Question

gy 25.26 sa unit 2 cell structure, function & transport - school
some molecules are too big to pass through the phospholipid bilayer of the cell membrane. these molecules need to pass through proteins that are embedded in the cell membrane.
oa proteins
ob ribosomes
oc cell wall
od carbohydrates

Explanation:

The cell membrane has a phospholipid bilayer. Some molecules need help to pass through it. Proteins embedded in the cell - membrane can act as channels or carriers for such molecules to cross the membrane. Ribosomes are involved in protein synthesis and are not part of the membrane - crossing mechanism. The cell wall is a rigid outer layer in plant cells and not related to the passage of molecules through the phospholipid bilayer. Carbohydrates on the cell membrane are mainly for cell - cell recognition and not for facilitating molecule passage through the bilayer.

Answer:

A. proteins