Chapter 6
Biomes
6-1 How are organisms on
Earth connected?
Connections in the Biosphere
 The
biosphere is the part of Earth in
which living things are found.
 All organisms share earth’s resources,
such as water, air, and light.
 The study of how living things interact
with each other and their environment is
called ecology.
Organization of the Biosphere
 An
environment includes both living and
nonliving parts.
 A population is a group of individuals
that belong to the same species and live
in the same area.
 Every member of a population needs
food, water, air, space, shelter, and
other resources.
 A community
is a group of populations
that interact with each other in a
particular area.
 An ecosystem is a community of
organisms living together along with the
nonliving parts of the environment.
 An ecosystem can be as small as a
crack in a sidewalk or as large as a
forest.
Meeting the Needs of
Organisms
 Abiotic
factors are the nonliving parts of
an ecosystem:
 Water
 Sunlight
 Temperature
 Soil
 Air

The amount of water in an ecosystem can
limit the number of organisms it can support.
 Since plants need sunlight for
photosynthesis, sunlight is important to all
living things.
 The amount of sunlight an area receives
determines the kind of plants that grow there.
 The temperature of an area also determines
what organisms live there.
 Biotic factors are the living organisms in an
ecosystem.
Adaptations
 Biotic
and abiotic factors shape the
communities that live in an ecosystem.
 All organisms in a particular ecosystem
have adaptations that help them survive
there.
 An adaptation is a characteristic that
helps an organism live and reproduce in
a particular environment.
Chapter 6 Lesson 2
What are Earth’s biomes?
Climate and Biomes
 Similar
communities occur in places that
have similar climates and landforms.
 A biome is a large group of ecosystems
with similar climates and organisms.
 Climate is the average yearly
temperature and precipitation in an
area.
 A tropical
rain forest has wet, humid
conditions and long periods of sunlight
that make it an ideal place for large
trees and other plants to grow.
 Trees block some sunlight and help
make different environments within the
rain forest.
 Scientists estimate that at least two
million species live in Earth’s rain
forests.
 Trees
do not grow in cold climates, but
you will find mosses and small shrubs.
 Grasslands bet about 60 cm of
precipitation a year. Therefore very few
trees grow there.
Characteristics of Biomes

Climate is an important factor in determining
which organisms can live in an area.
 Soil varies from place to place, and it plays an
important role in what kinds of plants can
survive in an ecosystem.
 Although similar biomes in different part of
earth will share similar climate and
organisms, there are differences.
Tropical Rain Forest
 The
tropical rain forest contain more
species than any other biome.
 More than half of the rain forests have
been destroyed.
Deciduous Forest

The most common plants are deciduous
trees.
 Deciduous trees shed their leaves each year
and then grow new ones.
 As the forest trees lose their leaves each
year, the fall to the ground and decay.
 The soil is nutrient rich in a deciduous forest
due to the decaying leaves that have fallen.
Taiga
 Conifers,
such a fir, spruce, and
hemlock, are some of the plants that
have adapted to the poor soil and long
cold winters of the taiga.
 The taiga is also called the boreal forest
or coniferous forest.
Grassland
 Grasslands
do not get enough rain to
have large trees growing in them.
 The grasslands has some of the most
fertile soil and is an excellent place for
farming.
 Some of the largest animal on Earth live
on grasslands including bison, zebras,
rhinoceros, and giraffes.
Tundra

The tundra has a permafrost which is a layer
of permanently frozen soil just beneath the
surface.
 The cold temperatures, high winds, and short
growing season limit plant growth to short
shrubs, grasses, mosses, and a few very
short trees.
 Foxes, lemmings, hares, and caribou are a
few of the common animals.
Desert
 All
desert are not hot. Many deserts
can be quite cool, especially at night.
 The characteristic that is common to all
deserts is that they are dry.
 Desert plants include cacti and other
plants that have short growth cycles.
 Many animals are active at night when
the temperatures are cooler.