Practice Questions

  1. Home
  2. Free Resources
  3. Practice Questions
  4. 54863
TLS Online TPP Program

#Question id: 899

Which statement is true about disulfide bonds and protein folding?

#Unit 1. Molecules and their Interaction Relevant to Biology

  1. Disulfide bonds have no influence on protein folding since they only form after the protein adopts its native conformation.

  2. Proteins occasionally adopt nonnative conformations and form improper disulfide bonds that can be reversed by the enzyme protein disulfide isomerase.

  3. The folding of the native conformation is influenced more strongly by the formation of disulfide bonds than by the primary structure of a protein.

  4. If a protein forms an improper disulfide bond it is irreversibly inactivated and must be

More Questions
TLS Online TPP Program

#Question id: 13168

#Unit 10. Ecological Principles

Use the following diagram from the text showing the spread of the cattle egret, Bulbulcus ibis, since its arrival in the New World, to answer the following question.


How would an ecologist likely explain the expansion of the cattle egret?
TLS Online TPP Program

#Question id: 13022

#Unit 10. Ecological Principles

A certain species of pine tree survives only in scattered locations at elevations above 2,800 m in the western United States. To understand why this tree grows only in these specific places an ecologist should
TLS Online TPP Program

#Question id: 13020

#Unit 10. Ecological Principles

Experts in deer ecology generally agree that population sizes of deer that live in temperate climates are limited by winter snow. The deer congregate in ?yarding? areas under evergreen trees because venturing out to feed in winter is energetically too expensive when snowfall depths accumulate to above 40 cm. Deer often stay yarded until the spring thaw. Snow depth over 40 inches for more than 60 days results in high mortality due to starvation.  This observation best illustrates which of the following principles about factors that limit distribution of organisms?
TLS Online TPP Program

#Question id: 13019

#Unit 10. Ecological Principles

Air masses formed over the Pacific Ocean are moved by prevailing westerlies where they encounter extensive north- south mountain ranges, such as the Sierra Nevada and the Cascades. Which statement best describes the changes that these air masses undergo?
TLS Online TPP Program

#Question id: 13018

#Unit 10. Ecological Principles

Generalized global air circulation and precipitation patterns are caused by
TLS Online TPP Program

#Question id: 13017

#Unit 10. Ecological Principles

Which of the following statements best describes the effect of climate on biome distribution?