Answer:
Every winter, Arctic sea ice grows around the pole, its frozen tendrils threading along northern coasts. Right now sea ice has just passed its peak coverage for the year, and will begin to shrink with the coming of spring. It’s a crucial time for polar bears, whose food supply is inextricably linked to sea ice.
And in recent decades, sea ice has been shrinking faster than ever. According to the National Snow and Ice Data Center, 2019 has the seventh-lowest sea ice cover in the Arctic since they began collecting satellite data 40 years ago.
This year “doesn't break any records, but it's the trend that matters,” says University of Alberta polar bear scientist Andrew Derocher. “The downward trend in Arctic sea ice across all months is the concern,” he says, and “now we wait to see what spring conditions bring.” (Read more about global warming’s link to polar bears.)
A cold spring allows ice to linger, giving polar bears easier access to one of their favorite foods: seals. A warm spring cuts short the availability of their food super-highway....
The bird fossil Archaeopteryx is a species linking dinosaurs and birds.
Meristem at the tips of stems and roots produce rapid growth in plants. Meristem is a tissue that is mostly found in plants. Meristematic cells are responsible for the plant's rise and to keep the plant growing.
If you are going from a high gradient to a low gradient it’s passive transport. Think of a hill if you put a rock at the top of that hill it will go down no energy involved. Active transport is going up the hill you must use energy to push that rock up the hill because it’s from a low gradient to the top. Hope this helps
