Dendrochronology is the science of studying tree growth rings to determine past environmental conditions. Trees record information about forest fires, floods, droughts, meteorite strikes, volcanic eruptions, and ice ages in their growth rings. By examining a tree's core sample or cut-down tree, scientists can see the tree's life and evidence of climate changes, fires, and variations in sunlight intensity over time. Trees need sunlight, water, minerals, and the right temperature conditions to grow and produce growth rings through photosynthesis, cell meiosis, cell mitosis, and water-based cell division and multiplication processes.

1. Dendrochronology
by Annie Cloutier 2012 copyright
the science of studying growth rings of a tree to
determine past conditions
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2. Trees quietly hold Earth’s secrets...
forest fires forestfire-hutto.jpg 382×287 pixels
floods
droughts 701.jpg 480×516 pixels
meteorites meteor-strike.jpg 1,024×768 pixels
volcanic explosions
Ice Ages
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3. The last Ice Age
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4. When a core is drilled from a living tree, or, the tree is cut down, the inside
of the tree is visible. We can read the life of the tree and the events of climate
change, fires and even how brightly the sun shone.
http://www.youtube.com/watch?
v=TfZnp09lkHk&feature=related
New Zealand University of Aukland Dr. Gretel Boswjik
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5. Measuring the growth of early wood
to late wood rings equals an annual
tree year
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6. What does a tree need to live ?
sunlight -> photons of solar energy for
photosynthesis
water
water soluble minerals and elements
temperatures for the tree’s zone
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7. Processes necessary for a tree to grow
photosynthesis
cell meiosis
cell mitosis
WATER is a key component in cells
being able to divide and multiply
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8. Meiosis in trees
`http://www.youtube.com/watch?v=D9byVQxvMXs
the process of two sequential nuclear
and cellular divisions resulting in four
haploid cells from a single diploid
cell:this occurs in reproductive organs
such as pollen and ovules in coniferous
trees
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9. Mitosis
http://www.youtube.com/watch?
the nuclear division of somatic cells
resulting in two genetically identical
daughter nuclei
nuclear is having a nucleus in center
somatic cells are a body cell other than sex cells containing at least
two sets of chromosomes inherited by both parents
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10. Clones are genetically identical organisms
Spider plant plantlet was a clone of
parent Spider plant
Coleus cutting will make a clone of
parent plant
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11. http://www.youtube.com/watch?v=Q6ucKWIIFmg
the end is just another beginning some
where in nature
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