Answers

Explanations

1. Predation takes place when an organism captures and consumes (eats) another organism as a food source. The organism that hunts is called the predator and the organism that is consumed is called the prey.

In this case, the snake is the predator and the rodent is its prey. Therefore, this is an example of predation.

2. In mutualism, both organisms benefit.

In commensalism, one organism is benefits, and the other organism is not harmed nor does it benefit.

In parasitism, one organism benefits while the other organism is harmed.

3. In the human-dog relationship, each species benefits from the other. The human provides food and shelter to the dog who, in turn, provides the human with companionship and often protection. This is an example of a mutualistic relationship.

4. Parasitism is a type of relationship between two organisms in which one organism benefits and the other organism is harmed. The organism that benefits is called the parasite and the organism that is harmed is called the host.

In this case, the tapeworm benefits and the animal is harmed because the tapeworm steals nutrients from animal. Therefore, this is an example of parasitism.

5. Mutualism is a type of relationship or interaction between two organisms that benefits both organisms.

In this case, the crocodile provides a food source (leeches) to the Egyptian Plover by opening its jaws. At the same time, the Egyptian Plover removes harmful parasites (leeches) from the crocodile.

Since both organisms benefit, this is an example of mutualism.

6. Competition exists when two or more different species need the same resource, whether it is food, shelter, water, or sunlight.

In this case, the black bears and the eagles compete for the same food source—fish from the mountain lake.

7. Mutualism is a relationship which benefits both organisms. In this example, the relationship is beneficial to both organisms. The bee gets nectar for food, and the flowers reproduce.

8. Abiotic factors or resources in an ecosystem are the nonliving things, such as air, water, and sunlight.

All of the living things (biotic factors) in an ecosystem depend on abiotic resources to meet their basic needs. For example, a mouse living in a forest ecosystem depends on abiotic factors such as water, air, and a fairly constant temperature.

9. A predator-prey relationship exists when one animal kills and eats another. A coyote eating a hen is an example of a predator-prey relationship.

10. Commensalism is a type of relationship in which one organism benefits and the other organism is neither helped nor harmed. Mites benefit from the interaction with insects they ride on because they get transported from one place to another. The insect that is ridden upon is neither helped nor harmed. Therefore, this is an example of commensalism.

11. Predation occurs when an organism hunts, kills, and consumes another organism for nutrition. The organism that does the hunting is known as the predator. The organism that is killed and consumed is known as the prey.

A wolf hunting, killing, and consuming a deer for nutrition is an example of predation. In this example, the wolf is the predator, and the deer is the prey.

12. Parasitism is a type of relationship between two organisms in which one organism benefits and the other organism is harmed. The organism that benefits is called the parasite and the organism that is harmed is called the host.

In this case, the flea benefits by feeding on the blood of the dog. The dog is harmed because it loses blood and experiences discomfort. Therefore, this is an example of parasitism.

13. Mutualism is a relationship which benefits both organisms. In this example, the relationship is beneficial to both organisms. The ants receive food and shelter, and the tree is protected from animals that might eat it.

In fact, in a study which used pesticide to kill the ants living in an acacia tree, not only were the ants killed, but the acacia tree also died as a result of losing its relationship with the ants.

14. Parasitism is a type of relationship between two organisms in which one organism benefits and the other organism is harmed. The organism that benefits is called the parasite and the organism that is harmed is called the host.

In this case, the mite benefits because it gains transportation from the beetle.

If the weight of the mite slows down the beetle and keeps the beetle from capturing prey, then the beetle is harmed by the relationship. This would be an example of parasitism.

15. Predation occurs when an organism hunts, kills, and consumes another organism for nutrition. The organism that does the hunting is known as the predator. The organism that is killed and consumed is known as the prey.

A wolf hunting, killing, and consuming a deer for nutrition is an example of predation. In this example, the wolf is the predator, and the deer is the prey.

16. Predation takes place when an organism captures and consumes (eats) another organism as a food source. The organism that hunts is called the predator and the organism that is consumed is called the prey.

In this case, the snake is the predator and the rodent is its prey. Therefore, this is an example of predation.

17. A predator-prey relationship exists when one animal kills and eats another. A coyote eating a hen is an example of a predator-prey relationship.

18. Within any environment, organisms with similar needs compete with one another for resources.

If all of the abandoned seashells in a coral reef were occupied by hermit crabs, it would make survival very difficult for the fish that also use those shells for shelter. So hermit crabs and fish that hide in shells compete with each other for shelter.

19. A predator-prey relationship exists when one animal kills and eats another. A coyote eating a hen is an example of a predator-prey relationship.

20. Predation is a type of organism interaction in which one organism, the predator, hunts, kills, and consumes another organism, the prey, for nutrition.

In this case, the wolf is hunting and chasing the deer, so it can eat the deer for nutrition. The wolf is the predator, and the deer is the prey.

21. Abiotic factors, such as rocks, can be an important part of an ecosystem. The rocky cliffs in this ecosystem provide the owl with a place to build a nest that is safe from predators.

If the rocks were removed, the owl population might decrease because more of their chicks could be caught by predators.

22. There are many different types of organism interactions. Some organisms interact with each other for reproductive purposes or for protection. Other organisms interact with each other for nourishment.

For example, a deer might eat a plant (producer-consumer relationship), or a lion might hunt and kill a zebra (predator-prey relationship), or a tick might bite and draw blood from a dog (parasite-host relationship).

In most organism relationships, one organism benefits while the other organism also benefits, is unaffected, or is harmed. Relationships which are helpful to both organisms are known as mutualistic relationships.

The relationship between the African wasp and the fig tree is an example of mutualism. In fact, these organisms are so adapted to one another that one cannot live without the other. The African wasp can only eat nectar from the fig tree; it is unable to gain nourishment from any other source. And, the fig tree can only be pollinated by the African wasp; there is no other insect or organism that can accomplish this task.

23.

Mistletoe lives its entire life on a tree, harming the tree by taking water and nutrients that the tree itself needs. This makes mistletoe a parasite that lives on trees by taking some of the trees' food and water. Mistletoe depends on the tree for life, but the tree does not depend on the mistletoe for anything.

24. Mutualism is a type of relationship or interaction between two organisms that benefits both organisms.

In this case, the bee obtains food from the flower, which the bee uses for energy. At the same time, the bee spreads the flower's pollen, which aids in the flower's reproduction.

Since both organisms benefit, this is an example of mutualism.

25. Predation is a type of organism interaction in which one organism, the predator, hunts, kills, and consumes another organism, the prey, for nutrition.

In this case, the owl is the predator, and the mouse is the prey.

26. Within any environment, organisms with similar needs compete with one another for resources.

Foxes and lynxes are in competition with each other for shelter when they live in the same habitat. In any given mountainous region, there are only a certain number of caves or rocky overhangs that are suitable for medium-sized animals, such as foxes and lynxes. So these two species must compete with each other for the best places to take cover from the weather or to raise their young.

27. In mutualism, both organisms are benefited. In commensalism, one organism is benefited and the other organism is neither harmed nor benefited. In parasitism, one organism is benefited and the other organism is harmed.

28. Yucca trees extend their roots far so that they can have access to as much land as possible. The more land a yucca tree takes up with its roots, the more water it can bring in.

Yucca trees compete with other large plants for this land. Another tree's roots can't take up land already occupied by a yucca tree's roots. The result is that large plants tend to be spaced far apart in deserts.

29. Predation takes place when an organism captures and consumes (eats) another organism as a food source. The organism that hunts is called the predator and the organism that is consumed is called the prey.

In this case, the snake is the predator and the rodent is its prey. Therefore, this is an example of predation.

30. Organisms may interact with each other for a variety of reasons, including nourishment, reproduction, or protection. During these interactions, one organism often benefits from the relationship while the other organism also benefits, is unaffected, or is harmed in some way.

In the predator-prey relationship between the fox and the rabbit, the fox gained nourishment while the rabbit was harmed.