Chapter 1: Ecology and the Biosphere

Ecology

The study of our home (Earth) and the relationship between living and nonliving things in their environment

Biosphere

All areas that are inhabited by and support life

Atmosphere

Gaseous part of Earth (within 10km of Earth’s surface but extends higher)

Geosphere

Solid, mainly rocky part of Earth (aka Lithosphere)

Hydrosphere

All of the water (both liquid and solid) that exists and moves through the geosphere

Open System

A system that allows energy and matter to cross its boundary.

Closed System

A system that allows only energy (but not matter) to cross the boundary.

Law of Conservation of Energy

Energy cannot be created or destroyed, it can only change forms

Consumers (Heterotrophs)

Convert the stored energy in carbohydrates to power their cells via cellular respiration.

Albedo

The amount of light an object reflects

Greenhouse Gases

Gases that are very good at absorbing the infrared energy from the sun and keep the earth warm

Producers (aka Autotrophs)

Capture energy and store it by either photosynthesis or chemosynthesis.

Photosynthetic Producers

Convert carbon dioxide and light energy into stored energy in carbohydrates.

Chemosynthetic Producers

Convert energy from chemical bonds into stored biological energy.

Consumers (aka Heterotrophs)

Consume or eat organic matter made by producers or other organisms.

Primary Consumers (aka Herbivores)

First eaters of plants or other producers; Only eat plants, bacteria, algae, and any other organisms that are producers.

Secondary Consumers (Carnivores)

Animals that eat herbivores

Tertiary Consumers (Carnivores)

Animals that eat other carnivores or secondary consumers

Decomposers

Obtain energy by consuming dead organisms, shedded part of organisms, or waste materials (ex. feces)

Zeroth Law of Thermodynamics

Thermal equilibrium is transitive.

First Law of Thermodynamics

Energies are conserved, its form can be converted.

Second Law of Thermodynamics

Energies can flow, Equilibrate. energy conversion is not 100 % efficient

Third Law of Thermodynamics

The molecules within the steam move randomly. Therefore, it has high Entropy.

What are trophic levels?

Feeding levels within an ecosystem where energy is transferred from one level to the next, with most energy being lost during the transfer.

What are the three main ways an organism uses or releases it’s energy?

Waste energy (feces), incorporation into body tissues for growth and maintenance, and loss to the environment as heat.

What is a food chain?

A linear pathway showing the transfer of food from producers to primary consumers and then to higher trophic levels, typically limited to 3-6 levels due to the laws of thermodynamics.

How does a food web differ from a food chain?

A food web is a more complex and accurate model that illustrates the interconnectedness of species and tracks the transfer of food/energy more realistically in an ecosystem, enhancing survival.

What is bioaccumulation?

The accumulation of toxic chemicals in an organism's body as they consume food from the environment over time.

What is biomagnification?

The increasing concentration of toxic chemicals at higher trophic levels in an ecosystem.

What is the Rule of 10 in ecology?

On average, only about 10% of energy is transferred from one trophic level to the next, with the other 90% being lost, necessitating a constant energy supply to sustain life.

What do ecological pyramids represent?

Diagrams that illustrate the relative amounts of parameters such as organism number, biomass, or energy at each trophic level.

What does a pyramid of numbers show?

The relative number of organisms at each trophic level, although it can sometimes have strange shapes.

What is biomass, and what does a pyramid of biomass represent?

Biomass is the dry mass of living or once-living organisms per unit area, and a pyramid of biomass shows the relative amount of biomass at each trophic level.

What is unique about biomass in marine ecosystems?

Marine ecosystems may have more primary consumers (zooplankton) than producers (phytoplankton), despite the phytoplankton's rapid reproduction rate, due to them being consumed quickly.

Why is a pyramid of energy always pyramid-shaped?

A pyramid of energy must be pyramid-shaped because it shows the total amount of energy at each trophic level, with energy decreasing at higher levels due to the Rule of 10.

How does biodiversity affect ecosystem stability?

Biodiversity increases the stability of food webs and ecosystems, making them more resilient to changes.

How do changes in one trophic level affect other trophic levels?

Changes in one trophic level can affect all other trophic levels, as interconnected species rely on each other for food and energy.