Ecology Essential Standard 12A Retake

Four common relationships between organisms are listed below.

1. Bees pollinate plants as they move flower to flower gathering nectar.

2. Green algae grow on the backs of spider crabs living in shallow water, camouflaging the spider crabs while the crab protects the algae from predators.

3. Fleas live on the skin of dogs and obtain nutrients from the dogs’ blood.

4. Nitrogen-fixing bacteria obtain nutrients from their host plants and use the nutrients to supply nitrogen to the plants.

Which statements best describe these relationships?

• Relationships 1 and 4 are examples of mutualism.

  Relationship 2 is an example of commensalism.

  Relationship 3 is an example of parasitism.

• Relationships 1 and 2 are examples of commensalism.

  Relationships 3 and 4 are examples of mutualism.

• Relationship 1 is an example of commensalism.

  Relationship 2 and 4 are examples of mutualism.

  Relationship 3 is an example of predation.

• Relationship 1, 2, and 4 are examples of mutualism.

  Relationship 3 is an example of parasitism.

Parrotfish are herbivores that are found in coral reefs. To escape predation, a parrotfish will graze with a rabbitfish, which has venomous spines at the end of its pelvic fins. The rabbitfish does not benefit from this relationship. Which type of relationship do the parrotfish and the rabbitfish have in the coral-reef environment?

• Commensalism

• Mutualistic

• Predation

• Parasitism

In any environment or ecosystem, organisms can have several different types of relationships.

Three types of relationships are described below.

Relationship X – Hermit crabs live in shells made and then abandoned by snails.

Relationship Y – Mistletoe extracts water and nutrients from the oak tree, causing harm to the oak tree.

Relationship Z – Algae and fungi live together, forming lichen. The algae produce carbohydrates through photosynthesis, providing nutrients to both the algae and the fungi. The fungi provide moisture for the algae.

Which of these correctly describes the relationship between the organisms?

• X: Mutualism

  Y: Parasitism

  Z: Commensalism

• X: Commensalism

  Y: Parasitism

  Z: Mutualism

• X: commensalsim

  Y: Mutualism

  Z: Parasitism

• X: Parasitism

  Y: Commensalism

  Z: Mutualism

Commensalistic interactions between species are rare. Which of the following is an example of this type of symbiotic relationship?

• intestinal worms in a dog

• a bee pollinating a buttercup flower

• barnacles attached to a whale

• the roots of two neighboring cacti

In the tropical regions of Africa, the crocodile lies with its mouth open. The plover flies into its mouth and feeds on bits of decaying meat stuck in the crocodile’s teeth. The crocodile does not eat the plover. Instead, he appreciates the dental work. The plover eats a meal and the crocodile gets his teeth cleaned. Coincidentally, the Egyptian plover is also known as the crocodile bird.

• Predation

• Commensalism

• Mutualism

• Parasitism