Two models currently exist as to the mechanism behind how glycoproteins and polysaccharides are processed and packaged in the Golgi apparatus. Which of the following statements is true in relation to at least one of these models?
A) Cargo molecules, having entered the cis-most cisterna, then progress through consecutive cisterna. In each cisterna the molecules are processed by enzymes specific to that cisterna. The number of cisternae the molecule is transported through is therefore directly proportional to the degree of modification it undergoes.
B) Cargo molecules move from one cisterna to the next in an anterograde direction via small vesicles. The processing enzymes that modify the cargo molecules remain in the same cisterna within the stack.
C) Processing enzymes move in a retrograde direction into only the first cisterna, with all subsequent movement external to cisternae and instead occuring via vesicles where processing enzymes are active.
D) Processing enzymes move freely between cisternae and vesicles where they come in to contact with cargo molecules moving from one cisternae to the next.
E) Vesicles and cisternae constantly fuse and divide, by which means they facilitate processing enzymes to contact and interact with cargo molecules as they move in either an anterograde or retrograde direction.

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The Answer of Two models currently exist as to the mechanism behind how glycoproteins and polysaccharides are processed and packaged in the Golgi apparatus. Which of the following statements is true in relation to at least one of these models?
A) Cargo molecules, having entered the cis-most cisterna, then progress through consecutive cisterna. In each cisterna the molecules are processed by enzymes specific to that cisterna. The number of cisternae the molecule is transported through is therefore directly proportional to the degree of modification it undergoes.
B) Cargo molecules move from one cisterna to the next in an anterograde direction via small vesicles. The processing enzymes that modify the cargo molecules remain in the same cisterna within the stack.
C) Processing enzymes move in a retrograde direction into only the first cisterna, with all subsequent movement external to cisternae and instead occuring via vesicles where processing enzymes are active.
D) Processing enzymes move freely between cisternae and vesicles where they come in to contact with cargo molecules moving from one cisternae to the next.
E) Vesicles and cisternae constantly fuse and divide, by which means they facilitate processing enzymes to contact and interact with cargo molecules as they move in either an anterograde or retrograde direction.

Two Models Currently Exist as to the Mechanism Behind How