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TLS Online TPP Program

#Question id: 179

The average molecular weight of the 20 standard amino acids is 138, but biochemists use 110 when estimating the number of amino acids in a protein of known molecular weight.  Why?

#Unit 1. Molecules and their Interaction Relevant to Biology

  1. The number 110 is based on the fact that the average molecular weight of a protein is 110,000 with an average of 1,000 amino acids.

  2. The number 110 reflects the higher proportion of small amino acids in proteins, as well as the loss of water when the peptide bond forms.

  3. The number 110 reflects the number of amino acids found in the typical small protein, and only small proteins have their molecular weight estimated this way.

  4. The number 110 takes into account the relatively small size of nonstandard amino acids.

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TLS Online TPP Program

#Question id: 14863

#Unit 6. System Physiology – Plant

Plant and fungal plasma membrane H+-ATPases and Ca2+-ATPases are members of a class known as P-type ATPases, which are phosphorylated as part of the catalytic cycle that hydrolyzes ATP. Because of this phosphorylation step, the plasma membrane ATPases are strongly inhibited by
TLS Online TPP Program

#Question id: 14864

#Unit 6. System Physiology – Plant

Which of the following statements of ATPase is INCORRECT?
TLS Online TPP Program

#Question id: 14880

#Unit 4. Cell Communication and Cell Signaling

Which of the following cells control the differentiation HSCs (hematopoietic stem cells)?
TLS Online TPP Program

#Question id: 14881

#Unit 4. Cell Communication and Cell Signaling

The paradigmatic adult stem cell niche, contains several cell types that coordinate HSC development, including in column I and column II
TLS Online TPP Program

#Question id: 14882

#Unit 4. Cell Communication and Cell Signaling

In bone marrow, stem cells are committed to different lineages. Factors that stimulate colonies of these different lineages are interleukin-3 (multi-CSF), IL-7,  granulocyte- macrophage colony stimulating factor (GM-CSF) and granulocyte or macrophage colony- stimulating factor (G-CSF or M-CSF). In a mouse deficient in IL-7 the number of which cells will not be altered
TLS Online TPP Program

#Question id: 14883

#Unit 4. Cell Communication and Cell Signaling

Where is double negative selection is found during T-cell formation?