Final answer:
Immediately after fusion of a mouse and human cell treated with green and red fluorescent antibodies, the cell shows an intermingled patchy distribution of the two colors, rather than a uniform mix or clear division, due to the antibodies binding to their respective cell surface proteins.
Step-by-step explanation:
When a mouse cell and a human cell are fused and then treated with specific antibodies covalently linked to fluorescent dyes (green for mouse proteins and red for human proteins), the distribution of these antibodies across the surface of the hybrid cell helps us understand the fluidity of the cell membrane. Immediately after fusion, before the proteins have had the chance to diffuse and mix, the antibodies will bind to their respective cell surface proteins. Thus, the cell would not be half red and half green, nor would it appear yellow or brown, which would indicate a complete and homogeneous mixing.
Instead, the correct answer is that the red and green labels are distributed in intermingled patches across the membrane (distribution in patches), rather than being uniformly distributed or separated into halves. This is because the membrane proteins have not yet moved significantly from where they originated, giving the appearance of a mixed pattern. Over time, due to the fluid nature of the cell membrane, the red and green labels would begin to diffuse across the cell surface which would eventually lead to uniform distribution, with overlapping areas potentially appearing yellow under fluorescent lighting due to the combination of the red and green dyes.