BSC 2011 Exam 4 Learning Objectives | University of
South Florida | UPDATED Questions with 100% Verified
Answers
Q1: List biotic and abiotic factors that limit the distribution and
abundance of organisms, in both terrestrial and aquatic
ecosystems
A: Abiotic Factors: sunlight, temperature, rain, wind, soil, moisture levels, salinity, light, pH
Biotic Factors: predation, competition, parasitism, mutualism (producers, consumers,
decomposers)
Q2: Recognize that temperature and water levels are the abiotic
factors that most influence distribution of the major terrestrial
biomes, and describe how temperature and water levels vary
with latitude and topography
A: Temperature and water levels affect the distribution of the major terrestrial biomes the
most
Q3: Temperature
A: Temperature: most animals are ectotherms, meaning they get their metabolism from the
outside environment; organisms typically function best within a specific range of
environmental temperature
temperatures outside that range may force some animals fo expend energy regulating
their internal temperature (such as mammals and birds)
low temp: water freezes; free plants
high temp: denature proteins
Latitude: temperatures are typically warmer approaching the equator and cooler
approaching the poles
Driest area is 30 degrees north and south - more sunlight, less rainfall
Topography: Temperature decreases in height; highest temperatures at low altitudes and
lower temperatures at higher altitudes
Q4: How water influences the distribution of the major terrestrial
biomes
A: Water: if water levels are too low, species that live at the seashore or in tidal wetlands can
desiccate as the tide recedes
affects the ability to obtain and conserve water
organisms restricted to freshwater or saltwater habitats by limited ability for
osmoregulation
affects oxygen concentration; can limit cellular respiration and other physiological
processes
lack of water: desiccation
excess water: drowns plants and other organisms
, Q5: Describe how temperature limits the ranges of organisms at
different
time scales
A: Temperature: organisms typically function best within a specific range of environmental
temperature,
so temperatures that fall outside that range will force organisms to expend their energy
and limit their movement to areas that have their optimal temperature
Affects biological processes such as cellular respiration, enzymatic activity and CaCO3
precipation
Q6: Describe how water levels limit the range of organisms at
different time scales
A: Water: lack of water can cause desiccation in animals that depend on water for survival
and too much water can quickly drown the organisms
Oxygen: depends on the amount of water available in the aquatic environment; very low
in deep ocean ad deep lake waters where organic matter is abundant
Salinity: affects the water balance of organisms through osmosis; most organisms are
restricted to either freshwater or saltwater habitats by their limited ability to
osmoregulate
Q7: Describe how sunlight limits the ranges of organisms at
different time scales
A: Sunlight: provides energy that drives most of the ecosystem, and lack of sunlight can limit
the distribution of photosynthetic species;
too much light can limit survival by damaging DNA and proteins, can prevent trees from
surviving above a certain level
in aquatic systems, photosynthesis occurs only in the top of the water due to the
position of the sun
Q8: Describe how geographic barriers limit the ranges of
organisms at different time scales
A: Geographic disturbances limits movement
Barriers to dispersal affect ranges (continents or oceans could be in the way)
Distribution patterns are caused by current climate, evolutionary history and dispersal
Q9: Explain how global warming influences the distribution of
species
A: Increased production of CO2 increase Earth's temperature, which makes it difficult for
animals that live in cool environments to adapt
Increased CO2 causes a significant decrease in pH of oceans
Causes species to expand its climate change to adapt to the environment
Changes in global climate will likely occur too rapidly for normal evolutionary processes
to compensate
Some species face a shortage of suitable replacement habitat, while others cannot
migrate quickly enough, causing many species to decrease in size or disappear
South Florida | UPDATED Questions with 100% Verified
Answers
Q1: List biotic and abiotic factors that limit the distribution and
abundance of organisms, in both terrestrial and aquatic
ecosystems
A: Abiotic Factors: sunlight, temperature, rain, wind, soil, moisture levels, salinity, light, pH
Biotic Factors: predation, competition, parasitism, mutualism (producers, consumers,
decomposers)
Q2: Recognize that temperature and water levels are the abiotic
factors that most influence distribution of the major terrestrial
biomes, and describe how temperature and water levels vary
with latitude and topography
A: Temperature and water levels affect the distribution of the major terrestrial biomes the
most
Q3: Temperature
A: Temperature: most animals are ectotherms, meaning they get their metabolism from the
outside environment; organisms typically function best within a specific range of
environmental temperature
temperatures outside that range may force some animals fo expend energy regulating
their internal temperature (such as mammals and birds)
low temp: water freezes; free plants
high temp: denature proteins
Latitude: temperatures are typically warmer approaching the equator and cooler
approaching the poles
Driest area is 30 degrees north and south - more sunlight, less rainfall
Topography: Temperature decreases in height; highest temperatures at low altitudes and
lower temperatures at higher altitudes
Q4: How water influences the distribution of the major terrestrial
biomes
A: Water: if water levels are too low, species that live at the seashore or in tidal wetlands can
desiccate as the tide recedes
affects the ability to obtain and conserve water
organisms restricted to freshwater or saltwater habitats by limited ability for
osmoregulation
affects oxygen concentration; can limit cellular respiration and other physiological
processes
lack of water: desiccation
excess water: drowns plants and other organisms
, Q5: Describe how temperature limits the ranges of organisms at
different
time scales
A: Temperature: organisms typically function best within a specific range of environmental
temperature,
so temperatures that fall outside that range will force organisms to expend their energy
and limit their movement to areas that have their optimal temperature
Affects biological processes such as cellular respiration, enzymatic activity and CaCO3
precipation
Q6: Describe how water levels limit the range of organisms at
different time scales
A: Water: lack of water can cause desiccation in animals that depend on water for survival
and too much water can quickly drown the organisms
Oxygen: depends on the amount of water available in the aquatic environment; very low
in deep ocean ad deep lake waters where organic matter is abundant
Salinity: affects the water balance of organisms through osmosis; most organisms are
restricted to either freshwater or saltwater habitats by their limited ability to
osmoregulate
Q7: Describe how sunlight limits the ranges of organisms at
different time scales
A: Sunlight: provides energy that drives most of the ecosystem, and lack of sunlight can limit
the distribution of photosynthetic species;
too much light can limit survival by damaging DNA and proteins, can prevent trees from
surviving above a certain level
in aquatic systems, photosynthesis occurs only in the top of the water due to the
position of the sun
Q8: Describe how geographic barriers limit the ranges of
organisms at different time scales
A: Geographic disturbances limits movement
Barriers to dispersal affect ranges (continents or oceans could be in the way)
Distribution patterns are caused by current climate, evolutionary history and dispersal
Q9: Explain how global warming influences the distribution of
species
A: Increased production of CO2 increase Earth's temperature, which makes it difficult for
animals that live in cool environments to adapt
Increased CO2 causes a significant decrease in pH of oceans
Causes species to expand its climate change to adapt to the environment
Changes in global climate will likely occur too rapidly for normal evolutionary processes
to compensate
Some species face a shortage of suitable replacement habitat, while others cannot
migrate quickly enough, causing many species to decrease in size or disappear
