Transcript Document

Science Knowledge: Science 2: Life
Processes and living things
K2.5 Living things in their environment
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Download K2.5_2.0a Authored by Liz Lakin SMC and Keith Ross,
University of Gloucestershire. accessed from
http://www.ase.org.uk/sci-tutors/
date created September 2006
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Stardust,
Take-over bids
and Biodiversity
17/07/2015
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Learning Outcomes
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To explore the science behind the
headlines
To establish a timeline of events leading
to our current scientific understanding
To identify the ‘big ideas’ in this field of
biology and recognise how they are
interlinked
To explore human Impact on biodiversity
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Introduction
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What do you understand
by the term ‘Biodiversity’?
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Biodiversity
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Genetic diversity
Species diversity
Habitat diversity
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Topics for Discussion
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Where do you think we come from
and where are we heading?
Are we made of ‘stardust’?
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History of the Universe
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What are your own beliefs?
What do scientists believe?
What evidence do we have
that the Big Bang occurred?
A universe thought to be 13
thousand million years old, with the
solar system evolving 4.5 thousand
million years ago
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If this was a 24hr clock:
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Solar system at 4pm
Multicellular life at 11pm
Dinosaurs extinct at 6 mins to midnight
Earliest hominids in last 30 seconds
Modern man in last second of the day
Agriculture and civilisations within the
last 1/10th of a second
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The big ideas …
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Emergence
and evolution
of life
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Feedback
 Stability
 Change
 Unpredictability
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Origins of Life on Earth
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Stanley Millar
Other theories
From RNA to DNA
Last Universal
Common Ancestor
(LUCA) – New Scientist 3 Sept 05
pp.26-29
http://www.globalchange.umich.edu/globalchange1/current/lectures/complex_life/complex_life.html
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Take-over bids
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DNA to life on Earth
Bacteria to complex cells
Prokaryotes – bacteria
Eukaryotes – plants and
animals
Cambrian explosion and
specialisation
Mass extinctions
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Burgess Shale fauna
www.karencarr.com/ gallery_hallucigenia.html
trilobites (1) Hallucigenia (20) Wiwaxia (26),
©2002 by S.M. Gon III (composition & linework) & John Whorrall (color rendering)
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The Emergence of Complex Life
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http://www.globalchange.umich.edu/globalchange1/current/lectures/complex_life/complex_life.html
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Classification of life
Five Major Kingdoms:
 Monera Bacteria and Archaea
 Protista simplest eukaryotes
 Fungi eukaryote
 Plants
 Animals
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Darwinian Evolution
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Adults give birth to large numbers of young.
Population sizes remain the same.
Competition exists.
All organisms vary.
Some variations are more advantageous than
others.
Advantageous variations will be passed on.
Under the correct conditions, this could lead
to EVOLUTION.
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Feedback
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Positive – change (runt?)
Negative – stability (thermostat?)
How does this relate to life on
Earth?
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Positive feedback
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Which one of the following statements
describes the science of chaos or complexity
(illustrated by the 'butterfly effect')?
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It explains why it is impossible to predict the
effect of human-induced changes on ecosystems
and climate.
It applies only to complex systems which are at
equilibrium.
It explains why there is stability and
predictability in a very complex world.
It relies on negative feedback.
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Environmental Influence
ATMOSPHERE
HYDROSPHERE
BIOSPHERE
GEOSPHERE
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Human impact …
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The nitrogen taken in by plants is used
directly in which one of the following?
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Supplying energy
Carbohydrate formation
Photosynthesis
Making protein
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Fertiliser run-off into a lake can cause what is
known as eutrophication, killing living organisms
in the lake.
One of these statements is not part of this process
1.
2.
3.
4.
The extra nutrients in water cause algae to
grow very quickly.
Algae growth blocks out the sun causing
the lake vegetation to die.
The growth of algae removes oxygen from
the water, causing water animals to die.
Bacteria decompose the dead plants and
animals, causing the decaying appearance
of the lake.
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Global Climate Change
Indicators
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Conservation & Good
Practice
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So, what is being done?
Is it really enough?
More research,
 More education,
 Greater understanding leads to
greater doing …
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Summary
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Origin of life (evolution)
Feedback and adaptation
Chaos & unpredictability
natural changes (ecology)
 Human induced changes (sustainability)
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