SAT II Biology E : Types of Interspecies Relationships

Study concepts, example questions & explanations for SAT II Biology E

varsity tutors app store varsity tutors android store

Example Questions

Example Question #1 : Types Of Interspecies Relationships

Which of the following are reasons why invasive species are often successful?

I. Lack of competition

II. Lack of predators

III. Specialized diet

Possible Answers:

I only

I and III only

II and III only

II only

I and II only

Correct answer:

I and II only

Explanation:

Lack of competition and predators allow invasive species to thrive and increase in population number. While diet may affect a population's success in inhabiting a new environment, it is not necessarily a reason for increased success in invasive species.

Example Question #5 : Ecology

Remoras are fish that use their sucker-like mouths to attach onto the skin of other animals. They often attach to sharks and consume dead skin cells, any food discarded from the shark, and other organisms that may feed on the shark itself. The relationship between the shark and the remora is an example of which of the following?

Possible Answers:

Commensalism

Competition

Decomposition

Parasitism

Predation

Correct answer:

Commensalism

Explanation:

This is an example of commensalism as one species benefits (the remora) and the other species is not affected (the shark). The remora gains food and has to use little energy to obtain that food whereas the shark does not notice the small remora riding on its skin. The remora does not prey on the shark, the two are not in competition with each other because the remora consumes discarded food, and the remora does not harm the shark, so it is not a parasite. 

Example Question #2 : Types Of Interspecies Relationships

Which of the following is true about competition?

Possible Answers:

One species will eventually out compete the other and thus one species will go extinct.

Competition is only temporary and does not result in a loss of fitness.

Competition can occur within a species and between species.

Competition refers to two individuals directly interacting in a way that prevents one individual from accessing a resource.

The term only refers to animals and not plants.

Correct answer:

Competition can occur within a species and between species.

Explanation:

The term refers to all living organisms and can directly or indirectly lower the fitness of the other individual. A competitor may or may not go extinct. It is also possible that one species or community will exploit a slightly different niche over time to avoid competition or lessen its effects or the affect of competition may be enough to reduce population numbers but not cause the species to go extinct entirely.

Example Question #7 : Ecology

Which of the following exemplifies a mutualistic relationship?

Possible Answers:

Algae and sunlight

Dogs and fleas

Ospreys and fish

Bees and flowers

Barnacles and whales

Correct answer:

Bees and flowers

Explanation:

A mutualistic relationship is a type of interspecies interaction in which both of the participating organisms gain some sort of benefit. In this case, the bee benefits by receiving food from the flower in the form of nectar. The flower, in turn, is provided with a means of pollination when the bees transport pollen from flower to flower as they gather nectar. Barnacles and whales is an example of commensalism, since the barnacles benefit without either helping nor harming the whales. Dogs and fleas is and example of parasitism, since the dog is harmed while the fleas benefit. Ospreys and fish is an example of a predator-prey relationship, as the osprey hunts the fish for food. Algae and sunlight is not a viable choice for a mutualistic relationship as the sun is not an organism.

Example Question #3 : Types Of Interspecies Relationships

Which of the following describes a symbiotic relationship between two organisms in which one organism benefits and the other is harmed?

Possible Answers:

Mutualism

Divergent evolution

Parasitism

Commensalism

Competition

Correct answer:

Parasitism

Explanation:

Mutualism, parasitism, and commensalism are all symbiotic relationships (close, long-term interactions between two species). Parasitism correctly describes a symbiotic relationship in which one organism benefits and another is harmed (for example, giardia is a parasite found in contaminated water that can live in human intestines and cause gastrointestinal distress). Mutualism describes a relationship in which both species benefit from the interaction. Competition describes an interspecies (or intraspecies) relationship in which two species (or two members of the same species) occupying the same habitat compete for resources and the fitness of one species is harmful to the other (for example, two male deer competing to establish a dominance hierarchy or an invasive plant species taking nutrients from a native species). Commensalism describes a relationship in which one organism benefits and another organism neither benefits nor is harmed (for example, a cattle egret eating insects as it follows grazing cattle). Divergent evolution is not an interspecies relationship but an evolutionary concept by which the accumulation of differences between groups can lead to the formation of new species, often due to species diffusion to different, isolated environments.

Learning Tools by Varsity Tutors

Incompatible Browser

Please upgrade or download one of the following browsers to use Instant Tutoring: