Chapters 3 & 4 Flashcards
Ecosystem
A biological community of interacting organisms and their physical environment.
Community
An interacting group of various species
Association
Relationships or interactions among living things
Population
All individuals of the same species living in the same area
How many species are there?
About 1.5 million. Estimated 100 million.
How many bacteria are there?
100 thousand.
How many protistans are there?
60-70k.
How many fungi are there?
100 thousand.
How many plantae are there?
300k.
How many animals are there?
6 million.
Trophic levels
Producers, primary consumers, secondary consumers, and tertiary consumers.
Natural selection
A process through which organisms adapt to their environment.
Factors behind species extinction
Habitat loss, an introduced species, pollution, and over consumption.
Earth’s mass extinction events (5)
Ordovician - Silurian, Devonian, Permian - Triassic, Triassic - Jurassic, Cretaceous - Tertiary.
Ecological organization
Population, community, ecosystem, biosphere.
Characteristics that help predict population growth
Size, density, age, birth rates, death rates, and sex ratio.
Explain how logistic growth, limiting factors, and carrying capacity affect population ecology
In logistic growth, population expansion decreases as resources become scarce. It levels off when the carrying capacity of the environment is reached.
Biosphere
Where land, water, and air interact with each other to support life.
Ecotone
Transitional region between different ecosystems.
Biotic factors
A living organism that shapes its environment.
Abiotic factors
A nonliving part of an ecosystem that shapes its environment
Habitat vs. niche
A habitat is a place. An animal’s ecological niche is what it eats, where it lives, and it’s predators.
Food chain
A hierarchical series of organisms each dependent on the next as a source of food
Food web
A system of interlocking food chains.
Autotroph
An organism like algae that makes its own food
Heterotroph
An organism like a lion that cannot make its own food.
Producers
Photosynthetic green plants.
Primary consumers
Herbivores, like rabbits that eat producers.
Secondary consumers
Carnivores, like bobcats that eat primary consumers.
Tertiary consumers
An animal like a big cat that eats primary and secondary consumers.
Predators
An organism that consumes part or whole of another living organism.
Decomposer/Detrivore
An organism like a worm, that breaks down waste and dead organisms.
Why isn’t the lion (carnivore) population as big ass the gazelle (grazer) population?
Competition from other animals.
How much energy is lost at each trophic level?
10%
Predator - prey relationships
One species is feeding on another species like lions and zebras.
Biotic factors in an ecosystem and their interactions
Biotic factors often change the geology and geography of an area.
Symbiosis
Interactions between individuals of two different species living closely together.
Mutualism
Both species benefit from their interactions like an oxpecker and a giraffe.
Commensalism
One species benefits and the other is unharmed like a remora and a shark.
Parasitism
One species benefits and the other is harmed.
Interspecific competition
Competition between two or more species.
Intraspecific competition
Competition between individuals of the same species.
Competition & niche overlap (aka competitive exclusion principal)
Two species can’t coexist if they occupy exactly the same niche.
Optimal foraging theory
Is a behavioral model that helps predict how an animal behaves when searching for food.
Resource partitioning
The division of limited resources by species to help avoid competition in an ecological niche.
Predation
The preying of one animal on another
Symbiotic relationships
Mutualism, commensalism, predation, parasitism, competition.
Pedogensis
Process of soil formation
Biological diversity
The variety of life in the world or a particular habitat
Invasive species
Any living organism that is not native and causes harm
Introduced species
A species that is not native and has been introduced by humans
Pioneer species
A species that is first to colonize a barren ecosystem
Keystone species
A species that an ecosystem largely depends on
Restoration ecology
Assisting the recovery of an ecosystem that has been damaged or destroyed
5 basic characteristics of living
Ability to obtain & utilize energy, reproduce, maintain homeostasis, and the basic unit is the cell.
3 domains (Average Ballerinas Exfoliated)
Archae, Bacteria, Eukarya
6 kingdoms (Plump Armadillos Fanned Pretentious Attractive Exorcists)
Plantae, Animalia, Fungi, Protista, Archaebacteria, and Eubacteria.
Humans: (7) Elephants Ate Chainsaws Meanwhile Philosophers Hollered Humanely
Eukarya, Animalia, Chordata, Mammalia, Primate, Hominidae, Homo.
Biome
A large, naturally occurring community of flora and fauna occupying a major habitat.
Climate
A general description of the average temperature and rainfall per year
Terrestrial biome
A biome that exists on land
What is production in an ecosystem?
The rate of generation of biomass
6 major terrestrial biomes
Deserts, grasslands & prairies, tropical rainforests, temperate forests, taiga/coniferous forests, and tundra.
Deserts
Shrubs, cacti, rodents, snakes. Very dry, less than 10 in. of rain per year. Soil is very thin.
Grasslands & prairies
Grass species, bushes, bison, coyotes. 10-60 in. of rain per year, rich soil.
Tropical rainforests
Evergreen trees, dense canopy, exotic insects, birds, tigers. Over 95 in. of rain per year. Soil is very thin.
Temperate forests
Deciduous trees, ferns, raccoons, black bears. 30-80 in. of rain per year, rich soil.
Taiga/Coniferous forests
Deciduous and coniferous trees, moose, bears, foxes. Less rain in winter, more in summer. Seasonal, and acidic soil.
Tundra
Dwarf shrubs, lichens, lynx, caribou. Very little rain, thin soil with permafrost underneath
Where is the world’s tallest tree?
A Redwood in Northern California
Human impacts on rainforests
Logging, cash crops, cattle ranching, fuelwood, and mining.
Aquatic biome
The largest of all biomes, divided into fresh water and marine.
Lakes & ponds
Plants, phytoplankton, turtles, ducks
Streams & Rivers
Algae, plants, fish, amphibians
Inland Wetlands
Grasses, trees, snakes, alligators. High in nutrients.
Estuaries
Mangrove trees, shrubs, phytoplankton, fish. Rich in nutrients.
Coastal Ocean
Phytoplankton, algae, shellfish, dolphins. High in nutrients.
Open Ocean
Phytoplankton, diverse fish, whales. 70% of earth surface. Mostly poor in nutrients.
Human impacts on coral reefs
Coral get sick and die in higher temperatures, over fishing, explosives & cyanide, pollution, global warming, 10% destroyed.
Which aquatic biome has the highest average annual net primary production?
Algae beds and coral reefs
Which terrestrial biome has the highest average annual net primary production?
Tropical rainforest.
Which aquatic and terrestrial biomes contribute most to the global net primary productivity?
Tropical rainforests, and open oceans.
The aquatic biome with a mixture of fresh and saltwater is called the marine system, true or false.
False
Freshwater ecosystems are characterized by low saltwater content, true or false
True
A tree that loses its leaves in the fall/winter is called
Deciduous
As one moves up the trophic energy pyramid the amount of energy available to the next trophic level decreases due to
The first law of thermodynamics
The 3 types of biodiversity are
Genetic, species, and ecosystem.
When important habitats are disconnected we refer to it as
Fragmentation
The current extinction rate is
Up to 1000 times higher than the fossil record.
An indirect cause of biodiversity is
Fires, hunting, ecotourism, climate change
True or false, the idea that one should not undertake a new action until the ramifications of that action are well understood is the conservation principle
False
True or false, a biodiversity hotspot has high biodiversity and is vulnerable to destruction
True
The survival and recovery of a population depends on a certain minimum population number
Critical number
One type of instrumental value is
All of these apply
Allopatric speciation
when species form from populations that become physically separated over some geographic distance
Endemic species
Specific to a particular region. Vulnerable to extinction because of events that might affect their region.
How are primary and secondary succession different?
Primary succession begins with no soil. Secondary soil begins when soil is already present.
How do competitors exist without replacing each other?
Each competitor has a niche. This is called niche differentiation.
What are the basic organism requirements of an ecosystem?
One producer, one decomposer, and water or air.
What form of life led to the existence of oxygen in Earth’s atomosphere?
Photosynthetic life, or plant life.
What is the difference between a positive feedback loop and a negative feedback loop?
Negative feedback loop is stabilizing.
Positive is destabilizing.
What is carrying capacity?
The maximum number of organisms an ecosystem can sustain.
3 outcomes once a population exceeds carrying capacity
Population stabilizes, export immigrants, or overshoot and crash.
