Primary Structure of Proteins — Flashcards

Flashcard 1: Which structure of protein is the most common and most stable?_____

Answer: alpha helix

Flashcard 2: C1-inhibitor (C1 INH) is the largest member of the _____ superfamily of proteins.

Answer: serpin

Flashcard 3: Elastin is rich in non-hydroxylated _____, glycine, and lysine residues (amino acids)

Answer: proline

Flashcard 4: What is the stabilizing bond in primary protein structure?_____

Answer: peptide bond

Flashcard 5: The given image represents a _____ which is a secondary structure of proteins.

Answer: beta-sheet

Flashcard 6: The direction of protein synthesis is _____-terminus to C-terminus

Answer: N

Flashcard 7: Curve A indicates which compound? _____

Answer: Myoglobin

Flashcard 8: egg white forms _____% weight of egg

Answer: 60

Extra: 

Flashcard 9: Serum _____ is the most sensitive indicator for protein estimation (nutritional status).

Answer: pre-albumin

Extra: • **Pre-albumin (Transthyretin):** Most sensitive indicator (Half-life ≈ 2 days). • **Albumin:** Indicator of chronic nutritional status (Half-life ≈ 20 days). • **Retinol-binding protein:** Even shorter half-life (~12 hours) but less commonly tested. Note: Albumin is a negative acute-phase reactant, meaning its levels drop during inflammation regardless of nutritional status.