HL - 09 - Ecology unit study guide ver 1.0

Flashcards to help you study the topics in the unit study guide.

What is ecology?

The study of how organisms interact with each other and their environment.

What are the levels of ecology?

Population, Community, Ecosystem, and Biosphere.

What is a population?

A group of individual organisms of the same species in the same location capable of interbreeding and producing viable offspring

What is a community?

All of the populations of different species in the same location interacting with each other.

What are biotic factors?

Living components of a community.

What is an ecosystem?

The entire community plus all of the abiotic factors

What are abiotic factors?

Nonliving components such as water, light, wind, soil nutrients, pH, oxygen and other gasses, and salinity

What is the biosphere?

All the ecosystems of the entire surface of the Earth.

What factors increase and decrease population size?

Positive Growth Rate: Natality and Immigration; Negative Growth Rate: Death and Emigration

What is exponential growth?

A population with a positive growth rate and no restrictions to growth will experience exponential growth, forming a J-shaped curve.

What is Carrying Capacity?

Is the maximum population size the environment can support.

What is logistic growth?

Is slowed by limitations and hovers at carrying capacity, graphed as a sigmoid-shaped curve.

How do abiotic factors limit population growth?

Abiotic factors, such as light, water, wind, soil nutrients, pH, temperature, oxygen, and other gasses, can limit population growth.

What are Density-dependent and density-independent factors?

Density-dependent factors worsen with a dense population; density-independent factors limit growth regardless of population density.

What are bottom-up and top-down limits to growth?

Bottom-up limits are due to a shortage of primary producers; top-down limits are due to an overpopulation of predators.

What are Interspecific and intraspecific competition?

Interspecific competition is between different species; intraspecific competition is between members of the same species.

How have humans artificially increased our carrying capacity?

Industrialization, technology, agriculture, medicine, education, and access to cheap energy.

Why do alien species often experience explosive population growth?

Alien species may be better at accessing resources, lack sufficient predation, or possess adaptations allowing them to out-compete others.

What is a Keystone Species?

A keystone species has a disproportionate influence on community structure; its removal or damage would have a ripple effect on the entire community.

What are the four modes of nutrition?

Photoautotroph, Chemoautotroph, Photoheterotroph and Chemoheterotroph.

What are the different types of heterotroph feeding?

Consumers, Decomposers, Detritivores, and Saprotrophs.

What are the types of community interactions?

Competition, Herbivory, Predation, Parasitism and Mutualism.

What is holozoic and mixotrophic feeding?

Holozoic feeding is ingesting food before fully digesting it; mixotrophic feeding is a mixture of photosynthesis and consumption of organic matter.

What primarily determines the niche of a species?

Spatial habitat and interactions with other organisms.

What is a fundamental niche?

The maximum spatial habitat an organism can occupy.

What is a realized niche?

A smaller spatial habitat due to competition.

What is the competitive exclusion principle?

One species may completely out-compete the other, eliminating it from the habitat

What abiotic and biotic factors influence species distribution?

Abiotic: Exposure to water and air; Biotic: Intra- and interspecific competition.

What are obligate aerobes, obligate anaerobes and facultative anaerobes species?

Obligate aerobes require oxygen; obligate anaerobes cannot survive with oxygen; facultative anaerobes prefer oxygen but can survive without it.

What occurs in a zone of stress for an abiotic factor?

Organisms can exist but in fewer numbers or reduced capacity.

What is a line transect and a grid transect?

A line transect runs through the habitat; a grid transect uses an imaginary grid with X and Y coordinates.

When is transects and quadrat sampling an appropriate population estimation method?

It is appropriate for sessile organisms or animals that move very slowly.

What are the limitations to the Capture, Mark, and Recapture (CMR) method?

Tag may come off, animal may be confused for a first capture, animals may die or migrate, public may not report recapture.

What do transects and quadrat sampling chi square test analyze?

Test for association between two species or between a species and an abiotic factor

What does it mean if the chi square calculated number is greater than the critical value?

Reject the null hypothesis and conclude there is association.

What is the Lincoln Index Formula?

Calculation: (Number Marked First Capture x Number Marked Second Capture) / Number Recaptured

What is a food chain?

Food chain shows one particular pathway of feeding in a much larger and complex food web

Who are primary producers?

They are usually photoautotrophs.

How is energy transferred between trophic levels?

An average of 10% of the energy transfers to the next trophic level as new biomass with 90% lost mostly as heat.

What is an energy pyramid?

Diagram of energy flow and biomass in ecosystem; energy lost each level.

How do you calculate the percent efficiency of secondary production?

Calculated by (Total Amount of Assimilated Energy / Energy in Secondary Production) x 100

What is continuously cycled on earth?

Carbon and nutrients.

Why are Nitrogen and phosphorus important?

They are both needed for nucleic acids.

What are Earth's open and closed systems?

Sunlight enters Earth and is lost as heat; carbon, nitrogen, phosphorus, and nutrients are continuously cycled.

What are sinks of static carbon?

Atmosphere, oceans, fossil fuels (oil, coal, peat, and natural gas), limestone, and biomass of living organisms.

What is sequestration?

Capturing carbon dioxide from air or water into a stable sink.

How does carbon exist in ocean waters?

Dissolved carbon dioxide, carbonic acid, carbonate ions, and bicarbonate ions.

What are the major carbon fluxes?

Photosynthesis is the largest flux followed by cellular respiration; others include combustion, forest fires, sedimentation, fossilization, and death.

What are the current levels of atmospheric CO2?

421 ppm

Why does the CO2 concentration zigzag year by year?

Mean CO2 level rises when the northern hemisphere is in winter and falls during summer due to photosynthesis differences

What is anthropogenic climate change?

Long-term alterations in average patterns of temperature, precipitation, wind, and ocean currents caused by human activities.

What are the most impactful human activities on climate change?

Burning fossil fuels, deforestation, industrial agriculture, and meat production.

How does the greenhouse effect work?

Shortwave radiation (UV and visible light) is emitted by the sun, re-emitted by surfaces as longwave radiation (infrared). Greenhouse gasses trap heat.

What is a climate change tipping point?

It is a threshold that, when crossed, will set forth a change of large-scale, accelerated, and potentially irreversible changes to climate systems.

What are the four examples of tipping points?

Alteration of ocean currents, deforestation of the Amazon tropical rainforest, thawing of Boreal permafrost, and melting of glaciers and polar ice sheets.

What is poleward shift?

Warmer temperatures pushing species towards the poles or up mountain sides

What is phenology?

Timing of seasonal events being disrupted due to thermoperiodism

What is the impact of warmer temperatures on insect populations?

Additional life cycles per year causing diseases to spread to new territories

How does climate change and global warming affect evolution of some species?

Disruptive selection causing variations in phenotypes

What is a disturbance in ecology?

Any temporary disruption to the structure and function of an ecosystem.

What is ecological succession?

Process by which a disturbed or new habitat becomes a healthy, stable and established ecosystem.

How are the stages of succession identified?

Each stage being identified by the predominant plant life

What is the plant life succession stages from bare rock?

Annuals, perennials, bushes and small trees, and then taller more sturdy trees

What is cyclical succession?

When an ecosystem undergoes a predictable sequence of changes that return to a similar state over time

What two factors is plant life dependent on?

The mean annual precipitation and temperature

What is a biome?

A collection of many ecosystems with living organisms adapted to the climate conditions of mean annual temperature and rainfall.

What are the four requirements for a stable ecosystem with sustainable climax community?

Consistent energy supply, stable weather patterns, high biodiversity, and healthy nutrient cycling.

What is one way to quantify biodiversity?

Simpson’s Reciprocal Diversity Index formula

How to translate the Simpson’s Reciprocal Diversity Index formula result?

The higher the calculated DI score, the more biodiverse the ecosystem/habitat.

What is a mesocosm?

A recreation of parts of the ecosystem in a smaller container or area that is built and manipulated by scientists.

What is the result of the removal of a keystone species?

It would lead to the demise of the entire ecosystem if it were absent or numbers greatly reduced

What is required for sustainable land use and resources extraction?

There must not be a compromise the stability of the ecosystem

What human activities directly or indirectly lead to extinctions?

Habitat destruction, extraction and burning of fossil fuels, pollution, overharvesting and introduced species

What are three types of disturbances?

Bioaccumulation, eutrophication, and Macro/Micro plastics in the ocean

What is bioaccumulation?

Accumulating in the tissues of animals because they are not excreted with water-soluble wastes by their bodies

What is biomagnification?

The pollutants become increasingly more concentrated in the fat tissues of higher level consumers

What is eutrophication and what is the visible indication?

Excess nitrogen and phosphorus from excessive chemical fertilizers runoff farms into rivers, lakes and oceans where they induce the overgrowth of algae and aquatic plants. The surface is bright green and causes anoxic conditions for the animals in the body of water.

What is conservation?

Any effort to protect, preserve, and restore biodiversity, ecosystems, and natural resources.

What do conservation projects focus on?

Focuses on conserving ecosystem diversity, species diversity, or genetic diversity

What is in-situ conservation?

Conservation efforts take place in the original habitat or location

What is ex-situ conservation?

Some of the last surviving plants or animals must be taken to a facility where captive breeding keeps the species alive and regenerates the population size.