There's been a lot of bad news for polar bears recently. In 2007, for example, scientists reported that if global warming continues unabated, the population could drop two-thirds by 2050.
Cell transport is useful because it's, essentially, the movement of cells across the blood/veins. Active transport uses energy, while passive transport does not.
Light is a form of EM radiation.
EM radiation has no mass (it's just energy packets called photons).
EM radiation can travel through a vacuum. (The speed of light in a vacuum is called c and is around 300,000 m/s).
Hope this helps!
<span>It may be safe to say that we can rule out a concussion for this patient. The CT scan is negative for trauma to the skull, brain bleed and negative for tumors. However, there is a slight abnormality regarding the smaller size of the ventricles but otherwise unremarkable.</span>
