Interactions with the Environment

Biotic Factors

Living components of an ecosystem (plants, animals, bacteria).

Abiotic Factors

Non-living physical and chemical components of an ecosystem (sunlight, temperature, water, soil).

• Predators (e.g., wolves)

• Prey (e.g., rabbits)

• Producers (e.g., plants, algae, some bacteria)

• Consumers (e.g., animals, humans)

• Decomposers (e.g., fungi)

examples of biotic factors

• Light intensity

• pH levels

• Water Availabilit

• Temperature

• Soil Composition

examples of abiotic factors

Light intensity

Abiotic factor that Influences photosynthesis rates in plants.

pH levels

Abiotic factor that Influence the chemical reactions in the soil and water, affecting plant and animal life.

Water Availability

Abiotic factor that Essential for all living organisms, influencing their distribution and behavior.

Temperature

Abiotic factor that Affects metabolic rates and enzyme activity in organisms.

Soil Composition

Abiotic factor that Affects plant growth and the types of organisms that can inhabit an area

Acidic

_____ soils can limit plant growth

Sandy

_____ soils drain quickly

neutral pH

_________ soils supports diverse plant life

clay

____ soils retain water.

abiotic

Organisms often adapt to their ______ environment

antifreeze proteins

fish in colder waters may have _____________ in their blood to prevent freezing

adaptations

Organisms have specific __________ that help them survive in their particular environments

Cacti

_____ in deserts have thick, fleshy stems that store water and spines that reduce water loss and deter herbivores.

Polar Bears

____________ have thick fur and a layer of fat to insulate against cold temperatures in Arctic regions.

depth

In aquatic environments, light availability decreases with _____, influencing the types of plants and animals found at different depths.

Ectotherms

cold-blooded animals

Endotherms

warm-blooded animals

reptiles

________ rely on external heat sources to regulate their body temperature. They bask in the sun to warm up and seek shade to cool down.

sphagnum moss

Acidic waters (low pH) in some bogs and swamps support specialized plant species like ___________, which can tolerate low pH levels.

stability

The balance between biotic and abiotic factors contributes to ecosystem’s _______

shifts

Changes in abiotic factors like climate change can disrupt this balance, leading to _____ in species composition and ecosystem function.

succession

Over time, ecosystems can undergo ___________, a process where the structure and composition of a community change due to biotic and abiotic factors. For example, after a forest fire (abiotic), pioneer species (biotic) like grasses and shrubs quickly colonize the area, followed by trees and larger plants as the ecosystem matures.

Ecosystem

A community of living organisms interacting with one another and their physical environment.

Community

Different populations of organisms living and interacting in a particular area.

Producers

Organisms that produce their own food (e.g., plants via photosynthesis)

Consumers

Organisms that eat other organisms

herbivores

Animals that eat plants

carnivores

Animals that eat other animals

Primary Consumers

Secondary Consumers

Tertiary Consumers

3 types of consumers

Decomposers

Organisms that break down dead material, returning nutrients to the soil. 

bacteria, fungi

example of decomposers

Food Chains

Linear sequences showing who eats whom.

Food Webs

Complex networks of interlinked food chains. They provide a more realistic representation of how organisms in an ecosystem interact.

biodiversity

High _________ increases ecosystem stability and resilience. It ensures that there are multiple species that can perform essential ecological functions.

Sunlight

Primary source of energy for most ecosystems

Photosynthesis

Process by which plants convert solar energy into chemical energy.

Equation: 

6CO₂ + 6H₂O + light energy → C₆H₁₂O₆ + 6O₂  

Trophic Levels

Levels in a food chain or food web.

10

Only about __% of energy is transferred from one trophic level to the next, with the rest lost as heat. This energy loss limits the number of trophic levels in an ecosystem

Pyramids of Biomass

Show the relative amount of living organic matter available at each trophic level. They typically have a broad base (producers) and a narrow top (top predators)

trophic levels

The efficiency of energy transfer affects the number of ______ ____ an ecosystem can support. They typically have a broad base (producers) and a narrow top (top predators).

• Photosynthesis

• Respiration

• Decomposition

• Combustion

Carbon Cycle Processes

Nitrogen Fixation

Conversion of atmospheric nitrogen into a usable form by bacteria.

Nitrification

Conversion of ammonia into nitrates

Assimilation

Plants absorb nitrates

Denitrification

Conversion of nitrates back into atmospheric nitrogen

Nutrient

_________ cycles ensure the availability of essential elements for life. They maintain ecosystem productivity and support life processes.

eutrophication

Excessive use of fertilizers can lead to nutrient runoff, causing ___________ in water bodies.

Carbon Cycle

What cycle?

A tree absorbs CO2 during photosynthesis. When the tree dies, decomposers break it down, releasing CO2 back into the atmosphere. If the tree is burned, CO2 is released rapidly.

Nitrogen Cycle

What cycle?

Legume plants have nitrogen-fixing bacteria in their root nodules. These bacteria convert atmospheric nitrogen into ammonia, which is then used by the plant.

Pollution

Sources: Industrial processes and waste disposal contribute to air, water, and soil pollution.

Air Pollution

Water Pollution

Soil Pollution

types of pollution

Air Pollution

Emission of harmful substances into the atmosphere (e.g., sulfur dioxide from industrial processes).

Water Pollution

Contamination of water bodies (e.g., oil spills, plastic waste).

Soil Pollution

Degradation of soil quality (e.g., heavy metals from industrial waste).

Health Problems

Ecosystem Damage

Climate Change

effects of pollution

Climate Change

Increased greenhouse gases from human activities lead to rising temperatures and changing weather patterns.

Conservation Strategies

______ ______ like protecting natural habitats and sustainable resource use aim to preserve biodiversity and ecosystem services.

Reforestation

Planting trees in deforested areas to restore ecosystems and sequester carbon.

Reforestation

Protected Areas

conservation examples

Great Pacific Garbage Patch

A massive collection of plastic waste in the Pacific Ocean, affecting marine life

Deforestation in the Amazon

Leading to habitat loss, reduction in biodiversity, and increased CO2 levels