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1.3 Induction — Test 1
Q1. The embryonic process in which one tissue influences the developmental fate of another is called:✓ Induction
Q2. The ability of a cell to respond to a specific inductive signal is called its:✓ Competence
Q3. An inductive interaction in which the signal directs the responding cell toward a specific fate is described as:✓ Instructive
Q4. A permissive inductive interaction is one in which the signal:✓ Allows a cell with an already-determined fate to express it
Q5. Signalling that requires direct physical contact between adjacent cells (e.g. via membrane-bound ligands) is:✓ Juxtacrine signalling
Q6. Signalling by a diffusible factor that acts on nearby cells is called:✓ Paracrine signalling
Q7. Lateral inhibition, in which one cell adopts a fate and prevents its neighbours from doing the same, produces:✓ A regularly spaced pattern of differentiated cells
Q8. Notch–Delta signalling is a classic example of:✓ Juxtacrine signalling and lateral inhibition
Q9. In the chick, wing, thigh and claw feathers develop because the dermis from different regions induces the epidermis differently. This illustrates:✓ Regional specificity of induction
Q10. When frog ectoderm transplanted into a newt's mouth region forms frog-type mouthparts (suckers), this shows:✓ Genetic (species) specificity of induction
Q11. Competence is best described as:✓ The ability of a tissue to respond to an inducing signal
Q12. An instructive induction differs from a permissive one mainly because the instructive signal:✓ Determines which specific fate the responding cell adopts
Q13. Cadherins are important in development because they mediate:✓ Calcium-dependent cell–cell adhesion
Q14. A morphogen exerts its effect on cells mainly through:✓ A concentration gradient that specifies different fates at different levels
Q15. The Spemann–Mangold organizer acts on neighbouring tissue by:✓ Induction (instructing it to form dorsal/neural structures)
Q16. Reciprocal induction, as in kidney development, means that:✓ Two tissues each induce changes in the other
Q17. The signalling pathway in which a membrane-bound ligand on one cell activates a receptor on an adjacent cell, central to lateral inhibition, is:✓ The Notch pathway
Q18. Positional information allows a cell to:✓ 'Know' its location in the embryo and differentiate accordingly