Unit 2
Biomes
-Aquatic Biomes -Marine Biomes -Freshwater Biomes -Terrestrial Biomes
Succession: Changes over Time
-Ecologists refer to the orderly, natural changes and species replacements that take place in the communities as successions -Succession occurs in stages; different species at different stages create conditions that are suitable for some organisms and unsuitable for others. -It can take decades, or even centuries, for one type of community to completely succeed another. -Primary and secondary successions
Energy and trophic levels: Ecological pyramids
-Ecologists use food chains and food webs to model the distribution of matter and energy within an ecosystem, and they also use an ecological pyramid. -The base of the pyramid represents the first trophic level, higher trophic levels are layered on top of one another. -The initial source of energy for all three ecological pyramids is the sun -When an organism consumes food is uses some if the food for metabolism some for building tissue and energy lost enters the environment as heat.
The nonliving environment: Abiotic factors
-Ecology also includes the study of feauteres of the environment that are not living because this are important part of an organisms life -The nonliving parts of an organism's environment are the abiotic factors -Abiotic factors have obvious effects on living things nd often determine which species survive in a particular environment.
Cycles in nature
-Energy is always being replenished -Mater also moves through the organisms at each trophic level but it cannot be replenished like the energy from sunlight, it is constantly recycled
Food chains: Pathways for matter and energy
-Food chain is a simple model that scientists use to show how matter and energy move through an ecosystem. -Nutrients and energy proceed from autotrophs to heterotrophs and to decomposers -Food chain consist of tree link but most have no more that five links -Many kinds of organisms eat a variety of foods, so a single species may feed at several trophic levels
Biodiversity (Bill Nye Notes)
-In order to ecosystem to be successful it needs to be biodiversity -Living things make holes everywhere they can -¾ of earth's surface is cover with water -They depend on each other to live -Things that live on the ecosystem depend on each other they are attached -Ecosystem is made up of animal and plants that live together -Two thirds of the species live in the ocean
The living environment: Biotic factors
-Living organisms affect other organism -All the living organisms that inhabit an environment are called biotic factors, and ecologists investigate how this affects different species -Ecologists organize the world into levels
The producers: Autotrophs
-Plants use the sun to manufacture food this process is called photosynthesis -Organisms that use energy from the sun or energy stored in chemical compounds to manufacture their own nutrients are called autotrophs
Living relationships
-Some species enhance their chances of survival by forming relationships with other species -Some interactions are harmful for one specie, but beneficial to other -When there is a close and permanent association among organisms of different species is called symbiosis -There are several symbiotic relationship like; commensal relationship, Mutualism relationship, and parasitism relationship
The phosphorus cycle
-Substances such as phosphorus must also cycle through an ecosystem -All organisms require phosphorus for growth and development -Plants obtain phosphorus from soil -When they die phosphorus returns to the soil and is used again -Phosphorus also has a long cycle
Ranges of tolerance
-The ability of an organism to withstand fluctuations in biotic and abiotic environmental factors is known as tolerance. -Some species can tolerate conditions that another species cannot.
How organisms obtain energy
-The ultimate source of the energy is the sun, which supplies the energy that fuels life.
The consumers: Heterotrophs
-There are some organisms that cannot make their own food, they need to feed themselves with other organisms they are called Heterotrophs -A heterotroph that only feed on plants is called a herbivore -Animals that eat other animal are called carnivores -Humans are an example of the third type of heterotroph -We eat animal and plant material that is called omnivores -Organisms that break down and absorb nutrients from dead organisms are called decomposers
The effects of the tide
-Twice a day, the gravitational pull of the sun and moon causes the rise and fall of ocean tides. -Intertidal ecosystems have high levels of sunlight, nutrients, and oxygen, but productivity may be limited by waves crashing against the shore
Cycles
-Water cycle -Carbon Cycle -Nitrogen Cycle -Phosphorus Cycle
Matter and Energy Flow in Ecosystems
-When you grab an apple from the tree it contains energy trapped by the tree -Ecologists study these interactions to make models that trace the flow of matter and energy through ecosystems
A mixing of water
-Wherever rivers join oceans, freshwater mixes with saltwater. -Because of all the changes in the salinity, a wide range of organisms can live in estuaries. -These small organisms attract wide range of predators, including cranes and other birds -Dead organisms proceed quickly, recycling nutrients through food web
Patterns of population growth
-an organism's reproductive pattern, helps determine population growth, and answer different questions -the kind of reproductive pattern a species has depends mainly on environmental conditions -species that live in more stable environments, such as elephants, often have a different life.history pattern -rapid life-history patterns are found in organisms from unpredictable environments -organisms that have a small body size, mature rapidly, reproduce early, and have a short life span
Environmental limits to population growth
-limiting factors also regulate the size of a population -there are two kinds of limiting factors: density dependent and density-independent factors -density dependent factors have an increase effect as the population increases -in very dense populations, disease may quickly wipe out an entire population -most density-independent factors are abiotic factors such as temperature, storms, floods, etc.
Limits of the environment
-population growth has limits -limiting factors, such as food and space, will cause a population to stop increasing -when populations are under the carrying capacity of a particular environment, births exceed deaths until the carrying capacity is reached -when population falls below the carrying capacity, the population increases, and when it is above the carrying capacity, the population decrease
Principles of Population Growth
-population growth is defined as an increase in the size of a population over time -one method involves placing microorganisms, such as bacteria into a tube and observe how rapidly the population grows -one method involves introducing an organism in a new environment that contains many resources and then observe the population growth of that specie
Organism Interactions Limit Population Size
-population sizes are limited not only by abiotic factors, but also are controlled by various interactions among organisms that share a community
How fast do pospulations grow?
-populations of organisms do not experience linear growth -the initial increase in the number of organisms is slow because the number of reproducing organisms is small -soon, the rate of population growth increases rapidly, because the total number of potentially reproducing organisms increase -exponential growth results in a population explosion
Food chain
A simple model that scientists use to show how matter and energy move through an ecosystem.
Climax Community
A stable, mature community that undergoes little or no change in species
Mutualism
A symbiotic relationship in which both species benefit
Parasitism
A symbiotic relationship in which one organism derives benefit at the expense of the other
Density-Independent factor
Affect all populations, regardless of their density.
Biotic Factors
All the living organisms that inhabit an environment.
Carnivores
And animals that kill and only eat other animals.
Plankton
Are small organisms that live in the waters of the photic zone
The portion of Earth that supports life is the
Biosphere
Correct order form largest to smallest
Biosphere Ecosystem Community Population Organism
What is not a type of symbiosis?
Decomposers
Aphotic Zone
Deeper water that never receives sunlight
Name one Biome in the world
Desert
Trophic Level
Each organism in a food chain represents a feeding step, or trophic level, in the passage of energy and materials.
Limiting Factors
Environmental factors that affect an organism's ability to survive in its environment, such as food availability, predators, and temperature
Food Web
Expresses all the possible feeding relationships at each trophic level in a community.
Herbivore
Feeds only with plants
An elk eats grass. A grizzly bear eats the elk. This is n example of a
Food chain
Density-dependent factor
Include sease, competition, parasites, and food.
Estuary
Is a coastal body of water, partially surrounded by land, in which freshwater and saltwater mix.
Community
Is a collection of interacting populations.
Population
Is a group of organisms.
Biome
Is a large group of ecosystems that share the same type of climax community
Commensalism
Is a symbiotic relationship in which one species benefits and the other species is neither harmed nor benefited
Ecosystem
Is made up of the interactions among the populations in a community and the community's physical surroundings, or abiotic factors.
Habitat
Is the place where an organism lives out its life
Biosphere
Is the portion of earth that supports life.
Niche
Is the role and position a species has in its environment.
Ecology
Is the scientific study of interactions among organisms and their environments.
When focusing a specimen, you should always stet with...?
Low shortest objective
What is true concerning the flow of energy and matter in an ecosystem?
Matter is recycled and used again, energy is lost
Exponential Growth
Means that as a population gets larger, it also grow faster
Successions
Orderly, natural changes and species replacements that take place in the communities of an ecosystem
Decomposer
Organisms that break down and absorb nutrients from dead organisms.
Heterotroph
Organisms that cannot make their own food and must feed on other organisms.
Scavenger
Organisms that do not kill for food; instead, they eat animals that have already died.
Omnivores
Organisms that eat both animals and plants.
Autotroph
Organisms that use energy from the sun or energy stored in chemical compounds to manufacture their own nutrients.
Symbiosis
Predators are animals such as lions and insect eating birds that which there is a close and permanent association among organisms of different species
Secondary Successions
Refers to sequence of community changes that takes place after a community is disrupted by natural disaster or human actions
What is the main source of energy for all organisms in a food web?
Sun
Primary Successions
The colonization of new sites like these by communities of organisms
Abiotic Factors
The nonliving parts of an organism's environment.
Carrying Capacity
The number of organisms of one species that an environment can support
Photic Zone
The portion of the marine biome that is shallow enough for sunlight to penetrate
Intertidal Zone
The portion of the shoreline that lies between the high and low tide lines