Birds have hollow bones due to the fact thay need to be as light as possible for their wings to generate enough lift for them to fly
Answer:
Sometimes, chemical weathering dissolves large portions of limestone or other rock on the surface of the Earth to form a landscape called karst. In these areas, the surface rock is pockmarked with holes, sinkholes, and caves. The water transforms anhydrite into gypsum, one of the most common minerals on Earth.
Explanation:
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Answer:
The answer is D.) Mercury
The right answer is facilitated diffusion.
Facilitated diffusion is a diffusion mechanism facilitated by membrane transporters. it's the spontaneous passage of molecules or ions (like the passive diffusion) through a biological membrane through transport molecules (unlike passive diffusion). This process does not consume energy (like the passive diffusion) and therefore does not involve active transportation.
