Name: _______________________________________ Test Date: ____________________Period: ____________
Chapter 1 “Interactions of Living Things” Study Guide
1. What are the 5 levels of organization in the environment? Put them in order from the first to the fifth level and give
an example for each one.
Organism – a single duck
Population – all the ducks in a given ecosystem
Community – all the different species in a ecosystem, like all the ducks, and all the grass, and all the birds, etc.
Ecosystem – all the species that were included in the community plus all of the abiotic factors such as temperature,
wind, sun, water, etc.
Bioshpere – all of Earth where living things exist.
2. What is the difference between abiotic and biotic factors? Give three examples for each.
Abiotic factors are nonliving, such as wind, water, temperature, pH, sun, rocks, dirt, etc.
Biotic factors are all the living things in an ecosystem, such as birds, grass, glowers, fish, deer, etc.
3. When you are looking at a food chain or a food web, what do the arrows show? Who do they point to?
The arrows show who is receiving the energy. They point toward the organism DOING the eating, or the one who
is receiving the energy.
4. What are the three ways for living things to obtain energy? Give an example for each type.
Consumer – any organism that eats another organism; a lion eating a zebra or a human eating an apple
Producer – any organism that can make its own food, typically using the sun; like plants using photosynthesis to
make their own food.
Decomposer – any organism that breaks down dead matter and absorbs the nutrients; like bacteria and fungus
decomposing dead leaves or organisms.
5. What are the three types of consumers? Explain the difference between the three types and give an example for each.
Carnivore – eats only other animals – a wolf, lion, hyena, etc
Herbivore – eats only plants – a cow, bison, ladybug, etc.
Omnivore – eats both plants and animals – like a human, bear, etc.
6. Explain the following types of symbiotic relationships and provide an example for each type.
Mutualism: A relationship where both individuals benefit. An example is the bacteria in your intestines. The
bacteria gain a meal and you benefit because they help with your digestion.
Commensalism: A relationship where one organism benefits and the other is unaffected. An example is the
remora fish and sharks. The ramoras attach to the shark to get a free ride and to eat any scraps that fall from the
sharks kill. The shark has no benefit from the fish being there.
Parasitism: A relationship where one organism (the parasite) gains nourishment from another organism (the host).
The parasite gets food, and the host is harmed or even killed. An example is the mosquito and the human. The
tick gets food and the human is harmed.
7. What is a carrying capacity?
Carrying capacity it the maximum number of individuals that any ecosystem can support at one time.
8. What is a limiting factor?
Any resource that controls how many organisms can be successful in any environment
9. When there isn’t enough food in an ecosystem, what does that lead to in organisms?
When there isn’t enough food to go around, it leads to competition among different species or within the same
species.
10. Give some examples of predator and prey adaptations.
lion and zebras, coyotes and deer, hawks and mice, etc. The animal doing the eating is the predator and the one
being eaten is the prey
11. When the close interaction between two organisms results in long term changes in both organisms _coevolution___ has
taken place.
12. When looking at an energy pyramid, explain why only 10% of available energy is passed to the next level.
Organisms use 90% of available energy to perform their life processes. Only 10% is store in their tissues and can be
passed on to the next level.
13. Explain what happened to the ecosystem in Yellowstone National Park when the gray wolf population declined.
When the gray wolf population declined, nothing was hunting the elk in the area. This led to a large increase in the
number of elk. They overgrazed the grass so that there wasn’t enough food for the other animals relying on the grass
for food. The energy flow in the entire ecosystem was affected.
14. What is the difference between a population and a community?
A population contains only one species, while a community contains all of the different species in an ecosystem
15. Explain what the difference is between a predator and a prey?
the predator hunts and eats the prey. (The prey is eaten by the predator)
16. What is the difference between a predator and a decomposer?
A predator hunts another living thing for food. A decomposer breaks down dead organisms so that they can absorb the
available nutrients.
17. Why do limiting factors determine an ecosystem’s carrying capacity?
Because there are only so many resources to go around. If there is not enough of any type of resource then organisms
suffer and perhaps migrate or die. The amount of individuals that can survive in any given environment (the carrying
capacity) is always determined by how much resources are available for the organisms living there.