7.4 How did Life Develop?
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Lesson duration is: 45 minItems in this lesson
Slide 1 - Slide
A fossil is...
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0:20
A
A very old bone or other body part
B
A decayed old bone or other body part
C
A petrified (stone) shape of a bone or other body part
D
An imprint in rock of an ancient animal or plant
Slide 2 - Quiz
Which is not a fossil?
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0:20
A
Pollen grains inside an ancient clay pot
B
A pawprint of a dinosaur in petrified mud
C
A shell of a mollusc in a thick layer of calcium
D
A petrified human bone
Slide 3 - Quiz
An index fossil...
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0:20
A
is used as an indicator to see how old a layer is
B
is used as an indicator to see which layer has the most life forms
C
shows what a certain species looked like
D
Is the best-preserved fossil in a layer of rock
Slide 4 - Quiz
Explain why we do not
find fossils of bacteria.
find fossils of bacteria.
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1:00
Slide 5 - Open question
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Slide 10 - Video
How did the universe change, moments after the Big Bang?
A
It expanded and became hotter
B
It expanded and became cooler
C
It exploded and became hotter
D
It exploded and became cooler
Slide 11 - Quiz
Describe ancient Earth:
A
It had water and an atmosphere, but no oxygen
B
It had water and oxygen, but no atmosphere
C
It had water but no atmosphere, no oxygen
D
It had oxygen but no water and no atmosphere
Slide 12 - Quiz
Explain why the formation of the ozone layer was required for life to begin.
A
Ozone keeps the Earth at an optimal temperature
B
Ozone protects the Earth against harmful UV-radiation
