Chapter 42 Unit Questions
1. What is the difference between biotic and abiotic factors in an ecosystem? Provide some
examples.

Abiotic factors are nonliving components of the external environment, while biotic
factors are living components. Abiotic factors may include hills and rocks, whereas
biotic factors may include plants and animals in a specific environment.
2. What is the difference between weather and climate?

Weather is the condition of the atmosphere in a certain place at a certain time,
whereas climate is their average state and pattern over a longer period.
3. Describe how latitude differences affect solar energy, weather, and climate, and leads to
seasonality.

Latitude differences in solar energy are caused by differences in the angles of the
sun’s incoming rays; they drive north-south patterns of atmospheric circulation. These
patterns then influence weather and climate by influencing precipitation patterns.
Seasonality is resultant from the tilt of Earth’s axis of rotation.
4. Explain the relationship between atmospheric circulation and oceanic circulation and how each
affects an area’s climate.

Atmospheric circulation’s winds drive oceanic circulation’s winds. Because water has a
high heat capacity, atmospheric circulation affects its climate slowly; it does, however,
heavily affect land’s climate.
5. Define biome, and briefly describe the nine major terrestrial biomes, giving attention to the
climate, soil, and characteristic plants and animals of each.

A biome is “a distinct physical environment that is inhabited by ecologically similar
organisms with similar adaptations.” Species in a biome often show convergent
adaptations.

Savanna
i. Warmer climate with wet and dry seasons; home to grazing animals (zebras,
antelopes) as well as cheetahs and hyenas. Many types of grasses, some of
which include Bermuda grass and lemon grass. Porous soil that rapidly drains
water.

Tropical Rainforest
i. Warm climate year round, due to proximity to the equator; animals may
include monkeys, birds, snakes, and bats. Plants may include orchids and
bromeliads; great diversity of plants and animals exist. Soils vary greatly, but
most lose water easily and contain few nutrients.

Desert
i. Weather is generally hot during the day and cold at night; less than 30
centimeters of rain per year. Many types of cacti are common of deserts, as
well as desert animals such as kangaroo rats. Soils are usually dry and devoid
of much organic matter.

Coniferous Forest
i. Towering evergreen trees characterize this biome, including pine, spruce, and
fir; mainly temperate climate, but northern regions of this biome (taiga) often
have long, cold winters with heavy snowfall. Typical animals include hares,
moose, elk, wolves, and bears. Soils are acidic in nature, but low in mineral
content and organic material.

Temperate Deciduous Forest
i. Deciduous trees such as maple, oak, and hickory characterize this biome.
Animals found here may include squirrels, chipmunks, and foxes. Has a
temperate climate that goes through four seasons; soil is very fertile.

Grassland
i. Temperate climate; animals present in North American grasslands may include
bison and pronghorns. Dominated by many types of grasses, including purple
needlegrass and foxtail. Nutrient rich-soils are abundant here.

Chaparral
i. A temperate coastal biome that has a climate of rainy winters and hot, dry
summers; many dense evergreen shrubs likely present. Animals present may
include deer, birds, and rodents, as well as lizards and snakes. Nutrient poor
soil vulnerable to erosion.

Polar Ice
i. Freezing climate year round; animals present may include arctic wolves, polar
bears, and beluga whales. Vegetation may include wildflowers and arctic
poppies. Soil forms slowly and is usually frozen.

Tundra
i. Mosses, lichens, and grasses are often present, and large plants are rare. Very
cold climate; animals may include the arctic fox and caribou. Soil is low in
nutrients and minerals, and often frozen.
6. Desribe at least one human effect on each of the biomes discussed.

Savanna
i. Humans are lessening the space of savannas in order to make more space for
industrialization.

Tropical Rainforest
i. Humans rely on tropical rainforest trees for many paper, and have thus cut
down thousands upon thousands of them.

Desert
i. Humans often go off-roading and use the desert for recreational reasons; this
damages desert vegetation and soil.

Coniferous Forest
i. Humans have extensively harvested trees from coniferous forests, which is
making them smaller.

Temperate Deciduous Forest
i. Humans have harvested trees in these forests for use of timber and charcoal.

Grassland
i. Humans are dividing them up for farming and urban development; grasslands
are therefore also becoming smaller.

Chaparral
i. Humans cause more forest fires than natural in this biome, which is destroying
plants and vegetation.

Polar Ice
i. Humans have overfished in this biome, leading to extinctions of species. This
has also negatively impacted the food web.

Tundra
i. The effects of industrialization have led to global warming and the tundra’s
climate is thereby affected.
7. Create a table of biomes and for each biome, compare and contrast the characteristics of each
including locations, climate, fauna, temperature, rainfall, flora, and specific attributes.
Biome
Rainfall
(per
year)
Average
Temperature and
Climate
Locations
Flora
Fauna
Savanna
20-50 in
68° to 86° F; wet
and dry seasons
Near equator;
cover much of
Africa
Various grasses
Grazing animals,
cheetahs, hyenas
Desert
Less than
10 in
20-25° C; hot days,
cold nights; dry
Parts of Mexico,
Africa, South
America
Fewer plants;
cacti
Desert animals
like kangaroo
rats
Tundra
6-10 in
-34°C; Cold
Near North Pole
Mosses, lichens,
grasses, but
sparse
Arctic fox,
caribou
Coniferous
Forest
10-30 in
-40°C to 20°C;
temperate climate,
long, cold winters
Many near high
mountains
Evergreen trees
Hares, moose,
elk, wolves
Temperate
Deciduous
30-60 in
50°F; mild,
temperate climate
East U.S.;
Squirrels,
Deciduous trees
Canada, Europe,
chipmunks, foxes
Forest
Russia, China,
Japan
Grassland
20-35 in
Hot summers, cool
winters, very
variable temps
Tropical
Rainforest
50-260 in
68-93°F; warm and
wet
Polar Ice
Chaparral
Less than Less than 10°C; very
10 in
cold
10 to 17
in
64°F; rainy winters,
dry, hot summers
Africa, South
America, Eurasia, Various grasses
North America
Bison,
pronghorns
Near equator
Great diversity
of plants
Monkeys, birds,
snakes, bats;
great diversity
Greenland,
Antarctica
Few plants;
wildflowers,
arctic poppies
Polar bear, arctic
fox
Coasts of most
continents
Dense
evergreen
shrubs
Deer, birds,
rodents, lizards,
snakes
8. Explain the important environmental factors that affect aquatic ecosystems.

Aquatic ecosystems are affected and distinguished by water depth and movement,
temperature, pressure, and salinity. The primary distinction is salinity, which
distinguishes freshwater, saltwater, and estuarine biomes. Freshwater biomes can be
characterized by water movement, and still water biomes can be divided into water
depth zones.