Transcript Food Chains and Food Webs

Introduction to Biology-1
• Remember:
– An independent variable is the
variable that YOU have control
over
– A dependent variable is the
variable that RESPONDS to what
you do.
– A control group is the group that
does not receive the treatment.
• Read the scenario.
– What is the independent variable?
– What is the dependent variable?
– What would be a good control
group?
– What conclusion could the
students make based on the
results?
• A group of students hypothesize
that the amount of alcohol
produced in fermentation
depends on the amount of
glucose supplied to the yeast.
They want to use 5%, 10%, 15%,
20%, 25%, and 30% glucose
solutions. These are the data:
% Glucose
Amt of alcohol (μl)
5
1
10
13
15
24
20
30
25
39
30
44
Introduction to Biology
• Remember:
– An independent variable is the
variable that YOU have control
over
– A dependent variable is the
variable that RESPONDS to what
you do.
– A control group is the group that
does not receive the treatment.
• Read the scenario.
– What is the independent variable?
– What is the dependent variable?
– What would be a good control
group? 0% glucose
– What conclusion could the
students make based on the
results? more alcohol is produced
at higher glucose concentrations
• A group of students hypothesize
that the amount of alcohol
produced in fermentation
depends on the amount of
glucose supplied to the yeast.
They want to use 5%, 10%, 15%,
20%, 25%, and 30% glucose
solutions. These are the data:
% Glucose
Amt of alcohol (μl)
5
1
10
13
15
24
20
30
25
39
30
44
Characteristics of Life-2
• Read the scenario and, on
your answer sheet, underline
all of the characteristics of life
that the organism shows.
• Sharks have many sub-species.
This is a result of them
evolving over time to fill an
available niche. Although
sharks do not have bones,
they are made of cartilage.
They are a multi-celled
organism. They reproduce and
give birth to live young. They
are carnivorous, feeding only
on meat. Most sharks are
cold-blooded, although a few
species are warm-blooded.
For both, it is vital that they
maintain homeostasis.
Characteristics of Life
• Read the scenario and, on
your answer sheet, underline
all of the characteristics of life
that the organism shows.
• Sharks have many sub-species.
This is a result of them
evolving over time to fill an
available niche. Although
sharks do not have bones,
they are made of cartilage.
They are a multi-celled
organism. They reproduce
and give birth to live young.
They are carnivorous, feeding
only on meat. Most sharks are
cold-blooded, although a few
species are warm-blooded.
For both, it is vital that they
maintain homeostasis.
Food Chains and Food Webs-3
• Identify a food chain in the
food web with four
organisms. Write it down.
• Label the producer, primary
consumer, secondary
consumer, and tertiary
consumer.
• How much energy is
transferred between each
trophic level?
• What is the difference
between a food web and a
food chain?
Food Chains and Food Webs
• Identify a food chain in the
food web with four
organisms. Write it down.
• Plant (P) Grasshopper (1st
C)frog (2nd C) owl (3rd C)
• Label the producer, primary
consumer, secondary
consumer, and tertiary
consumer.
• How much energy is
transferred between each
trophic level? 10% moves up
• What is the difference
between a food web and a
food chain? More complex
and realistic
Carbon Cycle-4
• Examine the picture
below. Answer the
questions that follow.
• How does carbon enter
the food chain?
• What two ways are
humans negatively
impacting the carbon
cycle?
–
–
• How are nutrient cycles
different from energy?
Carbon Cycle
• Examine the picture
below. Answer the
questions that follow.
• How does carbon enter
the food chain?
• CO2 picked up by plants
• What two ways are
humans negatively
impacting the carbon
cycle?
– burning FF
– deforestation
• How are nutrient cycles
different from energy?
• Matter cycles energy
travels in one direction
Water Cycle-5
• Examine the picture
below. Answer the
questions that follow
• Record the five steps of
the water cycle.
• What is it called when
water evaporates from
living tissue?
Water Cycle-5
• Examine the picture
below. Answer the
questions that follow
• Record the five steps of
the water cycle.
–
–
–
–
–
Evaporation
Condensation
Precipitation
Runoff
infiltration
• What is it called when
water evaporates from
living plants?
– transpiration
Nitrogen Cycle-6
• Examine the picture.
Answer the questions
that follow.
• What organism is
responsible for fixing
nitrogen so that it is
usable by plants?
• How do consumers get
their nitrogen?
• How is nitrogen
returned to the soil?
Nitrogen Cycle
• Examine the picture.
Answer the questions
that follow.
• What organism is
responsible for fixing
nitrogen so that it is
usable by plants?
• bacteria
• How do consumers get
their nitrogen?
• Eat someone
• How is nitrogen
returned to the soil?
• Decomposition or N
fixation
Levels of Organization-7
• Examine the picture
below. Answer the
questions that follow.
• Identify and DEFINE the
levels of organization.
• What is a biotic factor?
– List four biotic factors
from the picture.
• What is an abiotic
factor?
– List four abiotic factors
from the picture (may
be inferences).
Levels of Organization
• Species-able to reproduce
& produce fertile offspring
• Population- same species
same area
• Community- many
populations in same area
• Ecosystem- area including
both the biotic and abiotic
factors (biome= specific
ecosystem)
• Biosphere-all of planet tha
supports life
• biotic factor?
• Living or formerly living
–
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–
Populations
Food
Waste
mates
• abiotic factor?
• Nonliving but needed
for living things
–
–
–
–
Air
Water
Space
temperature
Population Growth-8
• What kind of growth is
in the graph below?
• What must be true for
this type of growth to
occur?
• What kind of growth is in the
graph below?
• What does the line “K”
represent?
• What causes “K” to occur?
– What are some examples?
Population Growth
• Exponential or J curve
• NO limiting factors
• Logistic or S curve
• K= carrying capacity
• Environmental pressures
limiting factors
– Food
– Water
– space
Density Dependent versus
Independent-9
TORNADO
• Examine the pictures and
place them under the
appropriate categories.
FOOD
SPACE
DISEASE
FIRE
COMPETITION
PREDATION
Density Dependent versus Independent
Density dependent
• Food competition
• Predation
• Disease
• space
FOOD
Density independent
• Storms
• fire
TORNADO
SPACE
DISEASE
FIRE
COMPETITION
PREDATION
Types of Competition-10
• What is the difference
between interspecific
competition and
intraspecific
competition?
• Which picture shows
which type of
competition?
Types of Competition
• interspecific
competition 
between different
species
• intraspecific
competition 
between same species
• Which picture shows
which type of
competition?
intraspecific competition
interspecific competition
Symbiosis-11
• What is symbiosis?
• The picture below shows
mutualism. WHY?
• The picture below is an
example of commensalism.
What does this mean?
• This tick is feeding off of a
dog. What is this an
example of?
Symbiosis
• Symbiosis is when two
different species live closely
together
• in mutualism both benefit
• In commensalism one
benefits and the other is
not harmed or helped
• This tick is feeding off of a
dog.
• Parasitism
Succession -12
• Primary Succession
– Write down the steps of primary succession.
– What is the purpose of lichen in primary succession?
• Primary Succession
Succession
– Bare rock is exposed
– Pioneer species like moss or lichen grow on rock making
soil
– Grasses come in
– Shrubs come in and are slowly replaced by trees and a
then a mature climax community
– Lichen is a fungi algae & mutualist that can grow on rock
and help form soil
Succession-13
• Secondary Succession
– Write down the steps of secondary succession.
– How is secondary succession different from primary
succession?
• Secondary Succession
Succession
– Something happens to an area disrupting and destroying the
living things but leaving soil
– Grasses and small plants come in
– Larger plants shrubs and fast growing trees come in as do
more animals
– A mature, climax community develops
– Secondary succession starts with soil while primary
succession starts with bare rock
Succession-14
• Which type of succession will happen faster?
– Why?
• Using the pictures below, which natural disaster
would cause primary succession to occur?
• Using the pictures below, which disasters would
cause secondary succession to occur?
Clear Cutting
(deforestation)
Forest Fire
Volcanic Eruption
Succession
• Secondary succession occurs faster because soil is
already present (soil takes a looooong time to form)
• Primary succession would occur after a volcanic
eruption
• Secondary succession would occur after a fire or
clear cutting
Clear Cutting
(deforestation)
Forest Fire
Volcanic Eruption
Threats to Biodiversity-15
• Biomagnification
– Biomagnification is the
build up of a persistent
toxin within a food
chain.
– Summarize the picture
– Who is most affected?
Threats to Biodiversity
• Biomagnification
– Biomagnification is the
build up of a persistent
toxin within a food
chain.
– As the toxin moves up
the food chain it
becomes more and
more concentrated
– So, the top predator
received the most
poison
Threats to Biodiversity-16
• Is the greenhouse
effect a good
thing or a bad
thing? Why?
• Is global warming
a good thing or a
bad thing? Why?
• Why is global
warming a
concern? What
are humans doing
that may cause
this to occur?
Threats to Biodiversity
• The greenhouse effect a
good thing because it
keeps our planet warm
• Global warming may be
bad thing and it may be
happening faster than
normal
• Rising sea levels,
changing habitats
• Burning of fossil fuels,
coal, oil and natural gas
Desert-17
• Very hot
• Dry
• Vegetation includes
cacti
• Record the desert
characteristics on your
paper.
• Think of two ways an
animal might adapt to
the desert biome?
• Think of two ways a
plant (such as a cactus)
might adapt to the
desert biome?
Desert
• Very hot
• Dry
• Vegetation includes
cacti
• animals
• Conserve water by little
waste
• Being nocturnal
• plants
• Waxy coating to
decrease water loss
• Spongy inner tissue to
store water
Temperate Deciduous Forest-18
• Our biome!
• Four seasons
• Deciduous and
coniferous trees
• animal
• Hibernate when it is
cold
• Shed in summer, grow a
thick coat in winter
• Plant
• Lose leaves to save
energy in winter with
less sunlight
• Broad leaves to catch
lots of light during
summer
Temperate Deciduous Forest
• Our biome!
• Four seasons
• Deciduous and
coniferous trees
• Record the biome’s
characteristics on your
paper.
• Think of two ways an
animal may adapt to
this biome.
• Think of two ways a
plant may adapt to this
biome.
Tropical Rainforest-19
• Humid
• Wet
• Has the most
biodiversity!
• Being torn down all the
time!
• Record the biome’s
characteristics on your
paper.
• What does biodiversity
mean?
• Why is biodiversity so
important to humans?
Tropical Rainforest
• Humid
• Wet
• Has the most
biodiversity!
• Rapidly being
destroyed!
Biodiversity is a variety of
living organisms in an area
Biodiversity is important
because of the beauty,
and value of the living
organisms for food,
medicine and resources
Tundra-20
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Cold, harsh winters
Little precipitation
Layer of permafrost
Vegetation cannot grow
very tall.
• What kind of animal
(ex: reptile, mammal,
etc.) can live here?
– Why?
• Why do you think many
of these animals are
white?
• Why do you think
vegetation cannot get
very tall?
Tundra
• Cold, harsh winters
• Layer of permafrost
• Vegetation cannot grow
very tall.
• Animals that can live here
are tolerant of cold artic
fox or have short
lifecycles mosquitos
• They may migrate to
warmer areas, too elk
• White fur or feathers acts
as camouflage
• There is too little soil and
water for many plants to
grow tall so there are
only short plants