How many genes undergo DNA replication before mitosis?
Answer Dear Julie, When a cell prepares for mitosis, *all* the DNA in the nucleus is replicated. Depending on what species you’re talking about, that could be anywhere from about 1000 genes (in a bacterium) to about 30,000-60,000 for a human (the jury’s still out on how many genes are present in a typical mammal) to 400,000 (in the case of some plants, such as ferns). The easiest answer to your question is: ALL of them. 🙂 Hope that helps.
