TF阅读真题第970篇Sea Life Adaptations in the Deep Ocean

题目：

Sea Life Adaptations in the Deep Ocean

 

Marine scientists identify several zones within the ocean’s vertical water column, from the sunlit surface to the deep, dark floor. In the top layer, enough sunlight penetrates to allow photosynthesis and support a community of abundant life. Below the sunlit zone is the mid-water level, called the mesopelagic zone, which receives only dim sunlight. Fish and other creatures in the mesopelagic zone have adapted to low light and low oxygen levels.  

Common adaptations among hunters in the mesopelagic zone are sensitive eyes and other light-detecting organs that perceive outlines and movement at low light levels. Typically, such devices are a hundred times more sensitive to light than human eyes. Predators and prey tend to adopt camouflage strategies that involve body transparency, color patterns and photophores (light-producing organs) that break up the body outline, or, as in the case of hatchet fishes, a body flattened from side to side to yield only a narrow silhouette when viewed from below.

Creatures living in the upper part of the mesopelagic, where light intensities are higher, are more likely to be transparent. Zooplankton that penetrate the deeper levels of the mesopelagic are commonly orange, red, or purple but in the blue-green background light are perceived as black or inconspicuous gray. Some mesopelagic fish have elongate(long and narrow) bodies, which may be a means of extending the length of the lateral line-a vibration-detecting organ -thereby raising sensitivity for detecting predators or prey.

Most mesopelagic animals are bioluminescent. This ability has evolved many times by different mechanisms. Some organisms, such as the lantern fishes and bristlemouths, produce their own light, utilizing specialized tissue that is adapted for this purpose. Others, such as certain species of cod, harbor light-producing symbiotic bacteria that are cultivated inside special light organs. Whatever the precise mechanism, biologically generated light is produced within living cells and energy is released in the form of light rather than heat; bioluminescence is cold light. In some creatures, particularly translucent or transparent zooplankton such as jellyfish and ctenophores, the reactions occur in scattered cells called photocytes. In others-particularly fish and squids–light- producing photophores are employed. Blue or green and, less commonly, yellow are the customary colors of bioluminescent light.

Bioluminescence serves a variety of functions. As described earlier, photophores can be used by fish and squid as a form of camouflage to break up the body outline and as counter illumination to match background light levels. Some lantern fishes probably use light organs to improve visibility when seeking prey. In at least some lantern fishes, the location and pattern of light flashes is probably used to communicate between individuals within a species and to distinguish between sexes and aid in selecting a mate. Many creatures use bioluminescence for defensive purposes; large gelatinous animals such as jellyfish, ctenophores, and salps produce an explosive burst of bioluminescence across the body when disturbed. This presumably serves to blind or distract the predator temporarily. Some jellyfish, ctenophores, and squid shed luminescing tentacles when attacked. A few squid and octopuses produce bioluminescent ink to dazzle and confuse attackers while they escape under cover. Some zooplankton-particularly copepods, ostracods, and shrimps-squirt a bioluminescent fluid as defense.

In many parts of the ocean where bacteria and krill congregate in high densities to feed on suspended particulate material, their metabolic activities deplete the water of available oxygen, thereby creating the oxygen-minimum layer. Those organisms that exploit the detritus in this layer or feed on other organisms found there must cope with low oxygen levels. The fish, the krill, and the shrimp associated with this layer characteristically have large gills and blood that is highly efficient at absorbing any available oxygen. Typically, such animals are also sluggish and adopt an opportunistic policy rather than actively hunting for prey. This way, they conserve energy and reduce their oxygen requirement. Their skeleton and musculature are reduced, and their body shape and form is subordinated to the need to remain floating in the water column with the minimum of muscular effort.

 

 

 

 

 

 

1

Common adaptations among hunters in the mesopelagic zone are sensitive eyes and other light-detecting organs that perceive outlines and movement at low light levels. Typically, such devices are a hundred times more sensitive to light than human eyes. Predators and prey tend to adopt camouflage strategies that involve body transparency, color patterns and photophores (light-producing organs) that break up the body outline, or, as in the case of hatchet fishes, a body flattened from side to side to yield only a narrow silhouette when viewed from below.

According to paragraph 2, all of the following help predators in the mesopelagic zone survive EXCEPT

 

Negative Factual Information Questions否定事实信息题

 

Alight-detecting organs

Bthe ability to see prey passing under them

Ca flat body

Dcolor patterns that disguise the body outline

2

Common adaptations among hunters in the mesopelagic zone are sensitive eyes and other light-detecting organs that perceive outlines and movement at low light levels. Typically, such devices are a hundred times more sensitive to light than human eyes. Predators and prey tend to adopt camouflage strategies that involve body transparency, color patterns and photophores (light-producing organs) that break up the body outline, or, as in the case of hatchet fishes, a body flattened from side to side to yield only a narrow silhouette when viewed from below.

The word “perceive” in the passage is closest in meaning to

 

Vocabulary Questions词汇题

 

Afollow

Bevaluate

Csee

Dreact to

3

Creatures living in the upper part of the mesopelagic, where light intensities are higher, are more likely to be transparent. Zooplankton that penetrate the deeper levels of the mesopelagic are commonly orange, red, or purple but in the blue-green background light are perceived as black or inconspicuous gray. Some mesopelagic fish have elongate(long and narrow) bodies, which may be a means of extending the length of the lateral line-a vibration-detecting organ -thereby raising sensitivity for detecting predators or prey.

In paragraph 3, the author discusses mesopelagic fish with elongate bodies in order to

Rhetorical Purpose Questions修辞目的题

Aprovide an example of how deep-sea organisms increase their sensitivity to light

Bargue that extending the length of the lateral line helps animals blend in with their surroundings

Cexplain the relationship between body shape and body transparency

Ddescribe an alternative to eyesight for detecting other animals in dark waters

4

Most mesopelagic animals are bioluminescent. This ability has evolved many times by different mechanisms. Some organisms, such as the lantern fishes and bristlemouths, produce their own light, utilizing specialized tissue that is adapted for this purpose. Others, such as certain species of cod, harbor light-producing symbiotic bacteria that are cultivated inside special light organs. Whatever the precise mechanism, biologically generated light is produced within living cells and energy is released in the form of light rather than heat; bioluminescence is cold light. In some creatures, particularly translucent or transparent zooplankton such as jellyfish and ctenophores, the reactions occur in scattered cells called photocytes. In others-particularly fish and squids–light- producing photophores are employed. Blue or green and, less commonly, yellow are the customary colors of bioluminescent light.

Why does the author mention that “certain species of cod, harbor light-producing symbiotic bacteria that are cultivated inside special light organs”?

 

Rhetorical Purpose Questions修辞目的题

 

ATo explain how photocytes work

BTo differentiate between cold light and warm light

CTo emphasize the variety of ways bioluminescence can be produced

DTo describe the most common mechanism for producing bioluminescence

5

Most mesopelagic animals are bioluminescent. This ability has evolved many times by different mechanisms. Some organisms, such as the lantern fishes and bristlemouths, produce their own light, utilizing specialized tissue that is adapted for this purpose. Others, such as certain species of cod, harbor light-producing symbiotic bacteria that are cultivated inside special light organs. Whatever the precise mechanism, biologically generated light is produced within living cells and energy is released in the form of light rather than heat; bioluminescence is cold light. In some creatures, particularly translucent or transparent zooplankton such as jellyfish and ctenophores, the reactions occur in scattered cells called photocytes. In others-particularly fish and squids–light- producing photophores are employed. Blue or green and, less commonly, yellow are the customary colors of bioluminescent light.

According to paragraph 4, which of the following is true about bioluminescence in transparent or translucent zooplankton?

 

Factual Information Questions事实信息题

 

AReactions occur in photocytes dispersed throughout the organisms

BUnlike in most other bioluminescent organisms, the light is yellow

CReactions occur in light-producing organs called photophores

DIt is produced by symbiotic bacteria like in some species of cod

6

Bioluminescence serves a variety of functions. As described earlier, photophores can be used by fish and squid as a form of camouflage to break up the body outline and as counter illumination to match background light levels. Some lantern fishes probably use light organs to improve visibility when seeking prey. In at least some lantern fishes, the location and pattern of light flashes is probably used to communicate between individuals within a species and to distinguish between sexes and aid in selecting a mate. Many creatures use bioluminescence for defensive purposes; large gelatinous animals such as jellyfish, ctenophores, and salps produce an explosive burst of bioluminescence across the body when disturbed. This presumably serves to blind or distract the predator temporarily. Some jellyfish, ctenophores, and squid shed luminescing tentacles when attacked. A few squid and octopuses produce bioluminescent ink to dazzle and confuse attackers while they escape under cover. Some zooplankton-particularly copepods, ostracods, and shrimps-squirt a bioluminescent fluid as defense.

According to paragraph 5, lantern fishes may use bioluminescence for all of the following purposes EXCEPT

 

Negative Factual Information Questions否定事实信息题

 

Achoosing a mate

Bcommunicating with other lantern fish

Cfinding prey

Descaping from predators

7

Bioluminescence serves a variety of functions. As described earlier, photophores can be used by fish and squid as a form of camouflage to break up the body outline and as counter illumination to match background light levels. Some lantern fishes probably use light organs to improve visibility when seeking prey. In at least some lantern fishes, the location and pattern of light flashes is probably used to communicate between individuals within a species and to distinguish between sexes and aid in selecting a mate. Many creatures use bioluminescence for defensive purposes; large gelatinous animals such as jellyfish, ctenophores, and salps produce an explosive burst of bioluminescence across the body when disturbed. This presumably serves to blind or distract the predator temporarily. Some jellyfish, ctenophores, and squid shed luminescing tentacles when attacked. A few squid and octopuses produce bioluminescent ink to dazzle and confuse attackers while they escape under cover. Some zooplankton-particularly copepods, ostracods, and shrimps-squirt a bioluminescent fluid as defense.

According to paragraph 5, in which of the following ways can bioluminescence function?

 

Factual Information Questions事实信息题

 

AAs a means of blinding or confusing a predator

BAs a means of poisoning or killed predators

CAs a way of making the body outline more distinct

DAs a way of attracting prey

8

In many parts of the ocean where bacteria and krill congregate in high densities to feed on suspended particulate material, their metabolic activities deplete the water of available oxygen, thereby creating the oxygen-minimum layer. Those organisms that exploit the detritus in this layer or feed on other organisms found there must cope with low oxygen levels. The fish, the krill, and the shrimp associated with this layer characteristically have large gills and blood that is highly efficient at absorbing any available oxygen. Typically, such animals are also sluggish and adopt an opportunistic policy rather than actively hunting for prey. This way, they conserve energy and reduce their oxygen requirement. Their skeleton and musculature are reduced, and their body shape and form is subordinated to the need to remain floating in the water column with the minimum of muscular effort.

Which of the following can be inferred from paragraph 6 about predators in the oxygen-minimum layer?

 

Inference Questions推理题

 

AThey are generaly stronger than predators in other parts of the ocean

BThey generally wait for their prey to come to them

CThey spend most of their time swimming around, searching for prey

DThey deplete less oxygen from the water than their prey do

9

Marine scientists identify several zones within the ocean’s vertical water column, from the sunlit surface to the deep, dark floor. [■] In the top layer, enough sunlight penetrates to allow photosynthesis and support a community of abundant life. [■] Below the sunlit zone is the mid-water level, called the mesopelagic zone, which receives only dim sunlight. [■] Fish and other creatures in the mesopelagic zone have adapted to low light and low oxygen levels.  [■]

Common adaptations among hunters in the mesopelagic zone are sensitive eyes and other light-detecting organs that perceive outlines and movement at low light levels. Typically, such devices are a hundred times more sensitive to light than human eyes. Predators and prey tend to adopt camouflage strategies that involve body transparency, color patterns and photophores (light-producing organs) that break up the body outline, or, as in the case of hatchet fishes, a body flattened from side to side to yield only a narrow silhouette when viewed from below.

Look at the four squares that indicate where the following sentence could be added to the passage

This level, sometimes referred to as the twilight zone, is not suitable for all aquatic organisms.Insert Text Questions句子插入题

Where would the sentence best fit？Click on a square  sentence to the passage.

10

Animals in the mesopelagic zone are adapted to conditions of low sunlight and relatively little oxygen.

 

Prose Summary Questions概要小结题

 

Select 3 answers

APredators often have extremely sensitive eyes or other light-detecting organs, and both predators and prey have developed body types or colors that serve to camouflage them in low light.

BBioluminescence can provide light for hunting, be used for communication, provide a means of defense, and help organisms blend into the background.

CIn areas where bacteria and krill gather in high densities to feed on particulate material, they provide food for copepods, ostracods, and other zooplankton.

DOrganisms in this zone produce light by means of a chemical reaction, which creates heat and, secondarily, light; the reaction is not possible without the presence of certain bacteria.

EFish, krill, and shrimp that feed in the oxygen-minimum layer have large gills, blood that is efficient at absorbing oxygen, and bodies that float without using much energy.

FZooplankton in upper, lighter levels of the mesopelagic zone are brighter colors, whereas in the deeper levels they tend to be black or grey to blend in to the background.