Ecosystems

Ecosystems

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Ecosystems

• •An ecosystem is made up of a community of organisms and

  the non-living environment.

• Ecosystems are made up of living things (biotic factors) and non-living things (abiotic factors), which are connected to each other in complex interrelationships.

Multiple Choice

What are the ecological levels of organization from smallest to the largest?

• organism, population, community, ecosystem, biome, biosphere
• organism, community, population, ecosystem, biome, biosphere
• organism, population, community, biome, ecosystem, ecosphere.
• organism, community, population, biome, ecosystem, ecosphere

Multiple Choice

What are groups of different populations living togther in the same place at the same time called?

• An organism
• A population
• A community
• A biosphere

Multiple Choice

What is it called when a group of the same organisms living together in the same place at the same time?

• An organism
• A population
• A community
• A biome

Biotic & Abiotic

• The living components of the ecosystem are called biotic factors, which include plants, fish, invertebrates, and single-celled organisms.

• •The non-living components, or abiotic factors, include  the physical and chemical components in the environment—temperature, wind, water, sunlight, and oxygen.

• Biotic and abiotic factors influence each other in an always changing balance called dynamic equilibrium

Multiple Choice

Why is a stick that broke off a tree still considered a bitoic factor?

• because it was once living

• because it was never living

Multiple Choice

what is a biotic change

• the increase in rainfall in the amazon

• the decrease in rain in the amazon

• the increase in rocks on the ground

• the decrease in plant population

Multiple Choice

temperature is an example of...

• a biotic factor

• an abiotic factor

• none of the above

• a biotic factor

Multiple Choice

Living or once-living organisms in an ecosystem are called ________________________ _________________________.

• biotic factors

• abiotic factors

• nonbiotic factors

Interactions in an Ecosystem

• An ecosystem is a complex network of interactions.

• All organisms must take in water, food, and nutrients. Nutrients are elements and compounds that organisms need to live and grow.

• In all environments organisms with similar needs may compete with each other for resources, including food, space, water, air, and shelter

Limiting Factors

• a property of a population’s environment – living or nonliving – which controls the process of population growth.

• •Biologists have identified two major types of limiting factors:

  –Density-dependent factors

  –Density-independent factors

• 
  

Ecosystem Components

• Niche

• Habitats

• Competitive Exclusion Priniciple

Niche

• organism’s occupation (role), where it lives, and way in which organism’s use conditions they exist in

  –Food it eats

  –Place in food web

  –How it gets food

  –Range of temperatures  needed for survival

  –When and how it reproduces

Multiple Choice

What would happen if the population of hawks suddenly increased? How would it affect the other organisms in the ecosystem?

• The snakes would decrease due to more hawks eating them
• All of the population of organisms would increase
• The biotic factors in the ecosystem would increase
• The hawks predators would decrease

Multiple Choice

What are some abiotic factors that could be limiting factors in the Iowa River ecosystem?

• Temperature, fertilizer runoff from fields, drought or flood

• Invasive species, floods

• Temperature, predators, droughts, floods, over fishing

Multiple Choice

What will happen if all of the frogs in a population die?

• The frogs' predators will decrease and the frogs' prey will increase

• The frogs' predators will increase and the frogs' prey will decrease

• We better all pray because there isn't anymore frogs.

Multiple Choice

Limiting factors are sometimes helpful because they can keep the population from getting too large.

• True
• False

Multiple Choice

Any thing or organism that regulates the size of a population of another organism is known as __________.

• a limiting measure
• a limiting factor
• factorization
• materialization of precipitation

Habitats

• Physical environment to which an organisms has become adapted and survives in.

Competitive Exclusion Principle

• Two different species cannot occupy the same niche in the same geographic area.

• If they do they will compete with one another for the same food and other resources

• Eventually, one species will out compete the other

Multiple Choice

What is a niche?

• Where an organism lives.

• An organisms role, or job, within its habitat.

• What an organism eats.

• Knights who say funny words.

Multiple Choice

In the woods, there are hawks and robins. They both try to occupy the same niche by competing for worms as the only source of food in that same area at that same time. The hawks outcompete the robins, and the robins are forced to leave that area. This is an example of:

• Mutualism

• The competitive exclusion principle

• Commensalism

• Neutralism

Multiple Choice

As populations grow, they tend to spread out into new territory. Which limiting factor is most likely to become an issue?

• Food

• Shelter

• Space

• Water

Multiple Choice

A certain species of snake in an ecosystem consumes frogs, salamanders, and small rodents. Which change in the ecosystem will MOST likely cause an increase in the snake population?

• A new species that eats frogs enters the ecosystem

• The population of small rodents in the ecosystem decreased.

• The kinds of insects that salamanders eat increase in number

• A kind of animal that eats the snake species increases in number

Multiple Choice

Populations of wolves and rabbits in an ecosystem are represented by the graph below.

Which best explains the relationship between wolves and rabbits in the ecosystem?

• As the number of rabbits increases, the number of wolves increases

• As the number of rabbits increases, the number of wolves remains constant

• As the number of rabbits decreases, the number of wolves increases

• As the number of rabbits decreases, the number of wolves remains constant

Multiple Choice

Which would most likely happen to a local population of owls if their food source of field mice were eliminated?

• The owls would immediately starve to death

• The owls would prey on another similar animal as a food source

• The owls would begin eating berries found in the same habitat area

• The owls would live off stored fate reserves until mice returned to the area

Multiple Choice

Overall, all the interactions between organisms in ecosystems...

• Keep ecosystems & populations unstable and random

• Keep ecosystems & populations stable and balanced