice

Teacher’s Activity: The teacher demonstrates how to use instruments like a thermometer (for temperature), rain gauge (for rainfall), hydrometer (for humidity), and measuring tape (for area/distance) to measure ecological factors. The teacher then guides students to practice measuring these factors in a designated area within the school compound.

Pupils’ Activity: Pupils observe the demonstrations, practice using the instruments, and record their measurements.

Learning Point: Measuring ecological factors

Step 6: Adaptations of Organisms to their Habitat

Time: 7 minutes

Teaching Skill: Explanation/Examples

Teacher’s Activity: The teacher explains the concept of adaptation and provides various examples of how organisms (plants and animals) adapt to specific physical and edaphic factors in their habitats (e.g., desert plants for water conservation, polar animals for cold, aquatic plants for waterlogged conditions).

Pupils’ Activity: Pupils listen to the explanations, ask questions, and contribute additional examples of adaptations they know.

Learning Point: Organism adaptations

Step 7: Evaluation/Review

Time: 5 minutes

Teaching Skill: Questioning/Assessment

Teacher’s Activity: The teacher evaluates the learning by asking the following questions:

1. What is an ecosystem?
2. Differentiate between biotic and abiotic components of an ecosystem.
3. List three physical ecological factors and two edaphic ecological factors.
4. Mention one instrument used to measure temperature and another for rainfall.
5. Give an example of an adaptation of a desert plant to its environment.

Pupils’ Activity: Pupils answer orally and in writing.

Learning Point: Ecological concepts assessed

Step 8: Note-Taking

Time: 10 minutes

Teaching Skill: Guided Writing

Teacher’s Activity: The teacher guides pupils/students to copy the essential Board Summary notes on the components of an ecosystem, ecological factors, and adaptations into their notebooks.

Pupils’ Activity: Pupils/students copy the notes carefully into their notebooks.

Learning Point: Notes copying

Step 9: Conclusion

Time: 5 minutes

Teaching Skill: Consolidation

Teacher’s Activity: The teacher summarises the key points of the lesson, reiterating the interconnectedness of living organisms and their environment, and encourages students to observe their surroundings with an ecological perspective.

Pupils’ Activity: Pupils listen attentively and ask any final questions.

Learning Point: Lesson consolidation

Continuous Assessment/Further Study

Type: Homework/Practical Exercise

Instruction: Answer the following questions and carry out the practical task:

1. Define the following terms: (a) Ecosystem (b) Biotic factors (c) Abiotic factors.
2. List five physical ecological factors and three edaphic ecological factors.
3. Describe one adaptation of an aquatic plant and one of a terrestrial animal to their respective habitats.
4. Practical Task: In your home environment, identify three biotic components and three abiotic components. Observe and record the temperature and humidity for a day (morning, afternoon, evening) using any available means (e.g., weather app for temperature, general observation for humidity).

Lesson Keywords

• Ecosystem – A community of living organisms interacting with their non-living environment.
• Biotic Components – Living parts of an ecosystem (e.g., plants, animals, microbes).
• Abiotic Components – Non-living physical and chemical parts of an ecosystem (e.g., light, water, soil).
• Ecological Factors – Environmental conditions influencing organisms.
• Physical Factors – Non-living environmental conditions like light, temperature, water.
• Edaphic Factors – Soil-related factors like soil pH, texture, water content.
• Adaptation – A characteristic that helps an organism survive in its environment.
• Producers – Organisms that make their own food.
• Consumers – Organisms that feed on other organisms.
• Decomposers – Organisms that break down dead organic matter.

Differentiation

Support: For students who struggle, provide simplified charts of ecosystem components and ecological factors. Pair them with more capable students during group activities and measurement tasks. Offer sentence starters for definitions and explanations.
Extension: Encourage advanced students to research specific Nigerian ecosystems (e.g., mangrove swamps, rainforests, savannas) and identify the unique biotic, abiotic factors, and adaptations found there. They can also explore the impact of human activities on these ecological factors.

Suggested Lesson Videos

Search on YouTube for: components of ecosystem biology ss1 nigeria