What does it mean for a membrane to be selectively permeable?

Selective permeability is a property of cellular membranes that only allows certain molecules to enter or exit the cell. ... Movement across a selectively permeable membrane can occur actively or passively. For example, water molecules can move passively through small pores on the membrane.

b tumor cells have a cell wall instead of a membrane

explanation:

tumor cells different from normal cells because tumor cells have a cell wall instead of a membrane.

the sun's light combined with the visible wavelenghts form what is called ultraviolet radiation, which are the long waves at the end of a visible light sprectrum.

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