Answer:the possession of feathers
Explanation:birds are warm blooded animals , that possess feathers.these feathers cover their bodies and used for flight and warmth.their forelimbs are modified into wings,which fold into a Z shape at rest.feathers grow from the skin follicles and are replaced by scales on their legs.they possess oil gland to dress the feathers.
Other features of birds include
1) beaks with no teeth
2) fully ossified bones with air cavities
3)females with left ovary and oviducts only
The number of species on Earth tagged at 8.7 million as of 2011.
It is the total mass of organisms in the given area
The most likely thing that happened with this poor young woman who broke her leg was that she broke hte bone at a very young age and that it fully healed. C
This is so because collagen is a substance that gets secreted at the point of fracture which helps strengthen the bone. Having a higher amount of collagen at the site of a broken bone means that the bone probably healed properly and there was a remainder of collagen to be found.
Essentially the answer is in the names. Active transport requires energy to facilitate to movement of the materials while passive transport is something like osmosis which is when the material moves based on concentration in an effort to create equality between the two sides. Basically passive is when the materials move under the own power.
