Why is high fitness a function of an organism’s environment? Include animals from a specific environment, such as the polar bear in the arctic tundra, as evidence to support your explanation. Please help

When water freezes, it . contracts expands

What are the doorways into and out of cells, attached to the membrane, and built in the rough er.

Nucleus has two lobes; contains granules of lysosomal enzymes; functions in attacking parasitic worms and plays complex roles in inflammatory diseases like allergies and asthma. what blood cells are described?