Unit 5 Part 2: Food Chains and Ecology

3 factors that affect the population size

Number of births, number of deaths, number of individuals that enter or leave the population. (birth/death rate).

Population density

Number of individuals per unit of area

What are 3 methods scientists use for ecological succession?

Observing, experimenting, and modeling.

Where is phosphorus found?

On land(in rock and soil minerals), and in ocean sediments.

Decomposers

Organisms that break down and obtain energy from dead organic matter. Organisms responsible for returning the nutrients of dead organisms back to the environment. An organism that breaks down dead organisms and waste.

Greenhouse gases

Natural situation in which heat is retained in Earth's atmosphere by carbon dioxide, methane, water vapor, and other gases.

Biosphere

Nature's houses come in many sizes, this is the largest house. It contains the combined portions of the planet in which all life exists, including land, water, and air or atmosphere.

Food web

Network of complex interactions formed by the feeding relationships among the various organisms in an ecosystem. Many connected, interdependent food chains. Links all the food chains in an ecosystem. A network of interconnected food chains. Diagram that shows the transfer of energy from one organism to another in an ecosystem, staring with a producer and ending with a tertiary or quaternary consumer. Interdependent food chains within an ecosystem.

What factors can limit human population growth?

Death and organisms immigrating

How much energy is available for transfer at each level? Why?

10%. The more levels that exist between a producer and a top-level consumer in an ecosystem, the less energy that remains from the original amounts .

Energy pyramid

A diagram showing the amount of usable energy that is transferred from one trophic level to the next; wider at the base than at the top.

Climax community

A stable community, made of a diverse number of species, that is the result of ecological succession.

What would happen to the organisms ABOVE an organism in a food chain if it went extinct? What would happen to the organisms below it?

ABOVE- They wouldn't have the producer to provide it with all its energy, and eventually, it would go extinct. Below- It would have nowhere to get its energy from, therefore it would die. Increase in number: less energy to use up.

What are the benefits of eating lower on a food chain? Include the benefits to the individual and to the environment.

All of the energy is stored at the bottom of the energy pyramid. The other organisms get less energy. Benefits to individual - has the most energy compare to the other organisms. Environment- That energy will be transferred among the other organisms.

Community

Assemblage of different populations that live together in a defined area.

What do herbivores feed on?

Autotrophs/plants

What do omnivores feed on?

Bi-two-eats both plants and animals

Biodiversity

Biological diversity; the sum total of the variety of organisms in the biosphere.

Biotic

Biological influence on organisms within an ecosystem. Any living thing in an ecosystem.

What factors can slow down a population's growth?

Birthrate decreasing and death rate increasing(occurring at the same rate); and emigration

How is carbon dioxide released into the atmosphere?

By volcanic activity, respiration, human activities(fossil fuels), and by the decomposition of organic matter.

Ecosystem

Collection of organisms that live in a particular place, together with their nonliving, or physical, environment.

Examples of density-dependent limiting factors.

Competition, predation, parasitism, and disease.

What do decomposers feed on?

Dead heterotrophs

Ecological Pyramid

Diagram that shows the relative amounts of energy or matter contained within each trophic level in a food chain or web.

Extinction

Disappearance of a species from all parts of its geographical range

Trophic level

Each step in a food chain or food web. Different levels of producers and consumers in a food chain.

What other energy source do some organisms rely on?

Energy stored in inorganic chemical compounds.

What are nutrients used for?

Every organism needs them to grow and carryout essential life functions. Like water, nutrients are passed between organisms and the environment through biogeochemical cycles.

Limiting Factor

Factor that causes population growth to decrease

Primary Consumer

Feed directly on producers; eat plants or products. Also called herbivores. Second trophic level.

Pioneer Species

First species to populate an area during primary succession

Why is phosphorus important to living organisms?

Forms part of important life sustaining molecules such as DNA and RNA

Niche

Full range of physical and biological conditions in which an organism lives and the way in which the organism uses those conditions. The function ("job") of an organisms in its environment.

3 important characteristics of a population

Geographical distribution, density, and growth rate.

Biome

Group of ecosystems that have the same climate and similar dominant community.

Population

Group of individuals of the same species living in the same area at the same time

Species

Group of organisms so similar to one another that they can breed and produce fertile offspring(reproduce).

S Curve(Logistical Curve)

Growth pattern in which a population's growth rate slows or stops following a period of exponential growth. As resources become less available, the growth of a population slows or stops following a period of exponential growth.

J Curve(Exponential Curve)

Growth pattern in which the individuals in a population reproduce at a constant rate. At first, the number of people increases slowly. Over time, the population becomes larger and larger until it approaches an infinitely large size under ideal conditions with unlimited resources.

Where on the food chain should animals eat in order to gain the most energy? (In other words, where is the "best deal" in terms of energy?)

Herbivore- The environment could support more organisms because there is much more energy present in the plants than in animals.

Global Warming

Increase in average temperatures on Earth

Biological magnification/Biomagnification

Increasing concentration of a harmful substance in organisms at higher trophic levels in a food chain or food web. The increase in concentration of an environmental toxin as you move up the food chain.

Carbon

Key element in living and nonliving matter

Carrying Capacity

Largest number of individuals of a population that a given environment can support.

Density-Dependent Limiting Factors

Limiting factors that depend on population size.

_______(_____) is recycled in an ecosystem and _______ is transferred.

Matter(atoms); energy

What do carnivores feed on?

Mostly animals/fellow heterotrophs

Immigration

Movement of individuals into an area; another factor that can cause the population to grow.

Emigration

Movement of individuals out of a population; another factor that can cause a population to decrease in size.

Producers

Organisms that can capture energy from sunlight or chemicals and use it to produce food from inorganic compounds; also called an autotroph. Organisms that make their own food; essential to flow of energy through biosphere. Can be found in first trophic level.

Secondary Consumer

Organisms that feed on primary consumers. Third trophic level.

Tertiary Consumer

Organisms that feed on secondary consumers. Fourth trophic level.

Quaternary Consumer

Organisms that feed on tertiary consumers. Fifth trophic level.

What do detritivores feed on?

Organisms that once were to decompose

Consumers

Organisms that rely on other organisms for their energy and food supply; also called a heterotroph. Organisms that obtain food and energy by eating other organisms. Organisms that acquire their energy from other organisms by feeding on them, decomposing organisms that are now dead, etc. There are different levels of consumers. Each level is called a trophic level. Consumers are also called carnivores or omnivores.

__________ within an ecosystem require a constant supply of _______(____) to maintain their life processes.

Organisms; energy(food)

What are the possible consequences of continuing human population growth?

Overpopulation and food shortages

What four elements make up 95% of the bodies of most organisms?

Oxygen, carbon, hydrogen, and nitrogen.

Abiotic

Physical, or nonliving, factor that shapes an ecosystem.

Invasive species

Plants and animals that have migrated to places where they are not native

What happens to the carbon dioxide in the atmosphere?

Plants take it in and use it for photosynthesis, build carbohydrates. The carbohydrates are passed onto animals, who rely on it for energy.

What is light energy used for in photosynthesis?

Power chemical reactions that convert carbon dioxide and water into oxygen and rich-energy carbohydrates such as sugars and starches.

Symbiosis

Relationship in which two species live closely together

What factors have allowed the human population to experience exponential growth?

Reproduction and emigration

Food chain

Series of steps in an ecosystem in which organisms transfer energy by eating and being eaten. Show flow of energy in an ecosystem. A relationship among organisms in which each is linked to another that eats, absorbs, or decomposes.

Which organisms use chemosynthesis?

Several types of bacteria

_____ energy is collected and converted into _________ energy by producers.

Solar; chemical

Important note about consumers on trophic levels:

Some organisms are at different levels. For example, when a squirrel eats acorns or fruit, it is a primary consumer; when it eats insects, it is a secondary consumer.

Territory

Specific area occupied and protected by an animal or group of animals

What is the general shape of an exponential growth curve?

Steep, positive graph, steady increase, J.

Describe the direction of energy flow from the Sun.

Sun/Inorganic Compounds---->autotrophs----->heterotrophs

The ultimate/main energy source for all organisms on Earth is...

The Sun

Eutrophication

The aging process of a lake (either occurring naturally or artificially fast due to human interference).

Habitat

The area where an organism lives, including the biotic and abiotic factors that affect the organisms.

Ecological Succession

The gradual replacement of one plant and animal community by another through natural processes over time.

Biogeochemical Cycles

The process of elements, chemical compounds, and other forms of matter are passed from one organism to another and from one part of the biosphere to another. They connect biological, geological, and chemical aspects of the biosphere.

Ecology

The scientific study of interactions among organisms and their environment, or surroundings. Origin: created by Ernst Haeckl, who saw the living world as a household, each organism plays a role.

What do biological systems do with matter?

They do not use it up, they transform it. The matter is assembled into living tissue or passed out of the body as waste products.

Why do omnivores sometimes "throw off" an energy pyramid's ideal shape (a perfect triangle)?

They eat both producers and consumers.

Where do humans fit in most food webs?

Top- Omnivores, apex predators, all types of consumers(tertiary levels 1, 2, and 3).

How does energy flow differ from the flow of matter?

Unlike the one-way flow of energy, matter is recycled within and between ecosystems.

Calories

Way of maintaining energy. different ways of consuming the same amount of calories per day on each trophic level.

Chemosynthesis

When organisms use chemical energy to produce carbohydrates.

The elk consumes carbon in the carbohydrates he consumes. Describe 2 ways the carbon in the elk's body will be put back into the carbon cycle.

When the elk breathes, carbon is released for the plants to use during photosynthesis. When the elk dies, carbon will be broken down by decomposers, and recycled by calcium carbonate. Calcium carbonate is formed, breaks down organic materials, and it is released into the atmosphere again.

What are the roles of scavengers and decomposers in a food web?

Without them, it wouldn't be a cycle. They break down the complex inorganic compounds into simple nutrients. This creates energy that can be reused in the soil. The cycle starts over again. Break down dead organisms and move nutrients into soil - new generation of plants begins.

The amount of energy available at each ________ ______ is directly related to the number of _____ in a food chain.

trophic level; links

The amount of _______ energy in an ecosystem _________ with higher trophic levels.

usable; decreases