Which of the following is found in eukaryotic cells but not in prokaryotic cells?

A. growing corn plants with various amounts of fertilizer: Using corn plants introduces a different species, which makes results irrelevant to the effect of fertilizer on tomato plants.

B. growing tomato plants with various amounts of fertilizer: This is part of the experimental group rather than a control, as it tests different fertilizer levels rather than providing a baseline for comparison.

C. growing corn plants without fertilizer: Corn plants are not suitable because the research question focuses on tomato plants. A valid control must match the species being studied.

D. growing tomato plants without fertilizer: This is the correct control, as it provides a baseline growth rate for tomato plants without fertilizer, allowing meaningful comparison with fertilized groups.

A. Synthesis: After entry, the viral genome directs the host cell machinery to synthesize viral nucleic acids and proteins. This step comes after attachment and entry, not at the beginning.

B. Assembly: Once viral components are synthesized, they are assembled into complete virions. This occurs later in the cycle, just before release.

C. Attachment: The first step is the virus binding to specific receptors on the host cell surface, initiating infection. This allows the virus to target a suitable host cell.

D. Entry: After attachment, the viral nucleic acid or entire virion enters the host cell through mechanisms like endocytosis or membrane fusion. This is the second step.

E. Release: The final stage is when mature virions exit the host cell, often by lysis in bacteriophages or budding in enveloped viruses, enabling them to infect new cells.