Transcript The Biosphere Powerpointx

Ecology
The Biosphere
3. 1 What is ecology?
• Ecology is the scientific study of interactions
among organisms and between organisms and
their physical environment.
• Levels of Organization:
1)individual organism (A species is a group of
similar organisms that can breed and produce
fertile offspring.) ex-zebra
2)population- a group of individuals that belong
to the same species and live in the same area;exgroup of zebras
Levels of Organization Continued
3)community- an assemblage of different
populations that live together in a defined area;
ex-group of zebras, group of lions, group of
elephants
4)ecosystem-all the organisms that live in a place,
together with their physical environment; excoral reef & all abiotic factors that affect it
5)biome-a group of ecosystems that share similar
climates & typical organisms;ex-tundra,
desert,etc.
Levels of Organization Continued
6)biosphere-all life on Earth and parts of the
Earth in which life exists, including land, water,
and the atmosphere
What are abiotic and biotic factor?
*abiotic factors-any nonliving part of the
environment, such as sunlight, heat,
precipitation, humidity, wind or water currents,
soil types, and so on.
*biotic factors-any living part of the environment
with which an organism might interact, including
animals, plants, mushrooms, and bacteria.
What Is abiotic and biotic?
What is grass? Clouds? Air? Trees? Wind?
3.2 Energy, Producers, & Consumers
• Autotrophs(producers)- organisms that make
their own food through photosynthesis or
chemosynthesis;ex-algae, certain bacteria,
and plants
• Heterotrophs(consumers)-organisms that rely
on other organisms for energy and nutrients
Types of Consumers
1)Carnivores-meat eaters; ex-snake, frog, fox
Types of Consumers Continued
2)Herbivores-plant eaters; ex-cow, deer
3)Omnivores-eat both plant & animal; exbears,pigs
4)Scavengers-animals that eat the carcasses of
other animals that have been killed by
predators or other causes; ex-vulture
5)Decomposers-organisms that feed by
chemically breaking down organic matter; exbacteria & fungi(like mushrooms)
Types of Consumers Continued
6)Detritivores-organisms that commonly digest
decomposers that live on, and in, detritus
particles;ex-earthworms, mites, snails, shrimp,
and crabs
*primary producers-the 1st producers of energy-rich
compounds that are later used by other
organisms
*photosynthesis-captures light energy & uses it to
power chemical reactions that convert carbon
dioxide & water into oxygen & carbohydrates
Processes That Involve Energy
*chemosynthesis-process in which chemical energy
is used to produce carbohydrates; takes place in
deep-sea volcanic vents, hot springs, and tidal
marshes along the coast
3.3 Energy Flow in Ecosystems
How does energy flow through ecosystems?
Energy flows through an ecosystem in a one-way
stream, from primary producers to various
consumers
Food Chain
Food chain-a series of steps in which organisms
transfer energy by eating and being eaten.
Trophic level-each step in a food chain or food web
Food Web
• Food web-network of complex interactions
formed by the feeding relationships among
the various organisms in an ecosystem
Food Web
Energy pyramid
Pyramids of energy show the relative amount of energy
available at each trophic level of a food chain or food web.
The 10% Rule
How much energy is lost from one trophic level to
the next on an energy pyramid? Scientists say
that on average 90% of the available energy is
used for life processes such as respiration,
photosynthesis, reproduction, and transformed
to heat energy before an organism is consumed.
This means only about 10% of the original energy
is left to feed the next level. This 10% is stored in
the tissues(leaves, stems, muscles, organs, fat,
etc.) of the organism.
3.4 Cycles of Matter
• Water Cycle
Step 1: A large quantity of water evaporates from
the surface of the ocean. Evaporation is the
conversion of liquid water to a gaseous form of
water called water vapor.
Step 2: The water vapor then condensed to form
clouds. Most of this condensed water will then
precipitate back into the ocean, but some will
travel on & eventually float over land.
Precipitation means to condense from a vapor &
fall as rain or snow.
Water Cycle Continued
Step 3: The condensed water (clouds) that floats
over land picks up more water vapor from
evaporation & transpiration. Transpiration is the
evaporation of water from leaves of plants.
Step 4: The accumulated water vapor will then
fall to the ground as rain.
Step 5: The rain water makes its way back to the
ocean through streams & rivers & starts the cycle
all over again
Carbon Cycle
Step 1: Carbon enters the atmosphere as carbon
dioxide from respiration(breathing) & combustion
(burning).
Step 2: Carbon dioxide is absorbed by producers to
make carbohydrates in photosynthesis. These
producers then put off oxygen.
Step 3: Animals feed on the plants. Thus passing the
carbon compounds along the food chain. Most of the
carbon these animals consume however is exhaled as
carbon dioxide. This is through the process of
respiration. The animals & plants then eventually die.
Carbon Cycle Continued
Step 4: The dead organisms (dead animals &
plants) are eaten by decomposers in the
ground. The carbon that was in their bodies is
then returned to the atmosphere as carbon
dioxide. In some circumstances the process of
decomposition is prevented. The decomposed
plants & animals may then be available as
fossil fuel in the future for combustion.
The Nitrogen Cycle
Step 1: A special type of bacteria called
nitrogen fixing bacteria take in atmospheric
nitrogen and produce ammonia.
Step 2: Other bacteria use this ammonia to
produce nitrates & nitrites, which are nitrogen
and oxygen containing compounds.
Step 3: The nitrates & nitrites are used by plants
to make amino acids which are then used to
make plant proteins.
Nitrogen Cycle Continued
Step 4: Plants are consumed by other
organisms which use the plant amino acids to
make their own.
Step 5: Decomposers convert the nitrogen
found in other organisms into ammonia and
return it to the soil. A few of these types of
bacteria return nitrogen back to the
atmosphere by a process called denitrification,
however this amount is small.
Phosphorus Cycle
Step 1: Over time, rain and weathering cause rocks to
release phosphate ions & other minerals. This inorganic
phosphate is then distributed in soils & water.
Step 2: Plants take up inorganic phosphate from the soil.
The plants may then be consumed by animals. Once in the
plant or animal, the phosphate is incorporated into organic
molecules such as DNA. When the plant or animal dies, it
decays, and the organic phosphate is returned to the soil.
Step 3: Within the soil, organic forms of phosphate can be
made available to plants by bacteria that break down
organic matter to inorganic forms of phosphorus. This
process is called mineralization.
Phosphorus Cycle Continued
Step 4: Phosphorus in the soil can end up in
waterways & eventually oceans. Once there, it
can be incorporated into sediments over time.