CourseCourseConceptConceptDocsDocuments

IB Biology HL D3.2.7 Phenylketonuria Pku Questions

Connect the autosomal-recessive PKU genotype to PAH deficiency, then evaluate treatment evidence and THB advantages in IB Biology HL D3.2.7.

Syllabus
First assessment 2025
Course
Biology HL
Level
HL

Exam points

  • Identify the autosomal-recessive PKU genotype and connect PAH deficiency with phenylalanine accumulation and the resulting condition.
  • Evaluate treatment evidence for PKU by weighing phenylalanine-level changes and limitations, and compare THB with protein-restricted treatment.

Learn this topic

Study D3.2.7—Phenylketonuria (PKU) conceptsOpen the corresponding Concept lesson for explanations, examples and exam connections.

IB Biology HL D3.2.7 Phenylketonuria Pku Questions question 1

[Maximum number: 1]

The table summarizes the relative content of essential amino acids in different foods. Cysteine and tyrosine are classified as being "conditionally essential". The quantity of each amino acid in a hen egg is set as 1.0 and all other values are relative to the hen egg standard.

Table for Question IB Biology HL D3.2.7 Phenylketonuria Pku Questions question 1 — IB Biology HL

Phenylalanine is converted to tyrosine by the enzyme phenylalanine hydroxylase.

Figure for Question IB Biology HL D3.2.7 Phenylketonuria Pku Questions question 1 — IB Biology HL

When infants with the condition phenylketonuria (PKU) are left untreated, they have a build-up of phenylalanine in the blood and high levels of phenylalanine in the urine. State the cause of this condition.

All question bank results loaded