You are studying regulation of the yeast enzyme glutamine synthetase (GS), which is encoded by the GLN1 gene. You have isolated two mutants, designated gln2– and gln3–, that give decreased GS activity. Mating of either gln2– or gln3– haploids to wild type produces heterozygous diploids that show normal amounts of GS expression. When you cross either a gln2– or gln3– haploid to a gln1– strain the resulting diploids show normal expression of GS.              

How many units of ß-galactiosidase would you expect to be expressed from deletion 1 in a gln2– mutant? 

TLS Online TPP Program

#Question id: 28760

#Unit 2. Cellular Organization

Pex5 is a receptor which binds with peroxisomal-targeting sequence proteins in the cytosol that protein targeted into the peroxisomal matrix by forming a multimeric complex with the Pex14 receptor located on the peroxisomal membrane. After assembly, the matrix protein dissociates from Pex5 and Pex5 is then returned to the cytosol by which process?

TLS Online TPP Program

#Question id: 28761

#Unit 2. Cellular Organization

Which of the following characteristics are TRUE for Lysosomes ?

a) Is a membrane-enclosed organelles

b) Is Filled with hydrolytic enzymes all are acid hydrolases 

c) Acid hydrolases they need to be activated by proteolytic cleavage

d) Work best at acidic pH

TLS Online TPP Program

#Question id: 28762

#Unit 2. Cellular Organization

For optimal activity, of lysosomal acid hydrolases they need to be___

a)Activation based on sensitivity to cleavage by endoglycosidase-D

b)Activation by proteolytic cleavage

c)Requires an acid environment

TLS Online TPP Program

#Question id: 28763

#Unit 2. Cellular Organization

Lysosome an interior pH of about_____

TLS Online TPP Program

#Question id: 28764

#Unit 2. Cellular Organization

Which of the following organelles membrane proteins, are highly glycosylated in compared to other organelles, which helps to protect them from the proteases?

TLS Online TPP Program

#Question id: 28765

#Unit 2. Cellular Organization

Which class of H+ ATPase in the lysosomal membrane, pumps H+ into the lysosome and maintaining its lumen at an acidic pH?