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BIOL 331
BIOL331 / BIOL 331 Module 3| Pathophysiology | (Latest
Update ) Questions & Answers | Grade A |
100% Correct - Portage Learning
1.
A nursing instructor is teaching about global ecosystems. The open ocean accounts for
approximately what percentage of the Earth's total primary productivity?
A. 25%
B. 50%
C. 75%
D. 90%
CORRECT ANSWER: C
Rationale: The vast area of the open ocean contributes about 75% of the planet's total
primary production, primarily through phytoplankton photosynthesis.
2.
In which latitude zone is primary productivity in the open ocean typically highest?
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A. Polar waters
B. Temperate waters
C. Tropical waters
D. Equatorial waters
CORRECT ANSWER: B
Rationale: Temperate ocean waters experience seasonal nutrient mixing (e.g., spring
blooms), leading to higher productivity compared to nutrient-poor tropical waters.
3.
Why are tropical open oceans generally less productive than temperate zones?
A. Higher predator density
B. Deeper pycnocline limiting nutrient upwelling
C. Excessive sunlight inhibiting growth
D. Lower water temperatures
CORRECT ANSWER: B
Rationale: The strong, shallow pycnocline (density gradient) in tropical waters restricts
vertical mixing, limiting the influx of nutrients from deeper waters to the sunlit surface
layer.
4.
In the open ocean, which trophic level typically has greater biomass?
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A. Primary consumers (zooplankton)
B. Producers (phytoplankton)
C. Top predators (nekton)
D. Decomposers
CORRECT ANSWER: B
Rationale: Due to overall low nutrient availability, open ocean ecosystems support a
larger biomass of producers relative to consumers, unlike coastal systems with higher
nutrient input.
5.
In temperate oceans, what is the primary factor causing seasonal fluctuations in primary
productivity?
A. Changes in predator populations
B. Variations in nutrient supply
C. Fluctuations in water salinity
D. Shifts in ocean currents
CORRECT ANSWER: B
Rationale: Seasonal changes in vertical mixing and sunlight drive the availability of
nutrients (e.g., nitrates, phosphates), which directly controls phytoplankton growth
cycles.
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6.
A spring phytoplankton bloom in temperate oceans is primarily caused by:
A. Increased water temperature and stratification
B. High solar energy and nutrient replenishment from winter mixing
C. Reduced grazing by zooplankton
D. Calmer sea conditions
CORRECT ANSWER: B
Rationale: Increased sunlight in spring, combined with nutrients brought to the surface
by winter wind-driven mixing, creates ideal conditions for a rapid increase in
phytoplankton.
7.
Primary productivity in temperate oceans declines during the summer due to:
A. Increased predation
B. Formation of a strong thermocline and nutrient depletion in surface waters
C. Excessive rainfall diluting nutrients
D. Decreased sunlight intensity
CORRECT ANSWER: B
Rationale: Summer stratification creates a strong thermocline that traps nutrients in
BIOL 331
BIOL 331
BIOL331 / BIOL 331 Module 3| Pathophysiology | (Latest
Update ) Questions & Answers | Grade A |
100% Correct - Portage Learning
1.
A nursing instructor is teaching about global ecosystems. The open ocean accounts for
approximately what percentage of the Earth's total primary productivity?
A. 25%
B. 50%
C. 75%
D. 90%
CORRECT ANSWER: C
Rationale: The vast area of the open ocean contributes about 75% of the planet's total
primary production, primarily through phytoplankton photosynthesis.
2.
In which latitude zone is primary productivity in the open ocean typically highest?
BIOL 331
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BIOL 331
A. Polar waters
B. Temperate waters
C. Tropical waters
D. Equatorial waters
CORRECT ANSWER: B
Rationale: Temperate ocean waters experience seasonal nutrient mixing (e.g., spring
blooms), leading to higher productivity compared to nutrient-poor tropical waters.
3.
Why are tropical open oceans generally less productive than temperate zones?
A. Higher predator density
B. Deeper pycnocline limiting nutrient upwelling
C. Excessive sunlight inhibiting growth
D. Lower water temperatures
CORRECT ANSWER: B
Rationale: The strong, shallow pycnocline (density gradient) in tropical waters restricts
vertical mixing, limiting the influx of nutrients from deeper waters to the sunlit surface
layer.
4.
In the open ocean, which trophic level typically has greater biomass?
BIOL 331
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BIOL 331
A. Primary consumers (zooplankton)
B. Producers (phytoplankton)
C. Top predators (nekton)
D. Decomposers
CORRECT ANSWER: B
Rationale: Due to overall low nutrient availability, open ocean ecosystems support a
larger biomass of producers relative to consumers, unlike coastal systems with higher
nutrient input.
5.
In temperate oceans, what is the primary factor causing seasonal fluctuations in primary
productivity?
A. Changes in predator populations
B. Variations in nutrient supply
C. Fluctuations in water salinity
D. Shifts in ocean currents
CORRECT ANSWER: B
Rationale: Seasonal changes in vertical mixing and sunlight drive the availability of
nutrients (e.g., nitrates, phosphates), which directly controls phytoplankton growth
cycles.
BIOL 331
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BIOL 331
6.
A spring phytoplankton bloom in temperate oceans is primarily caused by:
A. Increased water temperature and stratification
B. High solar energy and nutrient replenishment from winter mixing
C. Reduced grazing by zooplankton
D. Calmer sea conditions
CORRECT ANSWER: B
Rationale: Increased sunlight in spring, combined with nutrients brought to the surface
by winter wind-driven mixing, creates ideal conditions for a rapid increase in
phytoplankton.
7.
Primary productivity in temperate oceans declines during the summer due to:
A. Increased predation
B. Formation of a strong thermocline and nutrient depletion in surface waters
C. Excessive rainfall diluting nutrients
D. Decreased sunlight intensity
CORRECT ANSWER: B
Rationale: Summer stratification creates a strong thermocline that traps nutrients in
BIOL 331
