Bio 101 Flashcards
What is ecology?
A branch of biological science focused on the relationships between organisms and their environment
Ecology became prominent in the second half of the 20th century.
Who is considered one of the first ecologists?
Aristotle or Theophrastus
Theophrastus described interrelationships between animals and their environment in the 4th century BC.
What concept did Carl Linnaeus contribute to ecology?
The economy of nature
Linnaeus was an influential naturalist who laid groundwork for ecological studies.
What did Alexander von Humboldt describe?
The ecological gradient of latitudinal biodiversity increase toward the tropics
His work in 1807 significantly advanced ecological understanding.
What is biocoenosis?
The concept of an ecological community
Developed by Karl Möbius, it refers to living communities.
Who coined the term ‘ecology’?
Ernst Haeckel
He popularized the links between ecology and evolution.
What is the Gaia hypothesis?
The view of Earth as a macro-organism
Advanced by James Lovelock, it recognizes the interconnectedness of life and the environment.
What is human ecology?
The study of humans as an ecological factor
It began in the early 20th century, emphasizing human impacts on the environment.
When did human ecology become a distinct field of study?
In the 1970s
This marked the recognition of humans as significant ecological factors.
What role did Theodore Roosevelt play in conservation?
He established national parks, monuments, and forests
Roosevelt protected over 200 million acres of land during his presidency.
What is the significance of the 1972 United Nations conference in Stockholm?
It marked the beginning of global ecological policy
The phrase ‘Think Globally, Act Locally’ originated from this event.
Define autecology.
The study of ecology at the level of species
It focuses on individual life forms and their interactions with the environment.
Define synecology.
The study of ecology at the level of communities
It examines the development, distribution, and structure of ecological communities.
What is the ecological hierarchy?
Organism → Species → Biotic community → Ecosystem → Biome → Biosphere
This hierarchy illustrates the organization of ecological study.
What distinguishes a keystone species?
A predator species that significantly influences community characteristics
Example: lions in forests.
What is a critical link species?
Species that assist others in vital activities
Examples include pollinators for plants.
What is a biome?
A large geographical area consisting of communities
Biomes reflect specific climates and ecosystems.
What does the biosphere refer to?
The global sum of all ecosystems
It represents the zone of life on Earth.
What are the eight features of a living thing?
- Made of cells
- Can reproduce
- Contains DNA
- Grows and develops
- Uses energy
- Maintains internal environment
- Involved in evolution
- Can respond to environment
These features define what constitutes a living organism.
What is the focus of molecular ecology?
The study of environmental effects on protein generation
It examines how proteins influence life forms at the molecular level.
True or False: Ecology is solely the study of living organisms.
False
Ecology also involves abiotic factors and their interactions with biotic components.
What is a community in ecological terms?
All the populations of different species that inhabit a particular area and interact with each other.
Define ecosystem.
A biological community of organisms and their physical environment.
What components constitute an ecosystem?
Biotic components and abiotic components.
What is a biome?
Consists of communities present in a large geographical area.
Define biosphere.
The global sum of all ecosystems, the zone of life on Earth.
What is a habitat?
A natural environment of an organism where it grows, lives and reproduces.
What are critical link species?
Species that help other species in vital activities, such as pollinators.
Fill in the blank: An ecosystem is a system consisting of biotic and abiotic components that function together as a _______.
[unit]
What are biotic components?
All living components in an ecosystem.
List the types of consumers in an ecosystem.
- Primary consumers (herbivores)
- Secondary consumers (carnivores or omnivores)
- Tertiary consumers (carnivores or omnivores)
What role do decomposers play in an ecosystem?
They recycle nutrients by thriving on dead and decaying organic matter.
Define abiotic components.
The non-living components of an ecosystem.
List some abiotic factors.
- Air
- Water
- Soil
- Minerals
- Sunlight
- Temperature
- Nutrients
- Wind
- Altitude
- Turbidity
What are edaphic factors?
Factors that relate to the structure and composition of the soil.
Define soil texture.
The relative proportion of various particles of the soil.
What is a soil profile?
The vertical section of the soil showing a series of horizontal layers called horizons.
What determines the suitability of soil for agriculture?
The soil profile.
What is soil air?
The air that fills the soil pore spaces not occupied by water.
What are the three types of soil water?
- Hygroscopic water
- Gravitational water
- Capillary water
Define soil pH.
The measure of the degree of acidity or alkalinity of the soil.
What is the primary source of energy for almost all ecosystems?
Light.
How does temperature affect ecosystems?
It influences the metabolic rate of organisms and their development.
What is the role of water in ecosystems?
Essential for life processes, including germination, digestion, and nutrient absorption.
What are hydrophytes?
Plants adapted to live in aquatic environments.
Define mesophytes.
Plants that can survive in moderate environments.
What are xerophytes?
Plants adapted to survive in physiologically dry conditions.
What is a microhabitat?
A tiny area that differs from the surrounding environment.
List some types of terrestrial habitats.
- Forest habitat
- Grassland habitat
- Tundra habitat
- Desert habitat
- Taiga habitat
What characterizes tundra habitats?
Treeless areas with cold temperatures and short summers.
Define taiga.
A region characterized by evergreen coniferous forests, located just south of the tundra.
What are grasslands?
Ecosystems covered with heavy growth of grass, found in temperate and tropical regions.
What defines desert habitats?
The driest places on Earth with less than 10 inches of rain per year.
What are the main types of aquatic habitats?
- Marine
- Estuarine
- Freshwater
What is the epipelagic zone?
The upper part of the ocean where enough sunlight allows for photosynthesis.
What is the mesopelagic zone also known as?
The middle part of the ocean or the twilight zone.
Define bathypelagic zone.
The lower open ocean, beginning at the bottom of the mesopelagic area.
What is the elagic zone also known as?
The middle part of the ocean or the twilight zone
What depth does the elagic zone extend to?
Around 3000 ft or 1000 m deep
What is the primary characteristic of the bathypelagic zone?
It has no sunlight and is the largest ecosystem on our planet
What types of animals commonly inhabit the bathypelagic zone?
- Anglerfishes
- Bristle mouths
What is the abyssal zone known for?
Having almost no life
List some examples of ocean habitats.
- Intertidal
- Mangroves
- Mudflats
- Estuaries
- Kelp forests
- Seagrass meadows
- Coral and oyster reefs
- Open ocean
- Tidewater glaciers
- Salt marshes
What are mangroves?
Trees and shrubs that grow near coastal areas and serve as nursing grounds for marine life
What are estuaries?
Areas with mixtures of fresh and salt water
What is a key function of coral reefs?
They contain the most biodiversity out of any aquatic habitat, supporting around 25% of all marine life
What defines an estuarine habitat?
Partly enclosed bodies of water where freshwater mixes with salt water, resulting in brackish waters
What are tectonic estuaries formed by?
Tectonic or volcanic activity
Give an example of a fjord estuary.
Glacier Bay in Alaska
What are the three zones of ponds and lakes?
- Littoral
- Limnetic
- Profundal
What is the littoral zone?
The shallow surface of a lake or pond, the warmest part due to sunlight
Define the limnetic zone.
The open and well-lit area of a lake or pond with mostly plankton and freshwater fish
What characterizes the profundal zone?
It is colder and denser than the limnetic and littoral zones
How are rivers and streams defined?
Water that flows in one direction
What are wetlands composed of?
- Marshes
- Swamps
- Bogs
What are food chains?
Diagrams representing a single pathway of energy flow through an ecosystem
What is the role of producers in a food chain?
They form the base of all food chains
What percentage of energy is typically passed to the next trophic level?
About ten percent
What defines a food web?
Multiple pathways through which energy and matter flow through an ecosystem
What is the first trophic level in a food chain?
Producers
What type of ecological interaction is predation?
One organism kills and feeds on another
What is competition in ecological terms?
When two different species fight for the same resource
Define parasitism.
An interaction where one organism benefits while the host is harmed
What is commensalism?
A one-sided beneficial relationship between two organisms
What is mutualism?
A positive relationship where both species benefit from each other
What is symbiosis?
A relationship where both parties benefit and live in close contact
Define saprophytism.
A mode of life where fungi and bacteria derive energy from dead organic matter
What is the conclusion regarding ecological interactions?
They preserve environments and maintain balance in nature
What are degenerate fungi often regarded as in biological classification?
A third kingdom
This classification separates them from all other classes of living things.
What role do relationships in nature play in the environment?
They preserve environments
Many organisms depend on these relationships to survive.
What is the predator–prey relationship?
A relationship where the predator hunts the prey
This relationship is crucial for maintaining balance in nature.
What is the definition of a host?
An organism that provides nutrition for other organisms while itself being harmed
What is a parasite?
An organism that depends on the host for nutrition
What is a predator?
An organism that hunts and eats another organism
What is prey?
An organism hunted and eaten by a predator
True or False: The predator–prey relationship contributes to maintaining balance in nature.
True
Fill in the blank: The relationships in nature keep the environment in _______.
check
What is one of the biggest contributors to maintaining balance in nature?
Predator–prey relationship
