Springfield Central High School
What is a population in biology?
What is population dynamics?
What are the three phases that we can find a population in?
What is exponential growth?
What is logistic growth?
What restriction can there be on population growth?
What are immigration and emigration?
What does an age structure diagram show??
What is carrying capacity (K)?
What is extinction?
How do humans impact other populations?
Answer two of these questions.
Food Chains Vs Food Webs
This lesson is about how energy and matter move through an ecosystem.
How are food chains and food
webs different?
Available energy in the ecosystems is captured by autotrophs and turned
into organic molecules that store energy. That energy can be passed from
organism to organism and eventually back to the ecosystem.
Scientists make models to show this movement of energy in an ecosystem.
Life is Powered by the Sun. Essentially all life on earth is powered by the
energy released from the sun.
There are exceptions to
the sun being the
energy source for life
on earth.
There are ecosystems at
the ocean floor that rely
on the energy in certain
molecules for energy
How does the sun’s
energy animate life
on earth?
What are
exceptions to life
requiring the sun’s
energy?
Autotrophs are often called the producers. The autotrophs produce the
organic molecules, (sugars) that living organisms rely on for energy.
There are two types of autotrophs:
Phototroph (photosynthetic autotroph)
What are
Chemotroph (chemosyntheric autotroph)
autotrophs?
Why are
autotrophs
called the
producers?
Here we have
examples of
two
hypothetical
food chains.
One powered
by the sun
the other by
molecules
that store
energy.
Organisms that use energy from the sun to manufacture their own
nutrients, (which can then be passed on to other organisms) are called
photosynthetic autotrophs (aka. phototroph or Photoautotroph)
Examples of phototrophs:
Cyanobacteria: A member of the
eubacteria domain and kingdom that
uses photosynthesis to produce
chemical energy from the sun’s light.
Green algae: A Green algae is a
protist that uses photosynthesis to
produce sugar.
Plants: Most plants use photosynthesis
to transform light energy to
carbohydrates, (chemical energy).
Photosynthetic autotrophs capture
sunlight and transform it into chemical
energy.
What is photosynthesis? What are
the three types of photosynthetic
organisms?
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Found in plant cells, animal cells do not contain
chloroplasts.
Contains chlorophyll pigments which gives plants their
green color.
Thylakoids and stroma are found in the chloroplasts.
Thylakoids are the site of light reaction. Stroma is where
the light independent reaction occurs.
Site of photosynthesis.
Function:
◦ To produce glucose from carbon dioxide, water, and light.
Explain what a
chloroplast is and what
its function is.
Plants evolved from green algae which evolved from cyanobacteria.
Cyanobacteria:
Cyanobacteria uses photosynthesis to produce
chemical energy from the sun’s light.
Cyanobacteria is a member of the kingdom
eubacteria, and is found living as individual
cells or in colonies.
Cyanobacteria-like organisms' fossils have been
discovered aging back 3.5 billion years ago.
Cyanobacteria are like
free living
chloroplasts.
What are
cyanobacteria, and
why are they
important to
biology?
Cyanobacteria and Endosymbiosis
Cyanobacteria are known to live together with, and in close association
with, other organisms in a mutualistic relationship.
Example: Lichens are organisms made
from a mutualistic/symbiotic relationship
between fungus and photosynthetic
autotrophs like cyanobacteria.
Learn why cyanobacteria’s
ability to form mutualistic
relationships has led
scientists to recognize the
origin of chloroplasts
Endosymbiotic Evolution
Many scientists have concluded that some of the specialized cell
structures, (organelles) found in eukaryote cells are ancestrally related to
free living bacteria that formed mutualistic relationships with ancient
eukaryote cells.
Two examples are: mitochondria and Chloroplasts.
Chloroplasts turn light energy into chemical energy, (sugars)
Mitochondria turn sugars into another form of chemical energy
that cells actually use (ATP).
Chloroplasts are believed to have evolved from cyanobacteria.
Evidence: Chloroplasts have their own cell membranes,
their own DNA, which is bacterial DNA, one of cyanobateria
strategies for survival is forming endosymbiotic
relationships
Once cyanobacteria had been established in eukaryotic cells we have the
evolution of photosynthetic protists such as phytoplankton and green algae.
Explain endosymbiotic evolution.
Green Algae and
plants are both
eukaryotic
organisms which,
(usually) contain
chloroplasts in
their cells
Plants have a more
complex
reproductive
system than do
algae.
The photosynthetic
capability of algae
and plants is due to
the chloroplasts.
Discuss the
evolution of
plants.
Organisms that cannot produce their own nutrients and must feed on
other organisms are called heterotrophs.
Herbivores are heterotrophs that feed on autotrophs:
Plant eaters.
Carnivores are heterotrophs that feed on other heterotrophs:
Meat eaters
Omnivores are heterotrophs that eat both autotrophs and heterotrophs:
Meat and Plant eaters
Detritivores (decomposers) are heterotrophic organisms that break down
and absorb nutrients from dead organisms.
Many fungi and bacteria as well as some protozoans fill this niche
Heterotrophs are called the
consumers.
Heterotrophs consume the organic
molecules that autotrophs make.
Heterotrophs consume the organic
molecules that are in other
heterotrophs.
Heterotrophs consume the organic
molecules that store energy for food.
The chemical energy consumed by heterotrophs was energy transferred
from light energy into chemical energy by autotrophs.
We now know that photosynthesis is the process of turning light energy
into carbohydrates, (sugars)
Respiration
Respiration is how organisms
turn carbohydrates into ATP, the
chemical energy that is used in
the cells of organisms.
Respiration happens in, (the
other endosymbiont organelle)
the mitochondria
Let’s look at the interaction
Between Chloroplasts and
Mitochondria.
This is One of the key things to
know in high school biology.
Discuss the interaction and
interdependence of chloroplasts and
mitochondria. Watch the O2
Note that the products of photosynthesis are used in respiration,
and that the products of respiration are used in photosynthesis.
•Chloroplasts
are the site of
photosynthesis.
•Photosynthesis is the
production of sugar
•Chloroplasts evolved from
cyanobacteria
•Mitochondria
are the site of
cellular respiration.
•Respiration is the release of
energy stored in sugar
•Mitochondria evolved via
endosymbiosis
Based on the symbiotic relationships and feeding relationships, biologists have
made models to explain the flow of energy and matter through ecosystems.
Food Chains
Food chains are the simplest model for energy and matter flow through
an ecosystem.
Nutrients and energy
proceed from autotrophs
to heterotrophs and
eventually decomposers.
Food chains are limited
to only 3 to 5 links. At
each link, energy is lost
as heat.
Each arrow represents
the transfer and loss of
energy .
Explain the
significance of
food chains.
Examples of food chains.
Each organism in a food chain
represents a feeding level known
as a trophic level.
A Food Chain can also be represented
as an ecological pyramid.
The ecological pyramid model give
more information than the classic
food chain model.
The energy available at each
trophic level can be represented in
a pyramid shape as can
the number of organisms at each
trophic level.
Explain how each trophic
level on a food chain or
food pyramid indicates
available energy.
Trophic Dynamics
Scientists will often
represent changes
happening at each trophic
level.
Compare
the
available
energy at
each trophic
level to the
number of
organisms
at each
level.
Food Webs
A food web is a more complex model showing the multiple food chains
that exist in ecosystems.
A food web is a model to express the multiple relationships at each trophic
level in a community.
We have seen energy and matter travel through the ecosystems using
the food chain, ecological pyramid and food web models.
Elements and molecules also move through ecosystems and the
biosphere and can be traced using another type of model, the
biogeochemical cycles model.
"Bio", of course, refers to the living part of these cycles, while "geo"
refers to the earth. In the word, biogeochemical, "chemical" refers to
what is cycling between the biotic and abiotic. A chemical is anything
with a chemical symbol or chemical formula.
This part of the lesson is about
how elements cycle through the
earth’s environment.
•Why do elements need to cycle
through the biosphere; as
opposed to energy that can
flow through the ecosystems?
•Does energy arrive on earth
every day?
•Does matter arrive on earth
everyday?
Element
Nutrient
Biological
Form
Primary Abiotic
Reservoir
Primary Abiotic
Reservoirvoirs
What elements
are CHONPS? Atmospheric
Carboydrates
Hydrologic
=
(CH2O)n Oxygen, Nitrogen,
CO2
COSulfur
Carbon, Hydrogen,
Phosphorous,
3 and HCO3
proteins,
Geologic
Carbon is the key element
for lipids,
life.
amino
acids.things come from? Carbon dioxide
CaCO3,or
Coal,
Where does the carbon
in living
Petroleum
other living things
We all know that hydrogen and oxygen are found in water; these elements
Nitrogen
Proteins and
other (carbohydrates)
Atmospheric
Hydrologic
are also N
the key components
of sugars,
and fats,
(lipids).
Nitrogen
nitrogen gas N2
ammonium NH4+
Where in living organisms do we find these other elements, and where? containing organic
nitrate NO3
Where in the lithosphere
do we find these elements?
molecules
nitrite NO2Carbon C
Phosphorus P
DNA, ATP,
Phospholipids
Sulfur S
Certain Amino
Acids
and Vitamins
Hydrologic
Where
do living
dissolved
things
getphospate
the
3PO4
nutrients
that
they need? Where
are these
Geologic
Atmospheric
sulfate rocks SO42-nutrients
H2S, SO2,stored
SO3,
in H
the
biosphere?
2SO
4
Geologic
phospate rocks
PO43-
Hydrologic
SO42- and H2SO4
There are many cycles in nature that model the movement of elements
or chemicals.
Examples of non-biogeochemical cycles that effect the
biogeochemical cycles:
Rock cycle: Silicone (Si)
Essentially the entire periodic table of elements cycle in the rock cycle.
Explain how the rock
cycle effects the
biogeochemical cycles.
Describe the water
cycle and this
cycle’s impact on
life.
Life depends on H2O
H2O cycles through the environment:
Water is pulled from the
ground by plants’ roots. Water
is lost from plant leaves by
transpiration, which causes
negative pressure in the
roots. Water evaporates from
bodies of water. Water as a
gas, collects as clouds. Water
condenses in clouds as
precipitation and falls to the
ground.
Tell the story of the
carbon cycle.
The carbon cycle is a true biogeochemical cycle.
All living things are made with the element carbon.
More than any other element, carbon is the element of life.
Atoms of carbon form the framework for proteins, carbohydrates, lipids, and
nucleic acids. (The 4 key molecules of living things).
The carbon cycle starts with photosynthetic autotrophs. Photosynthesis
converts water and carbon dioxide into energy rich carbon molecules:
glucose. Autotrophs use the energy stored in this molecule for energy.
Notice the roles of O2 and CO2 in this cycle.
Heterotrophs directly or indirectly feed on
autotrophs and also use there carbon molecules
for growth and energy. Carbon dioxide is
released as organisms use the energy in carbon
molecules.
Carbon is stored in the organic matter found in
soil. This organic matter is called detritus.
Carbon is also stored out of the cycle in coal
and petroleum reserves. Fossil fuel burning
frees this carbon as carbon dioxide.
Tutorial
Animation
Animation
The O cycle follows the movement of oxygen from the atmosphere to the
biosphere and into the lithosphere.
Oxygen is taken out of the atmosphere by photosynthesis.
Photosynthesis produces the organic molecules that contain oxygen and
support the living things in the biosphere.
Through respiration and from the decay of living organisms oxygen enters the
rock cycle (ie the lithosphere).
Compare
the
oxygen
cycle and
the carbon
cycle.
Why are
they so
similar?
Tell the story of the
nitrogen cycle.
78% of the atmosphere is nitrogen in the form N2.
Photosynthetic autotrophs, (like plants) can not use the N2 form of nitrogen
Nitrogen is a key component of proteins.
Proteins are one of the key molecules that make living things.
Nitrogen Cycle
Atmospheric nitrogen (N2) is transformed into a form of nitrogen that can
be used by photosynthetic autotrophs in 3 ways:
Lightning,
certain bacteria that live in a mutualistic relationship with legume
plants,
human nitrogen fertilizer factories.
Plants need nitrogen as nitrates (NO3) or ammonium (NH4). Plants and
other autotrophs use nitrogen to produce proteins. df
Plant protein is broken down for its nitrogen by animal heterotrophs to
build animal proteins.
Urine; animal waster, contains excess nitrogen.
Other forms of bacteria break down organ matter and nitrates back into
atmospheric nitrogen.
Volatilization which is substances turning into gas, returns nitrogen
to the atmosphere. This is the bad smell near farms and open toilets.
Animation
ANIMATION
Animation
All organisms require phosphorus for growth and development.
Phosphorus is an essential element in all cell membranes.
Tell the story of the
two phosphorus cycles.
The phosphorus cycle is actually two cycles, a
short term cycle and a long term cycle.
The short term cycle phosphorus cycle begins
when plants obtain phosphorus from the soil.
Animals obtain phosphorus by eating plants.
Animals and plants die and the phosphors in
their bodies is returned to the soil.
The long term phosphorus cycle begins when
phosphorus is leached out of soil and into
streams. Phosphorus washes into the oceans.
Phosphorus in the oceans is incorporated into
rocks and insoluble compounds.
Millions of years later as the environment
changes, the rocks containing phosphorus is
exposed and begins to erode into sediments. the
phosphorus again becomes part of the soil and
can enter the short term or long term P cycle.
Animation
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Central Concept: Ecology is the interaction among organisms and
between organisms and their environment.
6.1 Explain how birth, death, immigration, and emigration
influence population size.
6.2 Analyze changes in population size and biodiversity
(speciation and extinction) that result from the following: natural
causes, changes in climate, human activity, and the introduction of
invasive, non-native species.
6.3 Use a food web to identify and distinguish producers,
consumers, and decomposers, and explain the transfer of energy
through trophic levels. Describe how relationships among
organisms (predation, parasitism, competition, commensalism,
mutualism) add to the complexity of biological communities.
6.4 Explain how water, carbon, and nitrogen cycle between abiotic
resources and organic matter in an ecosystem, and how oxygen
cycles through photosynthesis and respiration.
What are biotic and
abiotic factors in an
ecosystem?
Give examples of
abiotic factors that
effect living things.
What is the source of energy that animates life on earth?
What are autotrophs?
What are the two types of autotrophs, and how are they different?
What is photosynthesis?
What is cyanobacteria?
What is endosymbiotic evolution?
What is a chloroplast?
What herbivores, carnivores, omnivores and detritivores?
What is repriration?
What is ATP?
What
What
What
What
is
is
is
is
the relationship between chloroplasts and mitochondria?
a food chain?
a trophic level?
a food web?
What are biogeochemical cycles??
Where are carbon, nitrogen, phosphorus, oxygen and hydrogen found in
living organisms?
Where are carbon, nitrogen, phosphorus, oxygen and hydrogen found in
abiotic sinks in the earth or atmosphere?
What is the rock cycle?
What is the water cycle?
What is the carbon cycle?
What is the nitrogen cycle?
What is the oxygen cycle?
What is the phosphorus cycle?