L14 Plant cell wall structures and function

Which of these is not an industrial use of the plant cell wall?

Choose the incorrect statement about the cell wall/plant cells.

Cellulose is: (Choose all correct.)

Cellulose forms microfibrils which contain hydrogen bonds.

Choose the incorrect statement about the primary cell wall.

Pectin: (Choose all correct.)

There are [blank_start]two[blank_end] phases of cell wall composition, plus a network of [blank_start]extensin[blank_end]. Firstly, a [blank_start]crystalline microfibrillar phase[blank_end] where cellulose is the main component. Secondly, a [blank_start]non-crystalline matrix[blank_end] is formed of pectic [blank_start]polysaccharides[blank_end] and [blank_start]hemicellulosic[blank_end] polysaccharides. Hemicellulose is a [blank_start]heterogenous[blank_end] polysaccharide, with a [blank_start]single[blank_end] sugar backbone, containing short [blank_start]side[blank_end] chains of different sugars. It forms a rigid structure. Pectin is a [blank_start]branched[blank_end] and negatively charged polysaccharide.

Which of these is not an effect of extensin and cellulose cross linking.

Complete the steps of cell wall synthesis. 1. [blank_start]Cellulose microfibrils[blank_end] are made and excreted by the [blank_start]plasma membrane[blank_end] to form the cell wall basis. 2. [blank_start]Polysaccharides pectin and hemicellulose[blank_end] are processed/fully synthesized in the [blank_start]Golgi[blank_end] and leave in vesicles to the cell wall. 3. [blank_start]Proteins e.g. extensins[blank_end] from the [blank_start]rough endoplasmic reticulum[blank_end] go through the Golgi and are sent to added the cell wall via vesicles. Note: all vesicles fuse to the plasma membrane.

Cellulose is synthesized by a multi sub unit complex, which contains the enzyme [blank_start]cellulose synthase[blank_end]. Sucrose is spilt into it's components of [blank_start]sucrose[blank_end] and glucose. Glucose is used to make [blank_start]cellulose[blank_end] while sucrose remains in the [blank_start]cytosol[blank_end].

Choose the incorrect statement about the cell wall synthesis process.

Randomly oriented cellulose microfibrils causes the cell to expand in all directions.

Microfibrils perpendicular to the long axis of the cell will cause the cell to expand horizontally.

Infected cells will produce:

When cells receive a signal from an adjacent infected cell, they will:

Choose the correct statement about the secondary cell wall.

The secondary cell wall:

Choose the correct statements about the secondary cell wall.

Lignin is found in [blank_start]secondary[blank_end] cell walls and is the [blank_start]second most[blank_end] abundant macromolecule on earth. It is a complex phenolic [blank_start]polymer[blank_end] which confers strength, [blank_start]rigidity[blank_end] and [blank_start]hydrophobicity[blank_end].

A grouping of plasmodesmata is called a:

Plasmodesmata allow cell to cell [blank_start]communication[blank_end] via channels which connect [blank_start]cytoplasm[blank_end]. The plasma membrane around these pores is [blank_start]continuous[blank_end] from one cell to another. The plasmodesmata are small enough to prevent [blank_start]organelle[blank_end] movement but large enough to allow the free exchange of [blank_start]small molecules[blank_end]. The endoplasmic reticulum can [blank_start]penetrates[blank_end] the plasmodesmata to [blank_start]bridge[blank_end] between cells.

Choose the correct options.