Use the Following Information When Answering the Question Below

question 13

Multiple Choice

Use the following information when answering the question below.
The crucian carp (Carassius carassius) is a Northern European freshwater fish often inhabiting ponds that become hypoxic (have reduced oxygen levels) and even anoxic (have no oxygen) when the surface freezes during the winter.Surprisingly,when oxygen levels are normal,these fish lack the lamellae that provide a large surface area for gas exchange between water and blood: their gills are smooth.Yet when the level of oxygen in the water falls,the gill morphology undergoes a change: packing cells stop dividing and programmed cell death is induced,exposing gill lamellae that were buried in other tissue.With lamellae exposed,the gills have increased surface area for gas exchange.These changes in gill lamellar profile are reversible: investigators observed that the gills return to their normal structure within 7 days after returning the fish to well-oxygenated water.(Jørund Sollid,Paula De Angelis,Kristian Gundersen,and Göran E.Nilsson.2003.Hypoxia induces adaptive and reversible gross morphological changes in crucian carp gills.Journal of Experimental Biology 206:3667-73. )
-Refer to the paragraph on crucian carp.Gills serve multiple functions in fish in addition to gas exchange.Given the large surface area of gills with lamellae,what is the most likely explanation for why crucian carp cover protruding lamellae in their gills when levels of oxygen are normal?

• A)to prevent loss of heat to the surrounding water
• B)to prevent loss of ions to the surrounding water
• C)to prevent protein loss to the surrounding water
• D)to prevent loss of oxygen to the surrounding water

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Definitions:

Gestalt Psychologists

Psychologists who emphasize a holistic approach to psychology, focusing on how people integrate and organize perceptual information into meaningful wholes.

Organized Whole

A principle often related to Gestalt psychology, emphasizing that the total of any given situation or entity is more than the sum of its parts.

Size Constancy

A perceptual phenomenon where the perceived size of an object remains the same, despite changes in the size of the object's image on the retina.

Object Constancy

Correctly perceiving objects as staying the same in their size, shape, color, and lightness, across viewing conditions that yield different physical input to the eyes.