Question

1. classify sort the organisms based on the given descriptions into three categories of symbiotic relationships: mutualism, commensalism, and parasitism.

• fleas live in a rats fur and inject their mouthparts into the rats skin to feed off the rats blood.
• barnacles attach themselves harmlessly to a humpback whales body and receive a steady supply of food from the ocean as the whale swims about.
• cowbirds lay their eggs in other birds nests.
• algae avoid predators by living inside coral tissues and use photosynthesis to provide food for themselves and the corals.

Explanation:

Fleas and Rat

• Step1: Analyze the relationship

Fleas benefit (get food - blood) and the rat is harmed (loses blood, may get infections).

• Step2: Categorize

This is parasitism as one organism (flea) benefits at the expense of the other (rat).

Barnacles and Humpback Whale

• Step1: Analyze the relationship

Barnacles benefit (get food) and the whale is neither helped nor harmed significantly.

• Step2: Categorize

This is commensalism as one organism (barnacle) benefits and the other (whale) is not affected in a major positive or negative way.

Cowbirds and Other Birds

• Step1: Analyze the relationship

Cowbirds benefit (their eggs are incubated and young may be fed by host birds) and the host birds are harmed (waste energy on non - offspring).

• Step2: Categorize

This is parasitism as cowbirds benefit at the expense of the host birds.

Algae and Corals

• Step1: Analyze the relationship

Algae benefit (shelter) and corals benefit (food from algae's photosynthesis).

• Step2: Categorize

This is mutualism as both organisms benefit from the relationship.

Answer:

• Parasitism: Fleas and rat, Cowbirds and other birds
• Commensalism: Barnacles and humpback whale
• Mutualism: Algae and corals