Glucose, labeled with 14c in different carbon atoms, is added to a crude extract of a tissue rich in enzymes of the pentose phosphate pathway. the most rapid production of 14co2 will occur when the glucose is labeled in:
a. c-1
b. c-3
c. c-4
d. c-5
e. c-6

A. C-1

Explanation:

During the pentose phosphate pathway, glucose 6-phosphate is first converted into 6-phosphoglucono-lactone in the reaction catalyzed by glucose 6-phosphate dehydrogenase. The 6-phosphoglucono-lactone is then converted into 6-phospho-gluconate which in turn undergoes decarboxylation to form D-ribulose 5-phosphate and the C-1 of original glucose 6-phosphate is released in form of CO2.  

Therefore, to observe the most rapid production of labeled carbon atom in form of CO2, the C-1 of glucose should be labeled.

increase soil erosion                                             reduce soil erosion

cattle grazing                                                         hydroseeding

deforestation                                                         contour plowing

                                                                                planting vegetation

plant roots basically hold the top soil

together and stop soil erosion because

in such situation top soil is not removed

during flood but cattle grazing causes

soil erosion because cattle consume the

grasses and herbs and top soil is exposed.

same situation occurs because of

deforestation, the trees and plants are cut

down to expose top soil which causes soil

erosion