Transcript Ecosystems and Energy

Life on Earth depends on three
interconnected factors:
 The one-way flow of high quality energy
sun
living things (feeding interactions)
environment (low quality energy)
back
into space as (infrared radiation - heat).
 Cycling of matter or nutrients through parts of the
biosphere.
 Gravity which allows the planet to hold on to its
atmosphere and causes the downward movement
of chemical in the matter cycles.
Vocabulary to begin..
 Abiotic – non-living
 Biotic – living
More Vocabulary…
 Levels of biological
organization to know:
 Organism
 Population
 Community
 Ecosystem
 Biosphere
Earth’s Four Realms
 Hydrosphere – Earth’s supply of water
liquid and frozen, fresh and salty
 Atmosphere – gaseous envelope
surrounding the earth
 Lithosphere – soil and rock of Earth’s
crust
 Biosphere – all living organisms
Let’s Practice
What is the word for…
 A group of individuals of the same species
that occupy a common area.
 The unique environment that organisms are
best adapted to energy resources.
 One individual living thing.
 Where an organism lives.
 A group of organisms that are able to
produce fertile offspring.
Let’s Practice
What is the word for…
 A physically distinct, self-supporting unit of
interacting organisms and their
environment.
 Means living.
 A group of interacting populations of
different species
 Means non-living.
Energy Quality is..
The measure of an energy sources’ ability
to do useful work
 Entropy: a measure of disorder or
randomness of a system
Types of Energy Quality
 High quality: organized or concentrated and
can perform much useful work.
 Examples…
electricity nuclear energy solar energy
Types of Energy Quality
 Low quality: disorganized or dispersed
and has little ability to do useful work.
 Example…
heat in
the ocean
Closed vs. Open System
 The earth is an open system for energy. We
receive energy from the sun and heat energy
is released back into the universe. We
exchange energy with our surroundings.
 The earth is a closed system for matter.
Matter is never created or destroyed. All
matter that is here has always been here.
Are you breathing the same oxygen
atoms the dinosaurs breathed???
Two Laws of Energy
 1st Law of Thermodynamics – Energy is neither
created or destroyed but can be transformed from
one form to another.
 2nd Law of Thermodynamics – Whenever energy
is converted from one form to another, some
usable energy (energy available to do work) is
degraded into heat (a less usable form that
disperses into the environment.)
*** Because of this, the amount of usable energy
available to do work decreases over time.
Example…
 When a car is driven, only about 20% of the
high-quality energy available in its gasoline
fuel is converted into mechanical energy (to
propel the vehicle) and electrical energy (to
run its electrical systems). The remaining
80% is degraded to low-quality heat that is
released into the environment and
eventually lost into space.
Example…
 When electrical energy flows through
filament wires in an incandescent light
bulb, it is changed into about 5% useful
light and 95% low-quality heat that flows
into the environment. In other words, this
so called light bulb is really a heat bulb.
Energy Efficiency
 A measure of how much useful work is
accomplished by a particular input of
energy into a system.
 ENERGY CAN NEVER BE RECYCLED OR
REUSED. IT IS ALWAYS TRANSFORMED
FROM HIGH QUALITY TO LOW
QUALITY ENERGY
What Does This Have to Do With
Food Chains and Food Webs?
 Food Chain
One way flow of energy
 Food Web
Energy flows between
many food chains
Vocabulary to know..
 Photosynthesis -
 Cellular respiration
 Chemosynthesis - Hydrothermal vents
What Does This Have to Do With
Food Chains and Food Webs?
A large percentage of the energy is lost between trophic levels.
This is as a result of the following:
 Some of the organism cannot
be eaten, e.g. bones, fur, etc.

Once eaten, some of the
organism cannot be digested.

Energy is lost in excretory
materials, such as urine.

Energy is lost in the form of heat
from respiration and body heat.
Let’s Practice…
 Give an example of entropy.
 Energy quality is a measure of an energy
sources’ ability to do useful work. What is
the difference in high quality energy and low
quality energy? Give an example.
 What are three interconnected factors that
life on Earth depends?
Let’s Practice
 State the 1st and 2nd Laws of Energy
(thermodynamics).
 Someone wants you to invest money in an
automobile engine that will produce more
energy than the energy in the fuel (such as
gasoline or electricity) you use to run the
motor. What is your response? Explain.
Let’s Practice…
 Use the 2nd energy law to explain why a
barrel of oil can be used as a fuel only
once?
 Why do you continuously need to eat
food?