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.              

From these experiments,  Classify  the  gln2– and gln3– mutations in terms of their basic genetic properties explaining the rationale behind your conclusions. Based on these properties make a proposal for the types of regulatory functions affected by the gln2– and gln3– mutations.

#Question id: 11069

#SCPH28 | Zoology

A 22-year-old woman inhales as much air as possible and exhales as much air as she can producing the spirogram shown in the figure. A residual volume of 1.0 L was determined using the helium dilution technique. What is her functional residual capacity (in liters)?

#Question id: 11070

#I Life Science/ Life Sciences Group – I-V

A patient has a dead space of 150 ml, functional residual capacity of 3 L, tidal volume of 650 ml, expiratory reserve volume of 1.5 L, a total lung capacity of 8 L, respiratory rate of 15 breaths/min. What is the alveolar ventilation?

#Question id: 11070

#SCPH28 | Zoology

A patient has a dead space of 150 ml, functional residual capacity of 3 L, tidal volume of 650 ml, expiratory reserve volume of 1.5 L, a total lung capacity of 8 L, respiratory rate of 15 breaths/min. What is the alveolar ventilation?

#Question id: 11071

#SCPH28 | Zoology

At the end of inhalation, with an open glottis, the pleural pressure is

#Question id: 11072

#I Life Science/ Life Sciences Group – I-V

The following diagram shows pulmonary airway resistance expressed as a function of pulmonary volume. Which relationship best describes the normal lung?

#Question id: 11072

#SCPH28 | Zoology

The following diagram shows pulmonary airway resistance expressed as a function of pulmonary volume. Which relationship best describes the normal lung?