There are specific checkpoints in the cell cycle that ensure…
There are specific checkpoints in the cell cycle that ensure the cell is ready to proceed to the next stage. A cell has just finished replicating its DNA. A protein called p53 checks the DNA for damage before allowing the cell to enter mitosis. At which checkpoint is this check most likely to occur?
Read DetailsCarbon-14 is a radioactive isotope of carbon used in carbon…
Carbon-14 is a radioactive isotope of carbon used in carbon dating. The number 14 refers to the total number of protons and neutrons in the atom’s nucleus. Given that the atomic number of carbon is 6, how many neutrons does carbon-14 have?
Read DetailsIn a healthy cell, the cell cycle is regulated by checkpoint…
In a healthy cell, the cell cycle is regulated by checkpoints that prevent the cell from dividing if there is DNA damage. In a cancerous cell, this regulation is often lost. What is a key difference in the way a cancerous cell divides compared to a healthy cell?
Read DetailsA scientist is studying a virus and a bacterium. The bacteri…
A scientist is studying a virus and a bacterium. The bacterium is able to maintain a stable internal environment and uses energy from its surroundings to grow. The virus, on the other hand, cannot maintain its own internal environment and can only reproduce by hijacking a host cell. Based on these observations, which of the following is true?
Read DetailsIn a healthy cell, tumor suppressor genes, like p53, are res…
In a healthy cell, tumor suppressor genes, like p53, are responsible for stopping cell division when there is DNA damage. However, in some cancer cells, these genes are silenced. What epigenetic modification can lead to the silencing of tumor suppressor genes?
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