Question 1

Why do sharks retain urea rather than excrete it? How does this influence their fitness?

Accepted Answer

Because the urea acts as a solute in their blood, it reduces the osmotic pressure produced by hyposmotic conditions in the ocean. Their fitness is improved because they require less energy to survive and therefore need less food to remain healthy.

Question 2

Why are both carbon dioxide and oxygen limited in aquatic environments?

Accepted Answer

A)  They are not very soluble. 
B)  They change to different chemical forms in water. 
C)  They cannot diffuse across cell membranes. 
D)  They are rare in the atmosphere and therefore limited in water. 
A)  They are not very soluble. 
B)  They change to different chemical forms in water. 
C)  They cannot diffuse across cell membranes. 
D)  They are rare in the atmosphere and therefore limited in water. A

Question 3

What concept does the nearby graph illustrate? Explain why it is important.

Accepted Answer

This illustrates the Q₁₀ ratio of physiological processes. This is a measure of how organisms increase their metabolism at higher temperatures and as a result develop faster, up to the point when high temperatures begin to have negative effects.

Question 4

Nine ponds are sampled, and the mean salt concentration is 121 ppm, with a sample variance of 25 ppm. What is the standard deviation of the sample?

Accepted Answer

A)  0.6 
B)  2.2 
C)  3 
D)  5 
E)  11 
A)  0.6 
B)  2.2 
C)  3 
D)  5 
E)  11

Question 5

The use of salt on roads in winter has led to

Accepted Answer

A)  adaptation of roadside plants to increased salt levels. 
B)  decreased survival of freshwater organisms in nearby ponds. 
C)  hyperosmotic conditions. 
D)  increased acid deposition. 
A)  adaptation of roadside plants to increased salt levels. 
B)  decreased survival of freshwater organisms in nearby ponds. 
C)  hyperosmotic conditions. 
D)  increased acid deposition.

Question 6

Which is used to increase oxygen extraction?

Accepted Answer

A)  hydrogen ions 
B)  boundary layers 
C)  countercurrent circulation 
D)  concurrent circulation 
A)  hydrogen ions 
B)  boundary layers 
C)  countercurrent circulation 
D)  concurrent circulation

Question 7

The low density of ice

Accepted Answer

A)  makes it ineffective at insulating water from the cold. 
B)  allows aquatic plants to survive the winter. 
C)  is due to the high viscosity of water. 
D)  prevents it from moving in water. 
A)  makes it ineffective at insulating water from the cold. 
B)  allows aquatic plants to survive the winter. 
C)  is due to the high viscosity of water. 
D)  prevents it from moving in water.

Question 8

Which part of an organism is less dense than water?

Accepted Answer

A)  bone 
B)  protein 
C)  muscle 
D)  fat 
A)  bone 
B)  protein 
C)  muscle 
D)  fat

Question 9

Why is it surprising that some organisms are able to live at temperatures above 75ºC?

Accepted Answer

A)  High temperatures decrease the efficiency of glycoproteins. 
B)  High temperatures denature proteins. 
C)  High temperatures evaporate water in cells. 
D)  High temperatures increase the permeability of cell membranes. 
A)  High temperatures decrease the efficiency of glycoproteins. 
B)  High temperatures denature proteins. 
C)  High temperatures evaporate water in cells. 
D)  High temperatures increase the permeability of cell membranes.

Question 10

Explain why freshwater fish do not need to drink water.

Accepted Answer

Since freshwater fish are hyperosmotic i

Question 11

In which location would you expect to find the highest levels of dissolved oxygen?

Accepted Answer

A)  deep ocean water 
B)  a freshwater bog 
C)  a landlocked lake 
D)  a fast, shallow river 
A)  deep ocean water 
B)  a freshwater bog 
C)  a landlocked lake 
D)  a fast, shallow river

Question 12

Which is NOT an adaptation that exploits the density of water?

Accepted Answer

A)  a gas-filled swim bladder 
B)  droplets of oil on algae 
C)  long, filamentous appendages 
D)  high percentages of fat 
A)  a gas-filled swim bladder 
B)  droplets of oil on algae 
C)  long, filamentous appendages 
D)  high percentages of fat

Question 13

The limit to the amount of minerals water can hold is called

Accepted Answer

A)  the dissolution limit. 
B)  the solvent point. 
C)  deposition. 
D)  saturation. 
A)  the dissolution limit. 
B)  the solvent point. 
C)  deposition. 
D)  saturation.

Question 14

A freshwater fish with a high concentration of dissolved nutrients will

Accepted Answer

A)  have high osmotic pressure. 
B)  have low osmotic pressure. 
C)  be hyposmotic. 
D)  actively secrete solutes. 
A)  have high osmotic pressure. 
B)  have low osmotic pressure. 
C)  be hyposmotic. 
D)  actively secrete solutes.

Question 15

Explain why thermal pollution is relatively rare in oceans.

Accepted Answer

Although local temperatures can be incre

Question 16

Which is NOT an adaptation to low-oxygen aquatic environments?

Accepted Answer

A)  increased hemoglobin 
B)  breathing air 
C)  increased metabolic activity 
D)  symbiotic relationship with algae 
A)  increased hemoglobin 
B)  breathing air 
C)  increased metabolic activity 
D)  symbiotic relationship with algae

Question 17

Explain why there are relatively few plant species in mangrove forests.

Accepted Answer

Mangrove forests have both low levels of

Question 18

What unique low-temperature challenge are marine organisms likely to encounter?

Accepted Answer

Because of its high salt content, seawat

Question 19

What enable thermophilic bacteria to withstand very high temperatures?

Accepted Answer

A)  high glycerol concentrations that protect cell membranes 
B)  low concentrations of isozymes that change form at high temperatures 
C)  cell materials that reduce heat transfer 
D)  high proportions of particular amino acids that form strong bonds 
A)  high glycerol concentrations that protect cell membranes 
B)  low concentrations of isozymes that change form at high temperatures 
C)  cell materials that reduce heat transfer 
D)  high proportions of particular amino acids that form strong bonds

Question 20

Which is the most basic?

Accepted Answer

A)  human blood 
B)  acid rain 
C)  carbonated beverages 
D)  pure water 
A)  human blood 
B)  acid rain 
C)  carbonated beverages 
D)  pure water

Exam 2: Adaptations to Aquatic Environments

Why do sharks retain urea rather than excrete it? How does this influence their fitness?

Why are both carbon dioxide and oxygen limited in aquatic environments?

What concept does the nearby graph illustrate? Explain why it is important.

Nine ponds are sampled, and the mean salt concentration is 121 ppm, with a sample variance of 25 ppm. What is the standard deviation of the sample?

The use of salt on roads in winter has led to

Which is used to increase oxygen extraction?

The low density of ice

Which part of an organism is less dense than water?

Why is it surprising that some organisms are able to live at temperatures above 75ºC?

Explain why freshwater fish do not need to drink water.

In which location would you expect to find the highest levels of dissolved oxygen?

Which is NOT an adaptation that exploits the density of water?

The limit to the amount of minerals water can hold is called

A freshwater fish with a high concentration of dissolved nutrients will

Explain why thermal pollution is relatively rare in oceans.

Which is NOT an adaptation to low-oxygen aquatic environments?

Explain why there are relatively few plant species in mangrove forests.

What unique low-temperature challenge are marine organisms likely to encounter?

What enable thermophilic bacteria to withstand very high temperatures?

Which is the most basic?

Introduction: Ecology, Evolution, and the Scientific Method

Adaptations to Terrestrial Environments

Adaptations to Variable Environments

Climates and Soils

Terrestrial and Aquatic Biomes

Evolution and Adaptation

Life Histories

Reproductive Strategies

Social Behaviours

Population Distributions

Population Growth and Regulation

Population Dynamics Over Space and Time

Predation and Herbivory

Parasitism and Infectious Diseases

Competition

Community Structure

Community Succession

Movement of Energy in Ecosystems

Movement of Elements in Ecosystems

Landscape Ecology, Biogeography, and Global Biodiversity

Global Conservation of Biodiversity

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