Download The Living World - Mr D`Antoni`s Wonderful World of Science

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The biosphere is the layer around the Earth
containing all living organisms.
The other spheres are:
◦ Lithosphere
◦ Hydrosphere
◦ Atmosphere
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A biogeochemical cycle is a set of processes
by which an element passes from one
environment to the next and eventually
returns to its original environment, in an
infinite loop of recycling
There are two cycles we will be dealing with
◦ Carbon cycle
◦ Nitrogen cycle
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This biogeochemical cycle involves the
exchange of carbon on Earth
There are 9 parts to the carbon cycle
They are not steps which follow (1-9), but
rather a list of the different processes which
take place
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1- Photosynthesis : Plants using solar energy
to capture and convert atmospheric carbon
(CO2) into glucose (C6H12O6)
2- Ingestion : Animals eat plants or other
animals
3- Respiration : As living organisms breathe,
they exhale the carbon ingested back into the
atmosphere
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4- Decomposition of waste : Waste of animals
not released during respiration (urine, feces,
dead organisms, etc.) are decomposed by
organisms which emit CO2 and methane CH4
5- Forest fires – Combustion of tree trunks
and leaves are converted into CO2
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6- Shells and skeletons : Part of the carbon
dissolved in the water reacts with calcium to
form calcium carbonate (CaCO3) which is part
of shells and skeletons
7- Carbonate rock : The calcium carbonate
from the skeletons and shells accumulates at
the bottom of the ocean floor which forms
carbonate rock.
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8- Volcanic eruptions : When the carbonate
rock meets the magma, it melts and releases
some of the CO2 back into the atmosphere
9- Fossil fuels : When dead organisms fall to
the ocean floors, the carbon in them remains
buried in the sediment. This carbon can be
turned into fossil fuels (coal, oil and natural
gas)
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A biogeochemical cycle involving all the
exchanges of Nitrogen on Earth
There are 5 parts to the Nitrogen cycle
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1- Nitrogen Fixation : Certain bacteria take
atmospheric nitrogen and convert it to
ammonium (NH4+)
2- Nitrification : Bacteria oxidize ammonium
to form nitrites
3- Nitrogen absorption : Plants absorb the
ammonium and the nitrites. Herbivores only
source of nitrogen
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4- Decomposition of waste : Bacteria and
fungi break down nitrogen containing
substances. They produce ammonia which
then forms ammonium
5- Denitrification : Bacteria converts nitrates
into molecular nitrogen which returns to the
atmosphere.
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A biome is a large region of the world with
distinctive climates, wildlife and vegetation
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Flora = Plants
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Fauna = Animals
Terrestrial Biomes
Aquatic Biomes
Latitude
Salinity
Altitude
Turbidity (water clarity)
Temperature
Temperature
Precipitation
Direction and strength of the
current
Soil type
Presence of oxygen O2 and carbon
dioxide CO2 for respiration and
photosynthesis
Solar energy
Solar energy
Winds
Nutrients (type, amount, etc.)
Proximity to bodies of water
Water depth
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Terrestrial biomes are described mainly by
temperature and precipitation.
These factors determine the plant species
which can live there
The plants determine the animal species
which can live there.
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There are 7 terrestrial biomes on the Earth
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Tropical forests
Boreal forests
Temperate forests
Grasslands and shrublands
Arctic tundra
Deserts
Alpine
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The tropical forests are along either side of
the equator between the tropic of Cancer and
the tropic of Capricorn
The mean annual temperatures vary between
20°C and 34°C
The tropical forests have both seasonal
forests and evergreen forests
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Located in the Northern Hemisphere. Forms a
belt below the arctic.
Long cold winters. Long days in Summer.
Conifers, forest floor carpeted with moss and
lichen
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Located in southern Canada, the UnitedStates, Europe and part of Asia
Mean annual temperatures of 8°C to 10°C.
High precipitation throughout the year.
Northern regions of Quebec, mixture of
conifers and deciduous varieties. Farther
south, primarily deciduous trees.
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Many are located in central North America
In the temperate grasslands: Hot summers
and long cold winters. In the savannas: Hot
all year long
Grasses and shrubs. Three types: Temperate
grasslands, savannas, derived grasslands
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Located to the north of the boreal tundra.
Forms a ring around the North Pole
Long, cold winters. Very short summers.
Permanently frozen ground.
Grasses, stunted bushes, moss, lichen
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At all latitudes
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Low precipitations (less than 25cm per year)
Extreme temperatures
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Rare plant life
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Any high-altitude area in the world
Temperature varies according to altitude
(about 0.6˚C per 100m)
Vegetation zones: Submontane, montane,
subalpine, alpine and nival.
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Aquatic biomes cover a large area of the
surface of the Earth. (Approximately 75% of
the Earth)
Freshwater biomes cover about 2.5% of the
aquatic biomes and marine biomes cover the
remaining 97.5%
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Freshwater has a salinity of less than 0.05%
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Saltwater has a salinity greater than 3%
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There are 3 freshwater biomes and 3 marine
biomes
Lakes, Rivers and Wetlands for freshwater
Estuaries, Oceans and seas, and Coral reefs
for Marine
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Bodies of water surrounded by land and fed
by springs, rivers or precipitation
The organisms living there are
microorganisms, plants, plankton, fish,
amphibians, reptiles and birds.
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Streams and rivers that form permanently or
seasonal drainage channels for surface
drainage.
Moss, grass, fish, etc. live in rivers and
streams
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Includes marshes, swamps and peat bogs.
They are areas permanently or temporary
covered with water.
Life there includes plants which grow well in
water-saturated soil
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Broadening at the mouths of rivers acting as
a mixed zone between the maritime and river
environments.
Examples of organisms living there are
belugas, oysters and sponges
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Bodies of water that are subdivided according
to the depth of the water
Phytoplankton, crustaceans, fish, jellyfish,
mollusks, birds and mammals all live there.
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Environments characterized by the presence
of calcium carbonate produced by coral
Between 500,000 and two million plant and
animals species live there.
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What is a population?
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Density
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Distribution
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Biological Cycles
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A population is a group of individuals of the
same species, living in a shared space at a
specific point in time.
The population size refers to the number of
individuals in a population
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What can affect the size of a population?
Raise the population
Decrease the population
Birth
Death
Immigration
Emigration
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Counting individuals
◦ When possible, scientists will count every individual
of a population.
◦ This is not possible in a very large population, or in
a very large area.
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Counting by sample area
◦ By counting a small sample of a territory, scientists
can extrapolate from there to estimate the total
population
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Mark and Recapture
◦ Scientists capture a number of individuals and mark
them.
◦ Scientists return and recapture individuals again.
◦ By counting how many of the individuals were
recaptured, the total population can be estimated.
◦ Number of marked animals recaptured
=
◦ Total number of animals captured 2nd time
Number of marked animals
Population size
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The number of individuals in a given space
◦ Ex: 64927 people in 125 km2
 Ans: 519.416 people/km2
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How would you find the density of the
population of Canada?
◦ Population: 34,734,000 (2012 est.)
◦ Surface Area: 9,984,670 km2
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Density = 3.47/ km2
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1.Monaco
2.Singapore
3.Vatican City
4.Maldives
5.Malta
6.Bangladesh
7.Bahrain
8.Taiwan
9.Barbados
10.Mauritius
15,293/km2
6,843/km2
1,884/km2
1,328/km2
1,287/km2
1,199/km2
971/km2
714/km2
664/km2
637/km2
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Density
2
~3.5/km
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Size
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Size
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17,075,400 km2 (1st)
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9,984,670 km2 (2nd)
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Population
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Population
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143,030,106 (8th)
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34,754,000 (35th)
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Density
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Density
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8.3 (271st)
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3.5 (228th)
Russia
Canada
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Alternating rise and fall of population sizes
◦ They are of fixed duration and are repeated
continually
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Biotic factor (living)
◦ Related to the actions of living organisms
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Abiotic (non-living)
◦ Physical or chemical aspects of the environment.
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Birth rate
Disease
Amount of food
Predation
Competition
Human Activity
Biotic
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Amount of light
Soil or water pH
Terrain
Depth of snow
Temperature
Air Humidity
Abiotic
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Conditions can favour the predators or the
prey which will affect the other
◦ An increase in predators will cause a decrease in
the prey population
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If conditions go against the predators, they
wont be able to hunt and die off
◦ This will cause a massive increase in the prey
population
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A set of populations of
different species
sharing the same
habitat
Community
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Community of living
organisms interacting
with one another and
with nonliving
components of the
environment they
inhabit
Ecosystem
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What is Biodiversity?
◦ The relative abundance of the species in a
community
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What can affect the biodiversity of an
ecosystem?
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Competition
Predation
Mutualism
Commensalism
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Interaction between living organisms that
seek the same resource in their habitat.
Can be between individuals of the same
species (intraspecific) or between individuals
of different species (interspecific)
Both animals and plants can be competing for
a limit number of resources.
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If two predators are both competing for the
same prey, the more successful predator will
win out.
Two animals both trying to use the same site
for a habitat will also compete.
Plants will compete for light and water in a
forest or jungle. The plant that can get the
most light or water will be the winner.
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The interaction between two living organisms
where one feeds on the other.
The most obvious form of predation is one
animal eating another animal. Another form
is an animal eating a plant.
A specialised form of predator is a parasite
which lives directly on or inside it’s prey and
slowly feeds off of it.
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Interaction where both species benefit from
the relationship.
One example of this is the clown fish and the
sea anemone.
The anemone feeds by poisoning fish with it’s
tentacles and feeding off of them. The clown
fish has a mucus on it’s skin which blocks the
poison. The clown fish acts as bait for the
anemone’s prey and also uses the anemone
as a home.
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Another common example is a flowering
plant and a pollinator.
Without the flower, the pollinators would not
have food to eat
Without the pollinators, the plants would have
a much harder time to reproduce.
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Interaction where one organism benefits and
the second one is not affected
Seagulls and humans. They eat our garbage.
They benefit and it doesn’t affect us at all.
Also, birds who build their nests in trees. The
birds get shelter and safety, the tress are
unaffected.
Type of interaction
Competition
Predation
Mutualism
Commensalism
Effect on population A
Effect on population B
Type of interaction
Competition
Predation
Mutualism
Commensalism
Effect on population A
Effect on population B
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What is an ecosystem?
◦ A community of living organisms interacting with
one another with the nonliving components of the
environment they inhabit
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An ecosystem can be anything from an
aquarium to a lake or a forest
In an ecosystem there are 3 trophic levels.
◦ Producer, consumer and decomposer
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These are organisms which can transform
inorganic matter into organic matter.
Inorganic matter is something not produced
by a living organism
◦ Ex. Water, mineral salts
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Organic matter is used in the composition of
living organisms and is usually created by
them.
◦ Ex. Protein, lipids, carbohydrates
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These are typically organisms such as plants,
algae and certain bacteria
They are said to be autotrophs
◦ Means they can feed themselves.
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They can feed themselves by photosynthesis
and by absorbing nutrients from the soil.
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Heterotrophic organisms that feed on other
living organisms.
◦ Heterotrophic means they need others to feed.
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Primary consumers feed directly on producers
Second, third or fourth consumers eat
consumers which are below them.
This is all part of the food chain.
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What type of consumer would a herbivore be?
◦ First
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What type of consumer would a carnivore be?
◦ Second or higher
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What type of consumer would an omnivore
be?
◦ Any level
◦ An omnivore is an organism which eats plants and
animals.
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Organisms that feed on the waste and
remains of other living organisms.
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This trophic class consists of certain worms,
some bacteria, all fungi and certain insects.
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They can also be prey to consumers.
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They break down the organic matter into
inorganic matter so that it can be used all
over again.
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Law of Conservation of Mass
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Nothing is created, only transformed
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Inorganic material becomes organic then
becomes inorganic again
Nature is one big recycler...
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Energy is produced from inorganic sources by
producers
Energy is then transferred to consumers by
eating the producers
The waste and decaying bodies of the living
are decomposed by the decomposers and
converted back to inorganic matter
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Biomass is all of the living matter in a given
Ecosystem
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This will be different for each ecosystem
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Primary Productivity is the amount of new
Biomass being produced by the producers of
a given ecosystem
The Primary Productivity can be influenced by
four abiotic factors
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1- Light
◦ Necessary for photosynthesis
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2- Water
◦ Also necessary for photosynthesis
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3- Essential Nutrients
◦ These include Nitrogen, Carbon, Phosphorous and
Potassium
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4- Temperature
◦ Temperature can have an influence on production
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A Disturbance is an event that damages an
ecosystem. It can lead to the elimination of
organisms and alter the availability of
resources
Disturbances can be of different types. They
can be something like snowstorms,
sandstorms, hurricanes or volcanic eruptions
Some are more frequent, like seasonal
flooding, and some are less frequent, like a
flood caused by torrential rains.
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Disturbances can also be more or less serious
in nature. A small ice storm which lasts only a
few hours will cause much less damage than
one that lasts a few days. That was the case
in the ice storm of 1998 in Quebec
Disturbances can either be natural or human
in origin.
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They are events triggered by environmental
phenomena rather than humans, but damage
ecosystems nonetheless.
Every single ecosystem can be effected by a
natural disturbance no matter how remote
they may be.
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Volcanic eruptions
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Forest fires
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Drought
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Floods
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Periods of frost
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Heat waves
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They are events that are triggered due to
human activity.
Many human activities damage ecosystems
They can be small scale, such as littering, or
large scale like oil spills or deforestation
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After an ecological disturbance, an ecosystem
will undergo a series of gradual changes,
sometimes spread over hundreds of years
The ecosystem will try to obtain a state of
balance
Ecological succession is the series of changes
that occur in an ecosystem after a
disturbance and that continue until the
balance of the ecosystem is restored