Ecosystems Unit Study Guide
What is necessary for life?
In order to have live you must have oxygen, food, water, and shelter.
Are all organisms important?
Yes, all organisms are important. Without one the others would die as shown in the illustration below.
What are the steps to the flow of energy going through a food chain?
Sunlight – producers – consumers – decomposers
The sunlight helps to mushrooms to grow, the caterpillar eats the mushrooms, the bird eats the caterpillar, the cat eats the
bird, eventually the cat will buried after he/she passes, and its body will be decomposed by decomposers
Why is a food web called a food web and not a food chain?
In a food chain each organism is only eat by one animal but in reality must animals have multiple predators. As seen in
the diagram below the phytoplankton is each by three different ocean species, the species that eat the phytoplankton are
eaten by seven different animals.
If an animal dies out in a food chain, everything that follows it will die out very quickly. In a food web, if a species dies out,
the organism next in line could find another food source.
Why do all food chains and food webs start with the sun?
The sun is the source of all energy for our solar system. All food chains and food webs must start with the sun because
the sun gives producers (plants) the energy to grow.
Why do organisms become extinct?
An organisms could become extinct for many reasons including, but not limited to: their habitation being destroyed, water
drying up, all the food source is eaten or died out, the organism was unable to adapt to a climate/habitation change.
How does the population affect the number of plants and animals?
If an animal population grows too large the plants population could die out. In reverse, if all the plants in one area die the
animal population will be forced to adapt to a new type of food, move, or the animal population will die out.
What makes an animal a consumer?
A consumer is an organism that has to consume (eat) other plants or animals in order to survive. Examples include
caterpillars, wolfs, lions, giraffe, cow, horse, etc.
What makes a plant are producer?
An organism is considered a producer if it can make its own food, usually by using sunlight and water to do so. Examples
include trees, flowers, vegetables, fruits, and any plants.
What do decomposers feed on?
Decomposers feed on the remains of other animals. Most are so small they cannot be seen but some examples include
mushrooms, bacteria, and fungi.
What do herbivores, omnivores, and carnivores feed on and what is their role?
Type
Role
Explanation
Herbivore
consumer
eats producers (plants)
Omnivores
consumer
Carnivores
consumer
eats both plants and
animals (meat)
eats only animals (meat)
Examples
cow, sheep, squirrel, deer,
bee, some people
bears, birds, lizards, mice,
some people,
cheetah, frog, hawks,
sharks, bats, seals
How do external features tell you about the ability of the animal? Some features include:
having a hard shell (turtle because it has a very soft body)
light color if they are in the sun all day (lizards) or dark color if they are usually in the dark (sea creatures or bats)
camouflage skin so the animal blends into its normal surroundings (stick bug is brown to blend into sticks/branches)
changing skin color, whatever the animal touches, it will turn it body color to that to stay hidden (many sea creatures)
How do different organisms survive?
Different organisms survive by using camouflage to hid themselves from predators, hibernation to stay alive during long
winters, or using their external features (see above question).
How do organisms determine what to eat?
Organisms know what to eat by their using their natural instincts or watching their mothers/parents.
Key Vocabulary:
scarce
predator / prey
adaptation
animal product
competition
ecosystem
food chain
food web
hibernation
omnivore
variation
producers
consumers
decomposers
organisms
camouflage
protection
reproduce
community
flow of energy
herbivore
survival
survival of organisms
carnivore
extinction
population