4-a The organism in the environment Flashcards
Q: What is an ecosystem, and what are its main components?
A: An ecosystem is a community of living organisms interacting with each other and their physical environment. The main components include:
Biotic factors:
Living components such as plants, animals, and microorganisms.
Abiotic factors:
Non-living components such as temperature, light, water, and soil.
Population
: A group of individuals of the same species living in the same area.
Community:
All the different populations living together in an ecosystem.
Habitat:
the specific environment where an organism lives.
What is the importance of biodiversity?
A: Biodiversity ensures ecosystem stability, resilience, and productivity. It supports food webs, nutrient cycles, and climate regulation.
How do abiotic factors affect the distribution of organisms?
Abiotic factors such as light, temperature, water availability, soil pH, and mineral content determine where organisms can survive and reproduce.
whats the role of Producers:
Green plants and algae that produce energy through photosynthesis.
whats the role of Consumers:
Animals that eat plants (primary consumers) or other animals (secondary and tertiary consumers).
whats the role of Decomposers:
Bacteria and fungi that break down dead organisms, recycling nutrients back into the ecosystem.
Food Chain:
A linear sequence showing energy transfer from one organism to another. Example: Grass → Rabbit → Fox.
Food Web:
A complex network of interconnected food chains that shows how energy flows through an ecosystem.
What is the pyramid of biomass, and what does it show?
A pyramid of biomass shows the total mass of living material at each trophic level. It is usually pyramid-shaped because biomass decreases as energy is lost between each level.
Practical: Investigating the Distribution of Organisms
Using Quadrats to Measure Plant Distribution:
Method: Place a quadrat randomly in an area, count the number of plants within the quadrat, and repeat multiple times. Calculate the average number per quadrat.
Positive Result: Higher numbers indicate greater plant abundance.
Negative Result: Low or zero numbers indicate sparse plant distribution.
Practical: Investigating the Distribution of Organisms
Using Transects to Measure Changes in Distribution:
Using Transects to Measure Changes in Distribution:
Method: Lay a tape measure (transect line) across a habitat and place quadrats at regular intervals. Record the number of species at each point.
Positive Result: More species indicate higher biodiversity.
Negative Result: Fewer species indicate low biodiversity.
What are some human impacts on ecosystems?A:
Human activities such as deforestation, pollution, habitat destruction, and climate change reduce biodiversity and disrupt ecosystems.
