Protein degradation
30 Questions
1 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

Which of the following is a nonessential amino acid that can be made from a glycolytic intermediate?

  • Valine
  • Glycine
  • Alanine
  • Serine (correct)

Which enzyme is responsible for the conversion of 3-phosphoserine to serine?

  • Dehydrogenase
  • Phosphoserine phosphatase (correct)
  • Serine hydroxymethyltransferase
  • Aminopeptidase

Which amino acid can be made from serine?

  • Glycine (correct)
  • Valine
  • Leucine
  • Alanine

What is the primary use of amino acids in the body?

<p>Building blocks for protein synthesis (B)</p> Signup and view all the answers

What is the purpose of intracellular protein degradation?

<p>All of the above (D)</p> Signup and view all the answers

How can degrading proteins regulate biological and metabolic processes?

<p>All of the above (D)</p> Signup and view all the answers

Which of the following is true about protein degradation?

<p>Protein degradation can occur from the breakdown of ingested proteins or cellular proteins (A)</p> Signup and view all the answers

What is the recommended daily protein requirement for the average adult?

<p>0.8 g/kg of body weight (B)</p> Signup and view all the answers

What is nitrogen balance?

<p>The amount of nitrogen ingested is equal to the amount of nitrogen excreted (A)</p> Signup and view all the answers

When does a negative nitrogen balance occur?

<p>During starvation or physical trauma (A)</p> Signup and view all the answers

What is the chemical score used to assess in the protein quality of food?

<p>The ratio of essential amino acids in particular foods to the reference diet (B)</p> Signup and view all the answers

Why are some amino acids considered essential and must be obtained from the diet?

<p>Because they cannot be synthesized by the body (D)</p> Signup and view all the answers

Which organelle is responsible for the degradation of obsolete or unused proteins in the cytoplasm?

<p>Lysosome (B)</p> Signup and view all the answers

What is the function of the regulatory cap complex in the proteasome?

<p>To control access to the proteasomal interior (D)</p> Signup and view all the answers

Which enzyme type is responsible for removing ubiquitin from target proteins?

<p>Deubiquitinating enzyme (DUB) (C)</p> Signup and view all the answers

What is the pH range of lysosomes, where they function optimally?

<p>4-5 (C)</p> Signup and view all the answers

Which of the following diseases is NOT associated with proteins involved in the ubiquitin conjugating pathway?

<p>Multiple myeloma (A)</p> Signup and view all the answers

What is the first therapeutic proteasome inhibitor approved in the US for the treatment of relapsed multiple myeloma?

<p>VELCADE (bortezomib) (B)</p> Signup and view all the answers

Which of the following is true about protein degradation?

<p>Protein degradation allows the cell to maintain sensitivity to cellular signals. (B)</p> Signup and view all the answers

Which pathway is involved in the degradation of intracellular proteins?

<p>Ubiquitin-proteasome pathway (C)</p> Signup and view all the answers

What is the role of ubiquitin in protein degradation?

<p>Ubiquitin is a tag that marks proteins for destruction. (C)</p> Signup and view all the answers

What is the function of E3 in the ubiquitin-protein complex formation?

<p>E3 transfers ubiquitin from E2 to a lysine residue in the target protein. (B)</p> Signup and view all the answers

What is required for the degradation of a target protein?

<p>Polyubiquitination using K48 linkages within the ubiquitin protein. (A)</p> Signup and view all the answers

What happens to ubiquitin-tagged proteins in proteasomal degradation?

<p>They are degraded by the proteasome. (D)</p> Signup and view all the answers

Which of the following is NOT a source of amino acids for cellular metabolism?

<p>Essential amino acids (C)</p> Signup and view all the answers

What is the purpose of intracellular protein degradation?

<p>To regulate cholesterol biosynthesis (C)</p> Signup and view all the answers

Which pathway is responsible for the degradation of proteins through ubiquitin conjugation and proteasomal degradation?

<p>Ubiquitin-proteasome pathway (C)</p> Signup and view all the answers

What is the therapeutic role of proteasome inhibitors in the treatment of cancer?

<p>To induce apoptosis in cancer cells (B)</p> Signup and view all the answers

Which of the following is an example of lysosomal degradation of proteins?

<p>Autophagy (C)</p> Signup and view all the answers

What are two methods by which the protein quality of foods can be assessed?

<p>Dietary protein digestion and nitrogen balance (B)</p> Signup and view all the answers

More Like This

Use Quizgecko on...
Browser
Browser