Practice Questions

  1. Home
  2. Free Resources
  3. Practice Questions
  4. 54777
TLS Online TPP Program

#Question id: 739

What is true about the rotation about bonds in a protein backbone?

#Unit 1. Molecules and their Interaction Relevant to Biology

  1. The rotation is free about all bonds in the backbone, except for the bond between the nitrogen and the alpha carbon in proline residues.

  2. The bond between the carbonyl carbon and nitrogen is restricted. Other bonds are free to rotate depending only on steric hindrance or the presence of proline residues.

  3. All bonds in the backbone have restricted rotation and partial double-bond character.

  4. The rotation is free only about the peptide bond. The other bonds are restricted by steric hindrance and the presence of proline residues.

More Questions
TLS Online TPP Program

#Question id: 15735

#Unit 12. Applied Biology

How meristem cultures are able to generate pathogen free plants. Choose the most appropriate statement.
TLS Online TPP Program

#Question id: 14740

#Unit 4. Cell Communication and Cell Signaling

Rod cells sense light with the aid of a light-sensitive GPCR known as rhodopsin; choose incorrect statements
a. Rhodopsin consists of the protein opsin, which has the usual seven–transmembrane segment GPCR structure, covalently linked to a light-absorbing pigment called retinal. 
b. Rhodopsin, found only in rod cells, is localized to the thousand or so flattened membrane disks that make up the inner segment of each of these rod-shaped cells.
c. A human rod cell contains about 4 × 107 molecules of rhodopsin. 
d. The heterotrimeric G protein coupled to rhodopsin, called transducin (Gt), contains a Gα unit referred to as Gαt; like rhodopsin, Gαt is found only in rod cells.
TLS Online TPP Program

#Question id: 4970

#Unit 11. Evolution and Behavior

If two continental land masses converge and are united, then the collision should cause
TLS Online TPP Program

#Question id: 12954

#Unit 7. System Physiology – Animal

A 55-year-old male patient with hypertension has had his blood pressure reasonably well controlled by administration of a thiazide diuretic. During his last visit (6 months ago) his blood pressure was 130/75 mm Hg and his serum creatinine was 1 mg/100 ml. He has been exercising regularly for the past 2 years, but recently has complained of knee pain and began taking large amounts of a nonsteroidal anti-inflammatory drug. When he arrives at your office, his blood pressure is 155/85 and his serum creatinine is now 2.5 mg/100 ml. Which of the following best explains his increased serum creatinine?
TLS Online TPP Program

#Question id: 11020

#Unit 7. System Physiology – Animal

Circus movements in the ventricle can lead to ventricular fibrillation. Which of the following conditions in the ventricular muscle will increase the tendency for circus movements?