[Campbell Biology P.1114] Suppose you discovered two distinct classes of mouse mutations: one... | Practice Question

Suppose you discovered two distinct classes of mouse mutations: one class exclusively affects limb development, while the other affects both limb and kidney development. Based on the concept of positional information and the text's implications regarding developmental processes, which class of mutation would be more likely to alter the function of monocilia?

  • option_a: The class affecting only limb development, as monocilia are specifically involved in limb patterning.
  • option_b: The class affecting both limb and kidney development, because monocilia are thought to be involved in broader signaling pathways that influence multiple organs.
  • option_c: Both classes equally, as monocilia are generally involved in all developmental processes.
  • option_d: Neither class, as monocilia are primarily involved in cell division, not organ development.

Explanation

The question about monocilia is a direct follow-up to the text discussing 'positional information' and 'signaling molecules.' Monocilia are cellular antennae involved in receiving and transducing various extracellular signals, playing critical roles in developmental pathways. If a mutation affects multiple distinct organs limb and kidney , it suggests a defect in a fundamental signaling pathway that is shared across these developmental processes, which is characteristic of the broad roles of monocilia. A mutation affecting only a single organ limb might point to a more specific, localized defect, potentially downstream of monocilia signaling, or involving other limb-specific factors.