TLS Online TPP Program

#Question id: 11145


Two fundamental concepts about the ion channels of a "resting" neuron are that the channels ________.

#XL - T Zoology
  1. are always open, but the concentration gradients of ions frequently change
  2. are always closed, but ions move closer to the channels during excitation
  3. are open or closed depending on their type, and are specific as to which ion can traverse them
  4. open in response to stimuli, and then close simultaneously, in unison
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TLS Online TPP Program

#Question id: 9616

#XL - S Microbiology

Which mutation should least require realignment of homologous regions of a gene that is common to several related species?

TLS Online TPP Program

#Question id: 9616

#XL - R Botany

Which mutation should least require realignment of homologous regions of a gene that is common to several related species?

TLS Online TPP Program

#Question id: 9617

#XL - S Microbiology

The common ancestors of birds and mammals were very early (stem) reptiles, which almost certainly possessed 3-chambered hearts (2 atria, 1 ventricle). Birds and mammals, however, are alike in having 4-chambered hearts (2 atria, 2 ventricles). The 4-chambered hearts of birds and mammals are best described as

TLS Online TPP Program

#Question id: 9617

#XL - R Botany

The common ancestors of birds and mammals were very early (stem) reptiles, which almost certainly possessed 3-chambered hearts (2 atria, 1 ventricle). Birds and mammals, however, are alike in having 4-chambered hearts (2 atria, 2 ventricles). The 4-chambered hearts of birds and mammals are best described as

TLS Online TPP Program

#Question id: 9618

#XL - S Microbiology

Generally, within a lineage, the largest number of shared derived characters should be found among two organisms that are members of the same

TLS Online TPP Program

#Question id: 9618

#XL - R Botany

Generally, within a lineage, the largest number of shared derived characters should be found among two organisms that are members of the same