Sample Quiz

The cell wall component _____ forms the structural base, acting like rebar.

A:Cellulose

The cell wall component _____ acts like a glue to hold together other components & adjacent cells.

A:Pectin

The cell wall component ____ is only found in the secondary cell wall & is the basis of

wood.

A:

Lignin

T/F - Hemicellulose is deposited as unbranched fibers whose orientation influences the

direction of cell expansion.

A:

False - Cellulose instead of hemicellulose

Explanation: Hemicellulose is branched in structure & cross-links cellulose fibers to

increase the strength of the cell wall

T/F - Cell expansion is an unregulated process dictated by the amount of water in the cell

A:

False - Cell expansion is a regulated process. It is heavily influenced by the amount of

water in the cell, but also through active processes like acidification of the cell wall &

expansin activity & passively via the orientation of cellulose fibers.

Which of the following is

NOT

a way that the cell wall can participate in signaling?

A.

Wall fragments can serve as defense or developmental cues

B.

Expansins selectively blocking molecules from passing through the cell wall

C.

Forming plasmodesmata to increase cytoplasm connection

D.

Porous nature allows molecules to pass through