GE ELECT 4 - Module 3 & 4

Question 1

• a founder of modern ecology and one of its most provocative thinkers and mobilizers in making environmentalism a people’s political
  cause.
• Responsible for the first celebration of Earth day in the world.
• His famous book, “The Closing Circle,” published in 1970, provides a clear and understandable example of what ecology truly means.
  Everything is connected to everything else

Answer 1

Barry Commoner

Question 2

Food Chain vs. Food Web

Answer 2

A food chain is a linear sequence of organisms where each is eaten by the next in line, showing who eats whom.

A food web is a more complex network of interconnected food chains in an ecosystem, showing how different organisms are related through multiple feeding relationships.

Question 3

takes place in a single organism over the span of its life, resulting in a higher concentration in older individuals

Answer 3

Bioaccumulation

Question 4

takes place as chemicals transfer
from lower trophic levels to higher trophic levels within a food web, resulting in a higher concentration in apex predators.

Answer 4

Biomagnification

Question 5

COMPETITION vs PREDATION

Answer 5

• competition arises when resources are in limited supply and organisms strive to obtain these resources.
• Predation often greatly reduces prey population density and alters community composition and species diversity.

Question 6

LAW OF THERMODYNAMICS

Answer 6

• First law of thermodynamics: Energy can neither be created nor be destroyed, it can only be transferred from one form to another.
• Second law of thermodynamics: The entropy of any isolated system always increases.

Question 7

• The mass in an isolated system can neither be created nor be destroyed but can be transformed from one form to another.

Answer 7

LAW OF CONSERVATION OF MASS (MATTER)

Question 8

• The main role of a _________________ is to recycle the elements on the earth. Biogeochemical cycle enables the transformation of matter from one form to another form. The byproducts of biogeochemical cycles assist the functioning of ecosystems.

Answer 8

biogeochemical cycle

Question 9

This is, of course, simply a somewhat
informal restatement of a basic law of
physics—that matter is indestructible.
Applied to ecology, the law emphasizes
that in nature there is no such thing as
“waste.” In every natural system, what is
excreted by one organism as waste is
taken up by another as food.

Answer 9

Everything must go somewhere

Question 10

The third law of ecology holds that
any major man-made change in a
natural system is likely to be
detrimental to that system.

Answer 10

Nature knows best

Question 11

is important for the growth and
development of an ecosystem. It initiates the colonization of new areas and the recolonization of the areas that had been destroyed due to certain biotic and
climatic factors.

Answer 11

Ecological succession

Question 12

Exploitation of nature, will always
carry an ecological cost and will
inevitably involve the conversion of
resources from useful to useless.

Answer 12

There is no such thing as a free lunch

Question 13

An ___________ consists of all the organisms living in a community, as well as the abiotic (non-living) factors with which they interact.

It can be visualized as a functional unit of nature, where living organisms interact among themselves and also with the surrounding physical environment.

It range from small, such as an aquarium, to large, such as a lake or forest.

Answer 13

ecosystem

Question 14

Energy for life begins with the _____

Answer 14

SUN

Question 15

is the ability to do work.

Answer 15

Energy

Question 16

is the amount of energy that moves through a food chain.
- aka Calorific flow

Answer 16

Energy flow

Question 17

AUTOTROPHS vs HETEROTROPHS

Answer 17

• Autotrophs build molecules themselves using photosynthesis or chemosynthesis as an energy source.
• Heterotrophs depend on the biosynthetic output of other organisms.

Question 18

FLOW OF ENERGY IN THE ECOSYSTEM

Answer 18

Energy and nutrients pass from primary producers (autotrophs) to primary consumers (herbivores) to secondary consumers (omnivores & carnivores) to tertiary consumers (carnivores that feed on other carnivores).

Question 19

are consumers that derive their energy from detritus.
- prokaryotes & fungi are important

Answer 19

Detritivores, or decomposers

Question 20

PRODUCERS

Answer 20

• can make glucose during photosynthesis.
• keep and use most of the energy they make for themselves.
• use cellular respiration to supply the energy for their life functions.

Question 21

is the process where sugar is converted into carbon dioxide, water, and energy.

Answer 21

Cellular respiration

Question 22

• The process where the Sun’s energy is converted into chemical energy (Glucose/Sugar).
• Occurs in PLANTS!
• On land, major producers are green plants that contain chlorophyll, which captures light energy.

Answer 22

PHOTOSYNTHESIS

Question 23

Carbon dioxide + water + light energy → sugar + oxygen

Answer 23

PHOTOSYNTHESIS

Question 24

are organisms that cannot make their own energy.

Answer 24

CONSUMERS

Question 25

TYPES OF CONSUMERS

Answer 25

• Herbivore: Eats plants or other producers.
• Carnivore: Eats other animals.
• Omnivore: Eats both plants and animals.
• Scavenger: Feeds on the remains of another organism.

Question 26

Are called first-orderor primary consumers.
Are herbivores (plant-eaters).
Use most of the energy they get from the producer

Answer 26

Consumers that eat producers to get energy:

Question 27

Are called secondary or second-order consumers.
May be carnivores or omnivores.
May be predators or scavengers.

Answer 27

Consumers that eat other consumers for energy:

Question 28

Are called third-order or tertiary consumers.
May be carnivores or omnivores.
May be predators or scavengers.

Answer 28

Consumers that eat a consumer that already ate a consumer:

Question 29

Are called omnivores.
Eat plants and animals.

Answer 29

Consumers that eat producers and other consumers:

Question 30

Energy moves from a starting point through living systems in a one-way direction

This movement is described as a flow of energy. The Sun is the major starting point for most living things on Earth.

Answer 30

FOOD CHAIN

Question 31

are models that demonstrate how matter and energy are transferred between producers, consumers, and decomposers as the three groups interact within the connected food chains in an ecosystem.

Answer 31

Food webs

Question 32

Energy transfer between trophic levels is typically only _________ efficient.

Answer 32

10%

Question 33

The atoms of earth and life are the same; they just find themselves in different places at different times.

________ occurs at the local level through the action of the biota.

occurs at the global level through geological processes, such as atmospheric circulation, erosion, and weathering.

Answer 33

Nutrient cycling

Question 34

The path atoms take from the living (biotic) to the non-living (abiotic) world and back again is called a

Answer 34

biogeochemical cycle.

Question 35

THE CARBON CYCLE

Answer 35

Plants Use Carbon Dioxide
* Plants pull carbon dioxide (CO2) from the atmosphere.
* Using sunlight with the CO2, they make glucose through photosynthesis.
* The carbon can be used by the plant for food and building materials (cellulose).
* Plants also release CO2 through cellular respiration.

When Animals Eat Plants
* When organisms eat plants, they take in the carbon, and it becomes part of their bodies.
* They generate CO2 through cellular respiration and exhale it into the atmosphere.

Animals Eat Animals
* When organisms eat animals, they take in the carbon, and it becomes part of their bodies.
* They generate CO2 through cellular respiration and exhale it into the atmosphere.

Plants and Animals Die
* When plants and animals die, most of their bodies are decomposed, and carbon atoms are returned to the atmosphere as CO2.
* Some remains are not fully decomposed and end up as underground deposits (oil, coal, etc. = fossil fuels = carbon).

Question 36

(N2) makes up 78% of the atmosphere.

Most living things cannot use atmospheric nitrogen to make amino acids and other nitrogen-containing compounds.

They depend on nitrogen-fixing bacteria to convert N2 into NH3 (NH4+).

Answer 36

Nitrogen

Question 37

THE NITROGEN CYCLE

Answer 37

Nitrogen Fixation: Atmospheric nitrogen (N2) is converted into usable ammonia (NH3).
Nitrification: Ammonia is converted into nitrate by bacteria in the soil.
Ammonification: Decomposers convert organic nitrogen into ammonia (NH3) and ammonium (NH4+).
Denitrification: Bacteria convert nitrites, nitrates, and nitrous oxides back into molecular nitrogen (N2).

Question 38

is important because it is how water reaches plants, animals, and us.

It also moves things like nutrients, pathogens, and sediment in and out of aquatic ecosystems.

Answer 38

water cycle

Question 39

THE WATER CYCLE

Answer 39

Evaporation: The sun heats water, turning it into vapor that enters the air.

Condensation: Water vapor cools and condenses into water droplets, forming clouds.

Precipitation: Water falls back to the ground as rain, snow, sleet, or hail.

Runoff: Rainwater flows downhill, attempting to return to oceans, lakes, rivers, or other water sources.

Question 40

is a biogeochemical process that involves the movement of phosphorus through the lithosphere, hydrosphere, and biosphere.

It is a very slow process, with weathering helping to wash phosphorus from rocks into the soil.

Answer 40

phosphorus cycle

Question 41

THE PHOSPHORUS CYCLE

Answer 41

Weathering: Weathering processes help to wash phosphorus from rocks into the soil.

Absorption by Plants: Plants absorb phosphorus from the soil.

Absorption by Animals: Animals obtain phosphorus by eating plants or other animals.

Return to the Environment through Decomposition: Decomposers break down dead organisms, returning phosphorus to the soil.