ECOSYSTEMS

AND THE

BIOSPHERE

CHAPTERS

18.3/18.4/21 NOTES

VOCABULARY WORDS- words

Producers biogeochemical cycle

Chemosynthesis groundwater permafrost

Gross primary productivity tropical forest

Biomass water cycle tundra

Net primary productivity transpiration canopy

Consumer carbon cycle epiphyte

Herbivore nitrogen cycle coniferous tree

Carnivore nitrogen fixation deciduous tree

Omnivore nitrogen-fixing bacteria

Detritivore ammonification taiga

Decomposer nitrification savanna

Trophic level denitrification chaparral

Food chain phosphorus cycle desert

Food web biome temperate grassland

Temperate deciduous forest

I. Producers

A. Autotrophs produce their own food

1. Photosynthesis: Plants, Protists, Bacteria

2. Chemosynthesis: Bacteria

B. Carbohydrates (sugars and starches) are produced as food

C. Gross Primary Productivity: the rate at which producers in an ecosystem capture energy

D. Biomass is the organic material found in

an ecosystem

E. Net Primary Productivity is the rate at

which biomass accumulates.

F. Ecosystem vary in productivity

1. Light, temperature, and precipitation affect

terrestrial ecosystems

2. Light and available nutrients affect aquatic

ecosystems

II. Consumers

A. Heterotrophs obtain energy by feeding on other organisms or their waste products.

B. Herbivores eat producers.

C. Carnivores eat other consumers.

D. Omnivores eat producers and consumers.

E. Detritivores eat rotting carcasses, fallen leaves and branches (detritus).

F. Decomposers obtain energy by breaking down complex molecules into simpler ones.

III. Energy Flow

A. Trophic levels indicates organisms’

positions in sequences of energy transfers.

B. A food chain is a single pathway of

feeding relationships.

C. A food web is

composed of

interrelated food

chains.

D. 10% of energy from one trophic level is

available for the next trophic level.

E. There are more

organisms in lower

trophic levels than

in higher ones.

IV. The water cycle

A. Evaporation adds water to the atmosphere.

B. Transpiration is when plants release water

vapor.

C. Precipitation is the release of water from the

atmosphere.

V. The carbon cycle

A. Photosynthesis and cellular respiration are the

basis of this cycle.

B. Humans add much carbon dioxide to the air.

VI. The nitrogen cycle

A. Proteins and nucleic acids use nitrogen.

B. Nitrogen fixation is the conversion of

nitrogen gas to ammonia, nitrites, and

nitrates.

1. This is nitrification and is accomplished by

aerobic nitrogen-fixing bacteria.

C. Ammonification is the release of ammonia

from dead organisms and waste products.

1. This provides nitrogen for living organisms.

D. Denitrification is the release of nitrogen

gas back into the air by anaerobic bacteria.

VII. Phosphorus Cycle

A. Phosphate (PO4-3) erodes from rocks into

the soil. Plants absorb phosphorus atoms

from the soil.

B. Animals get phosphorus atoms by eating

plants and other animals.

C. DNA and RNA use phosphorus atoms in

part of their make-up, so do teeth and

bones.

VII. The seven major biomes

A. Biomes: very large terrestrial ecosystems

that contain a number of smaller but

related ecosystems within them.

B. Temperature and precipitation distinguish

the biome.

C. Plants and animals are unique to each

biome.

D. Tundra

E. Taiga

F. Temperate Deciduous Forests

G. Temperate Grasslands

H. Deserts

I. Savannas

J. Tropical Rain Forests

VIII. Aquatic Ecosystems

A. Ocean Zones

1. Intertidal zone

2. Neritic zone

3. The Oceanic zone

4. Estuaries

B. Freshwater Zones