Biology Ecology (Alberta Topics)

Closed System

Allows for the exchange of energy not matter

Gaia Hypothesis

James E. Lovelock: Idea of earth being a living organism (mother earth)

Dynamic Equilibrium

Balanced state, system adjusts to change + undisturbed

Ex: The regulation of blood glucose levels in the human body

Biosphere and its 3 levels

Zone around earth that supports life

Lithosphere (Land)

Hydrosphere (water)

Atmosphere (air)

Biotic vs. Abiotic

Living vs non living

Biological levels of organization (order)

Cell, Tissue, Organ, Organ system, Organism, Population, Community, Ecosystem, Biome, Biosphere

Biological levels of organization (definitions) Cell

Smallest living part of an organism

Biological levels of organization (definitions) Tissue

Groups of cells with a similar function

Biological levels of organization (definitions) Organ

Group of tissues with a similar function

Biological levels of organization (definitions) Organ system

Groups of organs with a similar function

Biological levels of organization (definitions) Organism

Groups of organ systems that make up an organism

Biological levels of organization (definitions) Population

Groups of the same species in the same area

Biological levels of organization (definitions) Community

Different species in the same area

Biological levels of organization (definitions) Ecosystem

A community and its physical and chemical environment. Includes all organisms and abiotic factors that interact in an environment.

Biological levels of organization (definitions) Biome

Large area and its organisms

Biological levels of organization (definitions) Biosphere

Narrow zone around the earth that supports life

Biodiversity

Very beneficial. Different organisms in an ecosystem.

Food chain

Sequence linking organisms that eat each other. Extinction has a domino affect. Arrows=the flow of energy

Producer

Autotroph. Makes its own food.

Consumer

Heterotroph. Eats producers+other consumers to survive.

Indicator species

Sensitive to small environmental changes therefore giving us information

Ex: Bald eagle, Frogs

At risk species are classified by degree of risk. Endangered

Close to extinction in all parts of a country but can be found in other countries.

At risk species are classified by degree of risk. Extirpated

Species no longer exists in one part of a country

At risk species are classified by degree of risk. Threatened

Likely to become endangered if condition remain the same.

At risk species are classified by degree of risk. Special concern

Species at risk due to low or declining numbers at the fringe of its range or in a restricted area (which are the first places to lose population)

Members of food chains. Producer, Herbivore, Carnivore, Omnivores, Decomposers

Producer: Makes its own food/E (trophic level 1)

Herbivore: primary consumers (trophic level 2) And plant eating only

Carnivore: Secondary and higher level consumers, Meat eating

Omnivore: Eat both plant and animals

Decomposers: Deeds on detritus (waste from dead animals and plants)

What leads to species disappearing

Loss of habitat, Air and water quality, Climate change, Ultraviolet Radiation (UV)

“Biosphere 2”

An artificial biosphere created in Arizona, airtight greenhouse, acting as a prototype space colony in the 80s.

Did not end well.

The universe is made of matter and energy. What is matter? What is energy?

Matter: Anything that takes up space and has mass. Matter cycles.

Energy: The capacity to do work. Energy flows.

Trophic levels

(feeding levels in the food chain)

Producers (1)

Primary consumers (trophic level 2)

Secondary consumers (3)

Tertiary consumers (4)

Autotrophs (producers)

Access energy (E) from sunlight or non-organic sources sources

Converts inorganic —> organic (sunlight to sugar)

Makes up the basic trophic level 1 in an ecosystem that supports all other organisms

Photoautotroph vs Chemoautotroph

Photoautotroph: E from sun. Converted into chemical energy. All plants+Cyanobacteria

Chemoautotroph: Autotrophs that access E other than light, like from hydrothermal vents, sulfur, and some bacteria

Heterotroph

Consumers. Get energy from eating other animals/organisms

Primary consumers (trophic level 2)

herbivores

Secondary + Tertiary consumers

Carnivores (only eat animals)

Omnivores (eat producers and consumers)

Mixotroph

Unicellular organism that can swap between heterotroph and autotroph

Decomposers

Derive E from dead organisms and waste

Scavengers

Eat tissues from dead organisms

Detritovores

Eat detritus (decomposing things+feces)

Internal digestion

Mostly animals

Saprotrophs

Eat detritus like Detritovores but have external digestion

example: fungus

Food webs

Interconnected food chains within an organism. More stable as removing one organism has less of an effect. The Greater the biodiversity the better. Sometimes animals can be multiple roles in multiple trophic levels depending on what its eating. When an animal eats a secondary consumer it could be tertiary but it may also eat a primary consumer and be secondary in that case.

Laws of Thermodynamics

First Law of Thermodynamics

▪ Energy cannot be created nor destroyed, only changed from one form to another

Second Law of Thermodynamics

▪ With each successive energy transfer, less energy is available to do work

▪ In biological systems, this “waste” energy is often heat

Productivity is lower at…

higher trophic levels, there is less biomass (stored energy) at these levels.

High trophic levels have less biomass, large body size and therefore lower population densities.

1) Pyramid of Numbers

Displays number of organisms at each level. Bars=numbers relative to pyramid base. Pyramids are based on data from a given area. Ex: 1km2

2) Pyramid of Energy

E stored by each trophic level in calories or Jules. E per unit area per unit time. Kcal/m2/year.

shows energy per unit area per unit time, usually expressed as energy per square meter per year

3) Pyramid of biomass

Stored energy is represented by biomass (dry weight). Biomass per unit area per unit time

(g/m2/yr).

Inverted Pyramids

Higher trophic levels have more individuals or a greater total biomass than the lower producer level. The pyramid gets inverted because its just numbers.

Energy Loss in Pyramids

90 percent of energy is lost at each step of the pyramid making the 10 percent rule.

Feeding Humans

Could we feed larger populations of

humans if we ate only plants?

▪ Yes and no

▪ Yes

▪ Most energy in the ecosystem is

stored in producers

▪ No

▪ Humans cant access all the food

that cattle can

Monocultures

6-15 million different species

▪ Humans rely on 700 species, Mainly wheat, rice, cotton, barley corn

▪ Many wild plants destroyed to make food crops (lost potential)

▪ Negative consequences of Monocultures: Disease, Lack of biodiversity, Deplete soils of nitrogen and phosphorus

Pesticides

Cause a domino affect.

Benefits

▪ Reduce pests (weeds, mold, insects)

▪ Increase crop production

Negatives

▪ DDT can kill insects in a food chain, affect consumers (remember they made eagle eggs thinner)

▪ Many non-target species can be killed if not careful

Biological Amplification/Magnification

The build up of toxic chemicals in tissues of organisms as you move up the food chain

▪ DDT—>Falcons had thin shells, population dropped

Controlled vs. Manipulated vs. Responding Variables

Stays the same, what u change, what u measure