C₄ cycle has been associated with a particular leaf structure, called Kranz anatomy, typical Kranz anatomy exhibits an inner ring of bundle sheath cells around vascular tissues and an outer layer of mesophyll cells. This particular leaf anatomy generates a diffusion barrier that is

 a.) separates the uptake of atmospheric carbon in mesophyll cells from CO2 assimilation by rubisco in bundle sheath cells

 b.) limits the leakage of CO2 from bundle sheath to mesophyll cells

 c.) diffusion gradients—not only between but also within the cells—guide the shuttling of metabolites between the two compartments that operate the C4 cycle

 d.)  Bundle sheath cells surround the vascular tissue, while an outer ring of mesophyll cells is peripheral to the bundle sheath and adjacent to intercellular spaces and the percolates metabolites are transfer to the whole plant cell by vascular tissue

 Find out the correct statements of Krantz anatomy

#Question id: 2831

#Unit 2. Cellular Organization

Specific DNA control elements in promoters can

a. interact with general transcription factors.

b. interact with repressor proteins.                 

c. interact with activator proteins.

d. remain unavailable because of condensed chromatin. 

#Question id: 2832

#Unit 2. Cellular Organization

Reporter genes are used to

a. express enzymes that are not easily assayed in cell extracts.

b. express enzymes that are easily assayed in cell extracts.

c. characterize DNA control elements.                     

d. characterize reporter plasmids.

#Question id: 2835

#Unit 2. Cellular Organization

An enhancer

a. can be located upstream of a promoter.

b. can be located downstream of a promoter.

c. can be located a variable distance from the promoter.

d. is always located within 1 kb of the promoter.

e. can be cell-type-specific.

#Question id: 2836

#Unit 2. Cellular Organization

#Question id: 2837

#Unit 2. Cellular Organization

#Question id: 2838

#Unit 2. Cellular Organization

You want to study the potential interaction between nucleosome-bound DNA and a specific histone deacetylase. You decide to perform an electrophoretic mobility shift assay (EMSA). You use a 32P end-labelled, linear template DNA that contains two nucleosome positioning sites. You assemble two nucleosomes on the DNA template before incubation with and without the histone deacetylase. For some reactions, you use unmodified nucleosomes. For other reactions, you use nucleosomes that are methylated at lysine 36 of the histone protein H3.

A. The histone deacetylase binds nucleosome bound-DNA in lanes 1, 2, 3, and 4.

B. The histone deacetylase binds nucleosome bound-DNA in lanes 3& 4.

C. The histone deacetylase seems to recognize methylated nucleosomes at lysine 36 of histone H3 in lane 1, 2 & 3 better than unmethylated nucleosomes in lane 4 &5

D. The histone deacetylase seems to recognize methylated nucleosomes at lysine 36 of histone H3 in lane 1 & 2 better than unmethylated nucleosomes in lane 3 &4