Mimicry is an important long-term evolutionary survival adaptation. In nature, there are four main types of mimicry used by species to enhance their survival. Batesian mimicry occurs when a palatable species closely resembles an unpalatable one. Müllerian mimicry exists when several unpalatable species resemble one another. Mertensian mimicry occurs when a deadly predator mimics a less dangerous one. Last, crypsis is the result of camouflage that enables a species to closely resemble its environment.

Current studies have indicated that the visually similar viceroy and monarch butterflies are equally poisonous to predators. This is an example of which type of mimicry?

     Species competition is driven by a variety of factors. Resources such as water, food, sunlight, and suitable habitat are among the top contributors that influence interspecific and intraspecific competition. Interspecific is competition between different species and intraspecific competition is between members of the same species.

     One interesting example of interspecific completion is that of two barnacle species that inhabit intertidal zones. Balanus balanoides inhabits the lower intertidal zone and Chthamalus stellatus inhabits the lower intertidal zone. A researcher attempts to study this phenomenon.

     The researcher removes the Balanus species from the lower intertidal zone and observes that the Chthamalus species expands its range to inhabit the lower intertidal zone and the upper intertidal zone. The researcher then removes the Chthamalus species from the upper tidal zone of a different area and observes that the Balanus species does not extend its range. The researcher concludes that competition has allowed each species to exist simultaneously by forming specialized niches that promotes survivorship for each species.

A researcher suggests that the barnacles behave in this manner because of the presence of a keystone species. A keystone species is a species that promotes species diversity by way of actions or behaviors. Which of the following could be a keystone species in the barnacles' environment?

     Species competition is driven by a variety of factors. Resources such as water, food, sunlight, and suitable habitat are among the top contributors that influence interspecific and intraspecific competition. Interspecific is competition between different species and intraspecific competition is between members of the same species.

     One interesting example of interspecific completion is that of two barnacle species that inhabit intertidal zones. Balanus balanoides inhabits the lower intertidal zone and Chthamalus stellatus inhabits the lower intertidal zone. A researcher attempts to study this phenomenon.

     The researcher removes the Balanus species from the lower intertidal zone and observes that the Chthamalus species expands its range to inhabit the lower intertidal zone and the upper intertidal zone. The researcher then removes the Chthamalus species from the upper tidal zone of a different area and observes that the Balanus species does not extend its range. The researcher concludes that competition has allowed each species to exist simultaneously by forming specialized niches that promotes survivorship for each species.

Ecologists have found that the lower intertidal zones possess far greater levels of carbon dioxide than the upper regions. What does this evidence suggest?

Symbiosis is defined as a state in which two species intimately live together. This indicates that they are in close contact with one another and can affect each other. Symbiosis has been documented in three dominant forms: commensalism, mutualism, and parasitism. Commensalism exists when one organism benefits and one, presumably the host, is affected neither negatively or positively. Mutualism is described as two organisms that both benefit from their interactions. Last, parasitism is described as an interaction that benefits an organism at the expense of the host organism.

Barnacles adhere to the bodies of whales in the ocean. The barnacle is granted transportation, possible food sources, and shelter. The relationship does not seem to enhance or negatively impact the whale's survival. This is an example of which type of symbiosis?

Symbiosis is defined as a state in which two species intimately live together. This indicates that they are in close contact with one another and can affect each other. Symbiosis has been documented in three dominant forms: commensalism, mutualism, and parasitism. Commensalism exists when one organism benefits and one, presumably the host, is affected neither negatively or positively. Mutualism is described as two organisms that both benefit from their interactions. Last, parasitism is described as an interaction that benefits an organism at the expense of the host organism.

Bacteria live in the digestive tract of humans and other mammals. The bacteria enable the the host to better digest food and in return are granted a suitable habitat and a source of food. This is an example of which type of symbiosis?

Symbiosis is defined as a state in which two species intimately live together. This indicates that they are in close contact with one another and can affect each other. Symbiosis has been documented in three dominant forms: commensalism, mutualism, and parasitism. Commensalism exists when one organism benefits and one, presumably the host, is affected neither negatively or positively. Mutualism is described as two organisms that both benefit from their interactions. Last, parasitism is described as an interaction that benefits an organism at the expense of the host organism.

A dog ingests a tapeworm. The worm feeds off of the host dog while at the same time deprives the host of much needed nutrients. This is an example of which type of symbiosis?

Symbiosis is defined as a state in which two species intimately live together. This indicates that they are in close contact with one another and can affect each other. Symbiosis has been documented in three dominant forms: commensalism, mutualism, and parasitism. Commensalism exists when one organism benefits and one, presumably the host, is affected neither negatively or positively. Mutualism is described as two organisms that both benefit from their interactions. Last, parasitism is described as an interaction that benefits an organism at the expense of the host organism.

Honey bees pollinate flowers while at the same time harvesting nectar to be made into honey. This is an example of which type of symbiosis?

     Osmoregulation is a necessary function to maintain homeostasis in organisms. Fish gills form the boundary between fish body fluid and environmental conditions. The regulation of water transport across barrier epithelial membranes in gills is assisted by membrane composition and affected by solute concentration on either side of the membrane. Fish body fluids are isotonic and have compositions of about 300 milliosmoles of solutes per liter. Freshwater environments are hypotonic and typically have compositions of about 1 milliosmole of solutes per liter. Saltwater environments are hypertonic and typically have a composition of about 1,000 milliosmoles of solutes per liter. Based on observed osmoregulation across varying concentration gradients, it is expected that gills exposed to isotonic solutions maintain steady water weight, while those exposed to hypotonic solutions increase in water weight, and those exposed to hypertonic solutions decreased in water weight.

Study 1

     Gills dissected from a fish were exposed to different ambient environments of salinity including an isotonic control solution (301.5 milliosmoles), a hypotonic solution (1.5 milliosmoles), and a hypertonic solution (601.5 milliosmoles). Percent water weight change between treatments was observed and calculated.

A homeowner purchases a fish species that can survive in either salt or freshwater environments. The homeowner has several tropical fish living in a saltwater tank. The purchased fish was placed in a bag containing an isotonic solution. The shop clerk states that the fish should be placed in a particular solution before being placed in the saltwater environment. Which solution should the fish be placed in before it is put in the tropical tank?

     Osmoregulation is a necessary function to maintain homeostasis in organisms. Fish gills form the boundary between fish body fluid and environmental conditions. The regulation of water transport across barrier epithelial membranes in gills is assisted by membrane composition and affected by solute concentration on either side of the membrane. Fish body fluids are isotonic and have compositions of about 300 milliosmoles of solutes per liter. Freshwater environments are hypotonic and typically have compositions of about 1 milliosmole of solutes per liter. Saltwater environments are hypertonic and typically have a composition of about 1,000 milliosmoles of solutes per liter. Based on observed osmoregulation across varying concentration gradients, it is expected that gills exposed to isotonic solutions maintain steady water weight, while those exposed to hypotonic solutions increase in water weight, and those exposed to hypertonic solutions decreased in water weight.

Study 1

     Gills dissected from a fish were exposed to different ambient environments of salinity including an isotonic control solution (301.5 milliosmoles), a hypotonic solution (1.5 milliosmoles), and a hypertonic solution (601.5 milliosmoles). Percent water weight change between treatments was observed and calculated.

A tropical-fish store places fish in saltwater environments. Over several months a large number of fish die in the tanks. The shop owner takes one of the fish to a research lab where its cells are analyzed. The researchers tell the owner that the fish cells burst due to the solute concentration of its environment. Compared to the fish's gills the environment was of which of the following salinities?

Carbonic anhydrase is an enzyme that is used by the human body to interconvert carbon dioxide (a gaseous compound) and bicarbonate (a compound composed of hydrogen, carbon, and oxygen), using water as a reactant. The human body needs to convert carbon dioxide to bicarbonate in the tissues to transport it in the blood to the lungs, as carbon dioxide is relatively insoluble. In the lungs, bicarbonate is converted back to carbon dioxide to be exhaled. In humans, there are two different carbonic anhydrase isomers, one that works in the lungs (isomer A) and one that works in the tissues (isomer B). Mutations in the chromosomes can prevent carbonic anhydrase from converting carbon dioxide to bicarbonate. In the following four experiments, the chromosomes of none, one, or both of the isomers were mutated per experiment.

Experiment 1

Radiation was used to mutate one of the chromosomes of one or more isomers of carbonic anhydrase. A probe was placed into the tissues and lungs of a model animal. Bicarbonate was measured in the tissues but carbon dioxide was not measured in the lungs.

Experiment 2

Radiation was used to mutate one of the chromosomes of one or more isomers of carbonic anhydrase. A probe was placed into the tissues and lungs of a model animal. Carbon dioxide levels were found to be abnormally high in the tissues and no bicarbonate was measured in the lungs.

Experiment 3

Radiation was used to mutate one of the chromosomes of one or more isomers of carbonic anhydrase. A probe was placed into the tissues and lungs of a model animal. Carbon dioxide levels were found to be slightly low in the tissues and bicarbonate levels were abnormally high in the lungs.

Experiment 4

Radiation was not used, A probe was placed into the tissues and lungs of a model animal and found normal carbon dioxide and bicarbonate levels.

Which of the following best describes the role of carbonic anhydrase in the tissues?