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UNIT 5

Chapter 15 The Biosphere

UNIT 5: ECOLOGY

Chapter 15: The Biosphere

I. Life in the Earth System (15.1)

A. The biosphere is the portion of the Earth

that is inhabited by life

1. Biosphere- part of Earth where life

exists

a. Includes all living and non-

living parts

b. Biota- collection of just

living things in biosphere

a. Includes all living and non-living parts

b. Biota- collection of just living things in biosphere

2. Earth has 4 major connected systems

a. Biosphere

b. Hydrosphere- all of Earth’s water, ice,

water vapor

c. Atmosphere- the air

blanketing Earth’s solid

and liquid surface

d. Geosphere- features

of Earth’s surface

(continents, rocks, sea

floor, and everything

below Earth’s surface

B. Biotic and Abiotic factors interact in the

biosphere

1. All four of Earth’s

systems are

connected to

another

2. Gaia

hypothesis- Earth

itself is kind of a

“living organism”

II. Climate (15.2)

A. Climate is the prevailing weather of a

region

1. Weather- day to day conditions

2. Climate- long term pattern of

weather conditions

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2. Climate- long term pattern of weather conditions

B. Key factors that shape an area’s climate

1. temperature- key

factor

2. sunlight

3. water (moisture)-

key factor

4. wind

C. Microclimate- climate of a small specific place

within larger area.

1. Can be very important to living things

2. Can be very small or large area

D. Earth has three main climate zones

1. Use average temperature and

precipitation to categorize

a. Polar zone -in far

northern and southern

regions

b. Tropical zone-

surrounds the equator

c. Temperate zone- wide

area between polar and

tropical zones

2. Influence of sunlight

a. Earth’s surface heated unevenly

1). Hottest portion where sun strikes

directly

2). Curved shape causes uneven heating

3). Earth tilts on its axis and this also plays a role

in seasonal changes

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3. Air and Water Movement

a. Sun also warms water and air

b. Uneven heating causes wind and water

currents

c. Warm air (and water) rises

and cold air (and water) sinks

d. Also affects amount of

precipitation (warm air holds

more water than cold air)

4. Landmasses- also shape climate

a. Coastal areas tend to have smaller

changes in temperature (moderated by

oceans)

b. Mountains have large effect on climate-

causes precipitation

western slope eastern slope

5. Adaptation to Climate- Many organisms adapted

to survive in specific climate

III. Biomes (15.3)

A. Earth has 6 major biomes- Each biome

characterized by certain set of abiotic

factors, ecosystems

1. Tropical Rain Forest

Biome- warm temperatures,

abundant precipitation all

year, lush forests

Source: World Meteorological Organization

2. Grassland Biome-

primary plant life is

grass. Occurs in variety

of climates

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3. Desert Biome- arid

environment, little

precipitation, four types: hot,

semi-arid, coastal, and cold

4. Temperate Forests-

Include deciduous forests

and rain forests. Temperate

deciduous forests have hot

summers and cold winters.

Deciduous trees are the

dominant plant species

5. Taiga- Found in cool

northern climates. Long

winters, short summers. Small

amount of precipitation

6. Tundra- Far northern

latitudes with long winters (10

months) limited precipitation,

permafrost

7. Minor biomes- example: chaparral- hot, dry

summers and cool, moist winters

B. Polar ice caps and mountains are not

considered biomes

1. Polar ice caps- have no soil and do not

have specific plant community

a. Found at poles

(north and south)

b. Most animals

depend on sea for food

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IV. Marine Ecosystems (15.4)

A. The ocean can be divided into zones

1. Ocean Zones

a. Divided into open sea (pelagic) and ocean floor

(benthic zone)

b. Divided between areas that receive light (photic

zone) and those that do not (aphotic zone)

photic zone

aphotic zone

c. Ocean also separated into zones using distance

from shoreline and water depth

1). Intertidal zone- between high and low

tide lines

2). Neritic zone-extends from intertidal out to edge

of continental shelf

3). Bathyal zone- extends from edge of neritic

zone to base of continental shelf

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4). Abyssal zone- lies below 2000 meters and is in

complete darkness

d. Life in Neritic Zone- only 1/10th of ocean but

contains majority of biomass (Most biomass

consists of plankton)

B. Coastal waters contain unique habitats

1. Coral Reefs- found within tropical zone

and contains large diversity

2. Kelp Forests- found in cold, nutrient rich waters

V. Estuaries and Freshwater Ecosystems (15.5)

A. Estuaries are dynamic environments

where rivers flow into the ocean

1. Estuary- partially enclosed body of

water formed where a river flows into

the ocean

a. Mix of fresh and salt water

b. River carries lots of nutrients

c. Large numbers of species thrive and are highly

productive ecosystems

d. Provide refuge for many species and spawning

grounds

e. Over 80% of

estuaries have been

lost to land

development

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B. Freshwater ecosystems include moving and

standing water

1. Freshwater ecosystems- rivers, streams,

wetlands

2. among most

productive

ecosystems on

Earth

C. Ponds and lakes share common features

1. Smaller in size than oceans, but also

divided into zones

a. Littoral zone- between low and high water

marks

b. Limnetic zone- open water farther out from

shore

c. Benthic zone- bottom of lake or pond where

less sunlight reaches

Chapter 15

The Biosphere

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The average year-after-year conditions of

temperature and precipitation in a particular region is

the region’s

a. weather.

b. latitude.

c. ecosystem.

d. climate.

The Earth’s climate is, in part, created by the

interplay of

a. temperatures, ecosystems, and wind.

b. landmasses, the atmosphere, and the ocean.

c. weather, heat transport, and the environment.

d. solar radiation, surface temperatures, and

biomes.

The loss of heat to space is slowed by

a. radiation entering the atmosphere.

b. atmospheric gases.

c. solar energy.

d. the biosphere.

The greenhouse effect is

a. the result of an excess of carbon dioxide in the

atmosphere.

b. a natural phenomenon that maintains Earth’s

temperature range.

c. the result of the differences in the angle of the

sun’s rays.

d. an unnatural phenomenon that causes heat

energy to be radiated back into the atmosphere.

Earth has three main climate zones because of the

differences in latitude and

a. amount of solar energy received.

b. angle of heating.

c. ocean currents.

d. prevailing winds.

Cool air over the poles will

a. rise.

b. sink.

c. absorb heat from the equator.

d. flow parallel to Earth’s surface.

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Each of the following is an abiotic factor in the

environment EXCEPT

a. plant life.

b. soil type.

c. rainfall.

d. temperature.

Which is a biotic factor that affects the size of a

population in a specific ecosystem?

a. average temperature of the ecosystem

b. type of soil in the ecosystem

c. number and kinds of predators in the

ecosystem

d. concentration of oxygen in the ecosystem

An organism’s niche is

a. the way the organism uses the range of

physical and biological conditions in which it lives.

b. all the physical and biological factors in the

organism’s environment.

c. the range of temperatures that the organism

needs to survive.

d. a full description of the place an organism

lives.

Several species of warblers can live in the same

spruce tree ONLY because they

a. have different habitats within the tree.

b. eat different foods within the tree.

c. occupy different niches within the tree.

d. can find different temperatures within the tree.

An interaction in which one organism captures and

feeds on another organism is called

a. competition.

b. sybiosis.

c. mutualism.

d. predation.

Different species can share the same habitat, but

competition among them is reduced if they

a. reproduce at different times.

b. eat less.

c. move away.

d. occupy different niches.

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No two species can occupy the same niche in the

same habitat at the same time

a. because of the interactions that shape the

ecosystem.

b. unless the species require different abiotic

factors.

c. because of the competitive exclusion principle.

d. unless the species require different biotic

factors.

A symbiosis in which both species benefit is

a. commensalism.

b. mutualism.

c. predation.

d. parasitism.

The symbiotic relationship between a flower and the

insect that feeds on its nectar is an example of

a. mutualism because the flower provides the

insect with food, and the insect pollinates the flower.

b. parasitism because the insect lives off the

nectar from the flower.

c. commensalism because the insect doesn’t

harm the flower and the flower doesn’t benefit from

the relationship.

d. predation because the insect feeds on the

flower.

The series of predictable changes that occurs in a

community over time is called

a. population growth.

b. ecological succession.

c. climax community.

d. climate change.

Primary succession can begin after

a. a forest fire.

b. a lava flow.

c. farm land is abandoned.

d. a severe storm.

Which of the following occurs during the ecological

succession of an ecosystem?

a. An ecosystem reaches a final, unchanging

stage.

b. Changes occur that are caused by organisms

outside the ecosystem.

c. Living organisms modify their environment a

little at a time.

d. Parts of communities split off to form new

communities.

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Which biome is characterized by very low

temperatures, little precipitation, and permafrost?

a. desert

b. temperate forest

c. tundra

d. tropical dry forest

A biome is identified by its particular set of abiotic

factors and its

a. average precipitation and temperature.

b. characteristic ecological community.

c. distance from the equator.

d. specific geographical location.

Which is NOT an adaptation that organisms have for

living in flowing water?

a. hooks

b. plankton

c. streamlined bodies

d. suckers

The photic zone

a. extends to the bottom of the open ocean.

b. extends to a depth of about 200 meters.

c. is deep, cold, and permanently dark.

d. is where chemosynthetic bacteria are the

producers.

Which organism lives where it is routinely exposed

to air, heat, battering waves, strong currents, and is

often submerged?

a. sea stars

b. tube worms

c. dolphins

d. whales

In the food web below, which of the organixms, X, Y,

or Z, is a herbivore?

a. Z c. Both X and Y

b. Y d. X

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The picture above represents _________.

a. ecological evolution c. ecological growth

b. ecological succession d. ecological symbiosis

The climate diagram below probably illustrates which

of the following major biomes.

a. desert c. temperate forest

b. tropical savanna d. tropical rain forest