d . semilayer
7 . The nucleus is surrounded by a double layer membrane called the Nuclear Envelope .
a . nuclear matrix
b . nuclear envelope
c . cell membrane
d . nucleus wall
8 . Not all substances can cross the cell membrane , for this reason , the cell membrane is said to be
a . a barrier
b . selectively permeable
c . membrane bound
d . a cell wall
9 . The cell organelle that processes and packages for export substances produced by the cell is
a . mitochondria
b . ribosomes
c . Golgi apparatus
d . ER