The specific linkages between sugar rings, including the specific carbons that are linked together and the configuration of the linkage, are important for the properties of the polysaccharide;

           

          I) Amylose                          a) β(1,3)-linkages                               

        II) Cellulose                          b) β (1,4)-linkages

         III) Callose                                   c) α(1,4)-linked

                                                             d) α (1,3)-linkages

Which of the following linkage combinations is correct linkages of the polysaccharides?

#Question id: 10251

#Unit 6. System Physiology – Plant

Initial phase of glycolysis, substrates from different sources are channeled into triose phosphate. For each molecule of sucrose that is metabolized, four molecules of triose phosphate are formed. This process how much requires ATP input?

#Question id: 5541

#Unit 5. Developmental Biology

What is the valued average rate at which the human brain produces neurons during development?

#Question id: 15331

#Unit 4. Cell Communication and Cell Signaling

#Question id: 22944

#Unit 5. Developmental Biology

#Question id: 4108

#Unit 3. Fundamental Processes

The yeast Gal4 transcription activator comprises two domains: a DNA binding domain and an activation domain. The DNA-binding domain allows Gal4 to bind to appropriate DNA sequences located near genes that are required for metabolism of the sugar galactose. The activation domain binds to components of the transcriptional machinery (including RNA polymerase), attracting them to the promoter, so the regulated genes can be turned on. In the absence of Gal4, the galactose genes cannot be turned on. When Gal4 is expressed normally, the genes can be maximally activated. When Gal4 is massively overexpressed, however, the galactose genes are turned off. Choose correct explanation for this regulation?

A. In order for Gal4 to work properly, the DNA-bound Gal4 recruits many proteins, including RNA polymerase, to the promoter.

B. When there is too much Gal4 in the cell, the free and DNA-bound Gal4 will compete for the limited quantities of these other components.

C. In the presence of excess Gal4, those components are tied up in unproductive complexes with free Gal4, thereby preventing their recruitment to the promoter.

D. cells that massively overexpress Gal4 grow poorly because of the reduced availability of critical components of the transcription machinery.

E. Over concentration of Gal4 prevent suppressors to bind with DNA