TLS Online TPP Program

#Question id: 31406


The functions of tropomyosin in skeletal muscle include;

#Unit 2. Cellular Organization
  1. sliding on actin to produce shortening.
  2. releasing Ca2+ after initiation of contraction.
  3. binding to myosin during contraction.
  4. acting as a “relaxing protein” at rest by covering up the sites where myosin binds to actin.
More Questions
TLS Online TPP Program

#Question id: 30104

#Unit 1. Molecules and their Interaction Relevant to Biology

A nucleoside phosphorylase:

1. cleaves a nucleoside with the production of ribose 1-phosphate.
2. is necessary for the major salvage pathway for pyrimidines.
3. is used in the degradation of purine nucleotides.
4. is responsible for the equilibration of nucleoside monophosphates and nucleoside diphosphate.

TLS Online TPP Program

#Question id: 30105

#Unit 1. Molecules and their Interaction Relevant to Biology

Methotrexate is an inhibitor of dihydrofolate reductase. Administration of methotrexate would inhibit:
1. de novo synthesis of UMP.
2. conversion of dUMP to dTMP.
3. conversion of IMP to GMP.
4. de novo synthesis of IMP

TLS Online TPP Program

#Question id: 30106

#Unit 1. Molecules and their Interaction Relevant to Biology

If a cell has an adequate supply of adenine nucleotides but requires more guanine nucleotides for protein synthesis:

1. Glutamine-PRPP amidotransferase will not be fully inhibited.
2. AMP will be a feedback inhibitor of the condensation of IMP with aspartate.
3. ATP will stimulate the production of GMP from IMP.
4. ATP will inhibit nucleoside diphosphate reductase.

TLS Online TPP Program

#Question id: 30107

#Unit 1. Molecules and their Interaction Relevant to Biology

Major controls of de novo AMP synthesis include:

1. allosteric inhibition by GMP.
2. allosteric inhibition by AMP.
3. availability of PRPP.
4. stimulation by GTP.

TLS Online TPP Program

#Question id: 30108

#Unit 1. Molecules and their Interaction Relevant to Biology

Aspartate plays a role in all of the following EXCEPT:

TLS Online TPP Program

#Question id: 30109

#Unit 1. Molecules and their Interaction Relevant to Biology

Allopurinol is an inhibitor of xanthine oxidase. Administration of allopurinol to a patient with gout and normal HG-PRT levels would be expected to lead to all of the following EXCEPT: