Biosphere Exam Flashcards
This is the term describing the permanent loss of a species resulting in an overall decreases in biodiversity
Extinction
Evidence that life existed in the past is called
Fossil
Net primary productivity is…
The rate at which producers use photosynthesis to produce and store chemical energy minus the rate at which they use this energy through aerobic respiration
True or False? Organisms with a narrow niche are generally resistant to environmental changes?
False
During what geologic age did animals suddenly diversify?
Cambrian
The concept that species have changed over long periods of time is known as:
Evolution
Arrange in order of least to most complex, the levels of biological organization
Organisms, population, community, ecosystem
True or False? Terrestrial biomes are defined primarily by their climatic factors, mainly temperature and precipitation, and the biological community that inhibits them
True
Which of the following is a primary producer?
Algae
Carbon takes between ________ years to move between rocks, soil, ocean, and atmosphere in the slow carbon cycle
100-200 million
An ecological “niche” can be defined as _______.
The role an organism plays in its community
True or False? Metabolism is the set of chemical reactions by which an organism derives energy for life processes
True
What are the main components of the fast carbon cycle?
Primary producers
Removal of which of the following from a community will have the greatest effect to the community structure?
Keystone species
Why is it difficult to pull nitrogen from the atmosphere into the nitrogen cycle of the biosphere?
Few organisms can “fix” atmospheric nitrogen gas
What is the ultimate source of energy for most surface ecosystems of present-day earth?
Sunlight
Which of the following populations is most like to go extinct?
Small population in an unstable environment
Biodiversity is a measure of:
The variety of special within an ecosystem
The habitable zone of the solar system includes which planets?
Earth alone
Prokaryote
Single-celled organisms that contain DNA and RNA within a cell well, but lack a membrane-bound nucleus and mitochondria
Cyanobacteria
Cell that lack a true membrane-bound nucleus, contain chlorophyll a, and perform photosynthesis
Eukaryote
Cells that lack a true membrane-bound nucleus, contain chlorophyll a, and perform photosynthesis
Virus
Contain DNA and RNA but have no cell walls; they are parasitic infectious agents that reproduce when they infect a suitable host
Biome
A major regional ecological community characterized by distinctive life forms and principal plant or animal species, such as a tropical rain forest, a tundra, a grassland, or a desert
Ecosystem
A community of organisms and their physical environment that interact as an ecological unit
Population
Any group of individuals, usually of a single species, occupying a given area at the same time
Community
Any grouping of populations of different organisms that live together in a particular environment
r-selected species
Species that produce many offspring, each with less chance of survival to adulthood, but potentially more adaptable to unstable environments
K-selected species
Species that invest in fewer offspring, each with a better chance of survival to adulthood in stable environments
Explain what the nitrogen paradox is
The ‘paradox’ of nitrogen is that 78% of the atmosphere is nitrogen, but this is inaccessible to most organisms. Only specialized microbes and humans have figured out how to access atmospheric nitrogen and use it as a nutrient
