TLS Online TPP Program

#Question id: 15617


Wild type E. coli metabolizes the sugar lactose by expressing the enzyme ß-galactosidase. You have isolated a mutant that you call lac1–, which cannot synthesize ß-galactosidase and cannot grow on lactose (Lac–). During an condition you have a wild type (Lac+) strain carrying a Tn5 insertion known to be near several Lac genes on the E. coli chromosome. You grow P1 phage on this strain and use the resulting phage lysate to infect the lac1– strain, selecting for kanamycin resistance (Kanr). Among 100 Kanr transductants, you find that 82 are Lac– and 18 are Lac+. Express the distance between Tn5 and the lac1– mutation as a cotransduction frequency;

#SCPH01 Biochemistry
  1. 23%
  2.  18%
  3. 82%
  4. 16%
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TLS Online TPP Program

#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?


TLS Online TPP Program

#Question id: 11073

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

The respiratory passageways have smooth muscle in their walls. Which of the following best describes the effect of acetylcholine and epinephrine on the respiratory passageways?

TLS Online TPP Program

#Question id: 11073

#SCPH28 | Zoology

The respiratory passageways have smooth muscle in their walls. Which of the following best describes the effect of acetylcholine and epinephrine on the respiratory passageways?

TLS Online TPP Program

#Question id: 11074

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

A 30-year-old woman performs a valsalva maneuver about 30 min after eating lunch. Which of the following best describes the changes in pulmonary and systemic blood volumes that occur in this woman?


TLS Online TPP Program

#Question id: 11074

#SCPH28 | Zoology

A 30-year-old woman performs a valsalva maneuver about 30 min after eating lunch. Which of the following best describes the changes in pulmonary and systemic blood volumes that occur in this woman?


TLS Online TPP Program

#Question id: 11075

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

A 65-year-old man with emphysema due to 34 years of cigarette smoking is admitted to hospital due to dyspnea. With further tests the mean pulmonary arterial pressure is determined to be 45 mm Hg at rest. He is hypoxic (PO2 = 49 mm Hg), hypercapnic (85 mm Hg), and slightly acidotic. The cardiovascular and oxygen changes are due to which of the following?