Environmental Studies/Ecosystem

Population grow in two ways

"S" curve "J" curve

Flower

reproductive organ of angiosperm plants especially one having showy or colorful parts

climax community

species composition no longer changes over time; secession stops. Community retains an overall uniform appearance.

Sporangium

spore capsule in which haploid spores are produced by meiosis

hydrosere

succession in freshwater lakes

lithosere

succession on bare rock

halosere

succession on salt marshes

psammosere

succession on sand dunes

pioneer communities

the first organisms to colonize (or recolonize) an area.

Dynamic equilibrium

there is no specific 'average' state; the system has different average states at different times. After a disturbance, the system may move to a different 'average' state.

Abiotic Factor

The non-living parts of an organism's habitat

population

A group of organisms of the same species living in the same area at the same time, and which are capable of interbreeding.

species

A group of organisms that interbreed and produce fertile offspring.

community

A group of populations living and interacting with each other in a common habitat.

Succession

(Def: The change in vegetation in an area over time (or sometimes over distance)

Carrying Capacity

(Def: The number of organisms a particular area can support) If organisms exceed the carrying capacity; a negative feedback loop occurs - organisms eat all the food = no food leads to dying out

Growth Rates

(Def: The time a population takes to grow by a particular percentage) It often depends on population density. populations grow fastest at low population densities (e.g., birds of prey, limited by prey availability) -Intermediate density (locusts need reasonable densities to reproduce etc.) -High Densities (seabirds less vulnerable to predators when in large group) Fastest growth rates have quickest response to change; slow growth has slow response to changes

Generation Time

(Def: The time taken for an individual to reach sexual maturity, and produce offspring)

K-selection

- Long-lived - Few offspring per reproductive period - Reproduce later in life - Nurture young - Relatively large

r-selection

- Short-lived - Large broods - Reproduce early in life - Little to no care for young - Relatively small

photosynthesis

6CO2 + 6H2O + light energy ⇒ C6H12O6 + 6O2 + heat - Carbon Dioxide, Water and Sunlight go in, Glucose, Oxygen and Heat are produced.

Haploid

A cell with a single set of chromosomes (23 in humans), in humans this is usually in gametes. This is commonly represented by n.

Diploid

A cell with two sets of chromosomes (46 in humans). This is commonly represented by 2n.

ecosystem

A community of interdependent organisms and the physical environment they inhabit.

Ecosystem

A community of plants and animals that live in a particular area, along with their nonliving surroundings

Biome

A group of land ecosystems with similar climates and organizsms

biotic factor

A living, biological factor that may influence an organism or ecosystem, such as producers-plants,consumers-animals etc

abiotic factors

A non-living or physical factor that may influence an organism or ecosystem. For example, precipitation, wind, sunlight, soil, temperature, pH, salinity, light, temperature

Invasive Plant Species

A non-native plant species that causes economical or environmental harm

niche

A species' share of a habitat and the resources in it. An organism's ecological niche depends not only on where it lives but on the role it plays in the ecosystem.

Equilibrium

A state of balance among the components of a system

Primary Succession

After a volcanic explosion/glacial scrape Dust accumulates on rock surface, seeds begin to grow.

Habitat

An environment that provides the things an organism needs to live, grow, and reproduce.

Decomposer

An organism that breaks down waste and dead organisms and returns the raw materials to the ecosystem

Producer

An organism that makes its own food. The source of all food in an ecosystem

Consumer

An organism that obtains energy by feeding on another organism.

respiration

C6H12O6 + 6O2 ⇒ 6CO2 + 6H2O + released energy (heat) - Glucose and Oxygen go in, Carbon Dioxide and Water and Heat are produced.

Heterotrophs

Decomposers -

Grass-forbs

Dominated by small grass and small shrubs

First Law of Thermodynamics: Conservation of energy

Energy cannot be created or destroyed, only transformed from one form to another. There is a fixed amount of energy in the universe. Therefore living organisms must get their required energy from their environment and surroundings.

Cell

Fundamental structural unit of all living things

Biotic Factor

The living part of an ecosystem

Vital Signs

Gulf of Maine Research Unit

Predators

How many? Food availability - how much, where (is there need to travel?), is it difficult to obtain food? Habitat availability - are they specialists/generalists?, can they live anywhere?, Is their habitat being degraded? Reproduction - are mates easy to find? does it require much effort?

"J" curve

Large populations build up over time and then crash before building up again. Common in population of primary consumers, in communities with few species where extreme abiotic (physical) factors may control population growth. Also, natural predators are few, or completely absent.

Nucleus

Membrane-bound organelle which contains the chromosomes

Producers/Autotrophs

Organisms that make their own food. Usually plants through photosynthesis. Primary consumers - Organisms that consume producers. Secondary consumers - Organisms that consume primary consumers.

Strategies for Survival

Numbers ("r") large number of offspring no parental care short pregnancy breed when young pioneers niche generalists e.g., insects, fish Investment ("k") late maturity specialists (niche) mainly predators high trophic level (generalization) adapted to stable environment e.g., elephants, dolphins

Organism

Obtains the food, water, shelter, and other things it needs to live, grow, and reproduce from its environment.

Herbivores

Organisms that eat plants, but no meat. Carnivores - Meat-eaters. Omnivores - Organisms that eat both plants and meat.

Factors affecting populations

Predators Carrying Capacity Growth Rates Generation Time "J" curve Succession

Can be

Primary Succession (from bare earth) or Secondary Succession (disturbed land recovering)

Secondary Succession

Recovering growth from disturbed lands

Native Plant Species

Species of plants that arrive in Maine without human intervention

Non-Native Plant Species

Species of plants that were brought to Maine intentionally for horticulture or other uses, or came accidentally by crop seed or soil.

Stable equilibrium

The condition of a system in which there is a tendency for it to return to a previous equilibrial condition following disturbance

Steady-state equilibrium

The condition of an open system in which there are no changes over the longer term, but in which there may be oscillations in the very short term. There are continuing inputs and outputs of matter and energy, but the system as a whole remains in a more-or-less constant state.

Water Cycle

The continuous process by which water moves from Earth's surface to the atmosphere and back

habitat

The environment in which a species normally lives.

fundamental niche

The part of the habitat in which a species can live in the absence of competitors and predators

realized niche

The part of the habitat that the organism actually occupies.

Trophic level

The position that an organism occupies in a food chain, or a group of organisms in a community that occupy the same position in food chains. And is mainly considered as feeding level.

Shrubs-seedlings

Trees appear on the scene and begin to dominate. The shade intolerant species grow rapidly and dominate over shade tolerant species.

Sapling-pole

Trees dominate and out-compete shrubs

Reproductive Strategies

r and K

Second Law of Thermodynamics: In an isolated system entropy tends to increase spontaneously.

When energy is converted from one form to another, some of the energy is degraded into less-usable heat which disperses into the environment. Thus the amount of energy remains the same, but its usability decreases.

mutualism

[+ , +] Both species benefit

parasitism

[+ , -] One species benefits, the other is harmed. The host is killed slowly if at all.

predation

[+ , -] One species benefits, the other is harmed. The prey is usually killed quickly.

competition

[- ,-] Two species (interspecies competition) or two populations of the same species (intraspecies competition) compete for the same resources. Both sides are harmed.

commensalism

[0 , +] One species benefits, the other is unaffected

amensalism

[0 , -] One species is harmed, the other is unaffected

succession

a change over time in the types of species that occupy a given area.

system

a collection of interrelated parts that work together by way of some driving process.

Seed

a mature fertilized plant ovule consisting of an embryo and its food source and having a protective coat or testa

sere

a sequence of communities over ecological time. Each stage of succession is called a seral stage.

Glycerol

a sweet syrupy trihydroxy alcohol obtained by saponification of fats and oils

Exoenzyme

an enzyme used to break down organic molecules outside the body

Hydrocarbon

an organic compound that contains carbon and hydrogen only.

Autotroph

an organism which can make its own energy

Heterotroph

an organism which can not make its own energy

Eukaryote

an organism with a nucleus

Prokaryote

an organism with no nucleus

Ether

any of a class of organic compounds that have two hydrocarbon groups linked by an oxygen atom

Ecosystems

are the biotic and abiotic factors in a specified area that interact with one another.

symbiosis

biological interaction where two different species are in direct contact with each other.

Understanding the interaction of the biotic and abiotic factors in an ecosystem

can help us to see why particular human activities may be a problem for human survival. Example: The loss of ozone in the stratosphere increases the quantity of UV radiation on the surface of the planet. In the same way that humans experience sunburn from too much sun exposure, so do plants. Excessive UV may damage or destroy plant protein and DNA, killing the plant.

Ecosystem

collection of all the organisms that live in a particular place, together with their nonliving environment

primary succession

ecological succession in an environment that has not been previously inhabited (no soil is present).

secondary succession

ecological succession in an environment that was exposed to some type of disturbance (soil is already present).

surroundings

everything around the system being studied

open system

exchanges energy and matter with surroundings. Most ecosystems are open.

closed system

exchanges energy but not matter with surroundings. Our planet is [usually] closed.

isolated system

exchanges neither energy nor matter with surroundings. Laboratory experiments are usually isolated.

Lipid

fatty acid esters which form the basis of cell membranes

This is the first stage in the succession process

hardy, small colonizers (typically less complex organisms) Usually occurs in dry environments with plenty of sunlight

"S" curve

initial slow growth, as population increases limiting factors such as food supply, slow growth rate. Levels out as the population approaches the carrying capacity.

biome

large, relatively distinct terrestrial region characterized by similar climate (temperature and precipitation), soil, and organisms.

Tracheid

long tubular cell peculiar to xylem

Entropy

measures the amount of disorder in the universe - usable energy is more organized whereas less-usable energy is more diffuse/disorganized. Entropy increases naturally, or spontaneously.