Mold is a living organism, therefore it is biotic.
Answer:
a substance that has a ph level less than 7
Explanation:
These global wind systems, in turn, drive the oceans' surface currents. Unequal heating of the Earth's surface also forms large global wind patterns. In area near the equator, the sun is almost directly overhead for most of the year. Warm air rises at the equator and moves toward the poles ((from google))
<u>Answer:</u>
Recent evidence suggest that feathers evolved from scales and suggest that 'feathers and pycnofibers' could be homologous.
<u>Explanation:</u>
- One of the major difficult issue related to bird evolution is the evolution of feathers.
- Feathers are considered as the most 'complex integumentary structures' which are found in vertebrates.
- Evolutionary developmental biology suggests that the 'planar scale structure' is been modified for developing into feathers by 'splitting' to form web like structures.
- Scales and Feathers consist of 'two distinct form of keratin' so it was thought that 'each type was exclusive skin structure' but recent study suggests that they are developmental expressions of same skin structures.
<span>There are no choices given, but the event was most likely a physical one that would have barred the squirrels from seeing each other. Squirrels are a social creature, and the event that would have separated the populace could have been anything from a large fire to an earthquake that separated the squirrels from each other.</span>