Semipermeable membrane

Glioblastoma multiforme (GBM) is a type of malignant brain tumor typically found in the cerebral hemispheres, but can be found anywhere in the brain or spinal cord. These tumors are highly malignant meaning a large number of cells reproduce at any given time. There are two main types: primary, or de novo meaning the tumors make themselves known quickly and are extremely aggressive, and secondary meaning the tumors have a slower growth history but are equally aggressive . Secondary tumors are…

As a rule, the gill area is greater in fast-moving crabs (Portunids) than in sluggish bottom dwellers; decreases progressively from wholly aquatic, to intertidal, to land species; and is greater in young crabs than in older crabs. Often the gills are enclosed in protective chambers, and ventilation is provided by specialized appendages that create the respiratory current. As in cephalopod mollusks, oxygen utilization is relatively high—up to 70 percent of the oxygen is extracted from the water…