Question

the diagram shows four pairs of chromosomes from the karyotype of a normal human male. select the pair of sex chromosomes.

Explanation:

Step1: Recall sex chromosomes in males

Human males have sex chromosomes \(XY\), where the \(X\) and \(Y\) chromosomes differ in size and shape (the \(Y\) is smaller and has a different structure than \(X\)).

Step2: Analyze each pair

• First pair: Both chromosomes look similar (likely autosomes or \(XX\) - not male sex chromosomes).
• Second pair: Both look similar (not \(XY\)).
• Third pair: Both look similar (like \(XX\) - female sex chromosomes or autosomes).
• Fourth pair: One chromosome is larger ( \(X\)) and one is smaller ( \(Y\) ), matching the male \(XY\) sex chromosome pair.

Answer:

The Fourth Graph (the bottom - most pair of chromosomes)