In deep-sea hydrothermal vents near the Galapagos Islands, bacteria obtain energy by oxidizing hydrogen sulphide released from the vents. Giant tube worms, which lack mouths and digestive systems, harbour the bacteria in their tissues and use them as a source of organic molecules. Clams obtain energy by filtering bacteria directly from the water, and numerous crabs and octopi feed on the clams. In this unique ecosystem, the bactena are playing the role of

#Question id: 10823

#Unit 10. Ecological Principles

Which of the following statements about symbiotic relationships is true?

#Question id: 10824

#Unit 10. Ecological Principles

Interspecific competition has been demonstrated experimentally in

#Question id: 12640

#Unit 10. Ecological Principles

#Question id: 12257

#Unit 10. Ecological Principles

#Question id: 12256

#Unit 10. Ecological Principles

Ant species X preys upon ant species Y. A researcher has the following set of observations regarding the behaviour of species X where aggression signifies a predatory response.

Which of the following statement(s) are correct regarding the behaviour of Species X?

(i)    A glass bead is sufficient to elicit the predatory response.

(ii)   Both chemical and non-chemical cues are involved in the predatory response.

(iii)  Chemical cues are necessary to elicit the predatory response.

(iv) Chemical cues are sufficient to elicit the predatory response

#Question id: 12255

#Unit 10. Ecological Principles

The following three panels show the change in population size over time for two species when they are found alone and when they are found together. Which kind of interaction best describes the relationship between the two species?