Difficulty: Easy
Correct Answer: Plant cells stripped of their cell wall (protoplasts)
Explanation:
Introduction / Context:Somatic hybridization allows fusion of plant cells from the same or different species to combine nuclear and cytoplasmic genomes, creating novel hybrids and cybrids. The prerequisite is removing rigid cell walls to permit membrane–membrane contact and fusion.
Given Data / Assumptions:
Concept / Approach:Protoplasts are naked plant cells bounded only by the plasma membrane. They can be fused chemically (e.g., polyethylene glycol, PEG) or by electrofusion (short electric pulses). After fusion, hybrid cells are cultured to regenerate cell walls and whole plants via tissue culture, enabling transfer of traits like cytoplasmic male sterility or disease resistance.
Step-by-Step Solution:
Isolate target tissues; enzymatically digest walls to generate many protoplasts.Select and purify viable protoplasts by density or filtration.Induce fusion using PEG or electric fields.Culture fused cells on regeneration media to form callus and then plants.Verification / Alternative check:Microscopy confirms wall removal (spherical morphology) and fusion events (heterokaryons). Regenerated plants can be genotyped to verify hybrid status.
Why Other Options Are Wrong:
Common Pitfalls:Neglecting the need for osmotic stabilization of protoplasts during handling; lysis is common without proper osmolarity control.
Final Answer:Plant cells stripped of their cell wall (protoplasts)
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