Biology 121 – January 6
Measurements – documentation, data
Falling of leaves
Why do leaves fall?
3. Hypothesis – Phrasing of the question, at least 1, not to prove, goal is to disprove
one of the hypothesises
Decrease in nutrient levels
The decrease in temperature causes the falling of leaves.
The decrease in nutrient levels causes the falling of leaves.
The decrease in sunlight causes the falling of leaves.
The leaves will fall sooner in an environment with a lower temperature.
Set up 2 environments. One with a lower temperature and the other is in a
control group where the temperature
is mild. What causes algal blooms in lakes?
The conversion of a lake to a highly productive ecosystem with rapid decomposition, low
oxygen levels, and rapid filling with decomposing organic matter
Something, x, causes the algae to overgrow
When algae die, the bacteria decomposition increase CO2 increase
CO2 are toxic to fish
Lake is eutrophic – a dead lake, cannot support life
Thought phosphate caused the algae to overgrow
Question: what is the role of phosphate in algae growth?
o Increase in phosphate causes algal bloom.