Ecology Flashcards
What is a community?
A community is the “group” formed when
all the different populations of species
share the same habitat.
What is biodiversity?
ALL living things represents the Biodiversity of a habitat!
How is biodiversity measured?
Biodiversity is measured using 2 components:
1. Species Richness: total number of species in the community
2. Relative Abundance: the number of each species in relation to the total organisms in the community.
What makes for HIGH Biodiversity?
1) The species richness is high.
2) The relative abundance of different
species is similar/dissimliar.
What is an Ecosystem?
An Ecosystem is a community of species interacting in a given environment.
This includes the abiotic factors of the habitat, such air, soil, water, etc
Micro-habitat: Examples
- Tree stump
- Aquarium
Macro-habitats: Examples
- Caribbean ocean
- African planes
Trophic Relationships can be represented by:
A food chain
How many trophies levels are there?
Three
What are the three tropic levels?
1) Producer
2) Consumer
3) Decomposer
Dynamics of an ecosystem:
How does energy flow?
What are food chains?
Representations of the trophic relationships between different living
things.
What are food webs?
A group of interrelated food
chains.
Which direction do arrows point?
In the direction of energy, food to mouth.
What is energy flow?
Matter and energy are transferred/transformed in a food
chain.
What is biomass?
All of the organic matter in an ecosystem
What does biomass represent?
The total mass of living matter in an environment at any given time.
With each tropic level, energy and biomass…
decrease
Why does energy and biomass decrease with each trophic level?
Organisms give off energy to breathe, eat, reproduce, move etc.
What do trophic levels affect?
Relative abundance and population size for
the whole ecosystem to remain in balance!
With each trophic level increase
10% of energy/biomass is lost
What are producers?
Autotrophs, they produce their own food.
What do producers do?
Producers convert inorganic matter into organic material.
A principal mechanism includes production of sugar: photosynthesis.
What are Cyanobacteria?
They are producers. They were the first unicellular organism to produce energy in
Earth’s history.
What is primary productivity?
is the total quantity of new organic material made by the producers in an ecosystem over a certain period.
It depends on factors: sunlight, CO2 concentration, nutrient availability, water, and temperature.
In what condition do plants and algae produce the most matter?
Between 20-25 degrees Celsius.
Productivity is highest in warm and humid areas.
What are consumers?
Heterotrophs because they get their food
from a variety other living things.
What consumers are there?
Primary - Herbivores, feed on producers or their seeds
Secondary and Tertiary - Carnivores, Feed on animals on the level below them
Omnivores, consumers of all levels at once.
What are decomposes?
They feed on dead matter and/or (some
feed on) waste of producers &
consumers
This connects them to all of the trophic
levels!
Fungi and Bacteria.
What is chemical recycling?
Chemical Recycling occurs when decomposers make inorganic matter available in an ecosystem by breaking down organic matter.
At each trophic level in a food chain a certain amount of material is recycled by decomposers back into nutrients that producers can use.
What is the Law Of Conservation of Matter
Matter can not be created nor destroyed, it can only be transferred or transformed.
What is a Disturbance?
A Disturbance is an event that disrupts an ecosystem. It can lead to the elimination
of organisms (extinction) and change the availability of resources.
What are the two types of disturbances?
- Natural
Disturbances occur due to
environmental phenomena such as: - Human Disturbances are
the main form of ecological
disturbance on Earth
What is ecological succession?
The series of changes that occur over time in an ecosystem after a disturbance and that continue until the balance of the ecosystem is restored.
What is an ecological footprint?
An ecological footprint is the estimate of how much of the available resources we consume and how much waste we generate.
How do you calculate ecological footprint?
+ Land and water used to produce goods and services
+ Land and water used to dispose of waste
+ Land and water occupied
How to Calculate the Happy Planet Index?
HPI = (Experienced well being x Life expectancy) / Ecological footprint
What is Ecotoxicology?
Human activities disturb ecosystems.
These include industrial and agricultural activities and the creation of waste which releases different substances or poisons into the environment.
What are contaminants?
They are many type of substances or radiation that is likely to cause harm to one or more ecosystems.
What are the 4 classes of contaminants?
- Inorganic
- Organic
- Microbial
- Radioactive
What is the Toxicity Threshold?
The Toxicity Threshold is the amount of a
contaminant that will cause harm in an
organism. Harm from contaminant can range from mutations to fertility loss to death.
What Factors Determine Toxicity?
1) Concentration
2) Type of organism (how doe it affect the bio chemistry)
3) Duration of exposure
What is dosage dependent on?
Weight!
What is a toxicity threshold?
Toxicity Threshold is the minimum level of
concentration at which the contaminant causes harm (mg/kg).
What is a lethal dose?
Lethal Dose is the amount of contaminant necessary to kill an organism in a single dose.
What is LD Fifty
Lethal Dose Fifty (LD50) is the dose that causes the death within 50% of individuals.
What is Bio/accumulation/concentration/ magnification?
- It is the degree to which a
toxin can accumulate in a
living organism through
inhalation, ingestion
and/or dermal exposure. - These contaminants resist
natural degradation and
cannot be eliminated.
Bioaccumulation, Bioconcentration or Biomagnification: Example of Degree of Intoxication
- Once the contaminated producer (plant) is consumed, the toxin can become stored in the fat tissues of the consumer.
- The consumers must consume A LOT of producers causing the concentration of the toxin to be accumulated in the consumer than in the producer and so on.
What is Bioremediation?
- Biotechnology can help fix
some of our past mistakes. - We can take certain microbes / biological species add them to a region that has
particular contaminants and have them degrade them. This considered
bioremediation.
