cell membrane

Question 1

phospholipid bilayer

Answer 1

hydrophilic head faces outwards

hydrophobic tail faces inwards

Question 2

cholesterol

Answer 2

hydrophobic (embedded within membrane)

provides structural support

Question 3

carrier proteins

Answer 3

intrinsic
bind to large molecules, and change shape to carry the molecule across the bilayer
requires ATP

Question 4

channel proteins

Answer 4

intrinsic
water-filled tubes which allow water-soluble ions to diffuse across the bilayer
requires polar molecules

Question 5

glycolipid

Answer 5

extrinsic
cell-surface receptor for some chemicals
allows cells to attach to each other (tissue formation)

Question 6

glycoprotein

Answer 6

extrinsic
cell-surface receptor for hormones and neurotransmitters
allows cell recognition (immune system)