Answer:
The Earth is essentially a closed system; it obtains lots of energy from the Sun but the exchange of matter with the outside is almost zero. Isolated systems can exchange neither energy nor matter with an outside system.
The Precambrian was originally defined as the era that predated the emergence of life in the Cambrian Period. It is now known, however, that life on Earth began by the early Archean and that fossilized organisms became more and more abundant throughout Precambrian time.
1 out of 5 is 1/5.
Divide that and you get .20, which is 20%, so that is your answer, 20% fat.
<em>When water is abundant:</em>
-Temporal regulation of stomata is used:
Open during the day
Closed at night
- At night, there is no photosynthesis, so no demand for CO2 inside the leaf.
- Sunny day = demand for CO2 in leaf is high = stomata wide open.
- As there is plenty of water, plant trades water loss for photosynthesis products.
- If the leaf's CO2 concentration is low, the stomata will stay open to continue fueling photosynthesis.
- High temperatures will also signal stomata to close.
- When limited water is available in the soil, plants try to prevent water loss.
