Ecological Relationships

Question 1

Gaia Hypothesis

Answer 1

• formulated by J.E. Lovelock
• named after the Greek goddess of Earth
• compares Earth to a living body
• emphasizes that all living things interact with each other and with the non-living components Earth

Question 2

Dynamic Equilibrium

Answer 2

• any system in which changes are continuous and componenets have the ability to adapt to changes without disturbing the entire system
• Earth’s dynamic equilibrium depends on the decisions of the human race

Question 3

Biosphere

Answer 3

• narrow zone around Earth that harbours life
• all life on Earth

Question 4

Levels of Organization

Answer 4

• groups of the same species (population) is influenced/influeces its immediate environment
• area with more than one population (community)
• functional unit of the biosphere (ecosystem) has both biotic and abiotic components

Question 5

Biodiversity

Answer 5

• number of species in an ecosystem
• a reduction in biodiversity can cause the collapse of a crucial part of the ecosystem

Question 6

Food Chain

Answer 6

• a step-by-step sequence linking organisms that feed on each other
• starts with a food source (autotrophs) and continuing with animals and other organisms that eat plants (heterotrophs) and on each other

Question 7

Predation

Answer 7

• when a species acts as a predator, it keeps the population of the prey in check
• when a species acts as a prey, it provides a food source

Question 8

Indicator Species

Answer 8

• a species sensitive to small changes in environmental conditions
• provides an early warning to negative changes to the ecosystem

Question 9

Ecology

Answer 9

• scientific study of the interactions of organisms and their environment
• involves observations and experiments to test hypothetical explanations of ecological phenomena

Question 10

Abiotic Factors

Answer 10

• space: access to food, water, shelter and mates
• tempurature: most organisms operate at a body tempurature of 0-45°C
• oxygen: required for cellular respiration
• sunlight: required for photosynthesis, affects develomental behaviour
• water: necessary for all life
• inorganic and organic soil nutrients: promotes the growth of producers and decomposers

Question 11

Biotic Factors

Answer 11

• detritus: decomposing plant and animal matter, decomposers provide nutrients
• disease: limiting factor on a community
• predation: limits the population of the prey
• competition: limits the size of competing organisms

Question 12

Sunlight

Answer 12

• 44% heats Earth’s atmosphere and surface
• 27% reflected by clouds
• 25% drives the water cycle
• 3% reflected off of Earth’s surface
• 1% generates wind
• <0.1% photosynthesis

Question 13

Photosynthesis

Answer 13

• uses the energy of sunlight to produce sugars
• oxygen is created as a byproduct and is released into the environment
• 6CO2+6H2O+sunlight→C6H12O6+6O2
• energy from the sun is tranfered into the sugar molecule