Neurological signals sent from fear responses in an organism tell the cell to stop. The cell's DNA has been damaged somehow. The cell's DNA was replicated incorrectly.
Explanation:
All the three options given can cause checkpoint genes to interrupt cell division.
Checkpoint genes are transcription genes that control cell cycle and sense defects during cells processes like DNA replication, segregation e.t.c and create response till the defects is repaired in the DNA. The important of checkpoint is that it ensure enough nutrients are available to support for division, ensure that the DNA has not been damaged, ensure that cells DNA is copied correctly and make sure cells have enough RNA for their protein synthesis.
Checkpoints genes can interrupt cell division if the dna is damaged, Dna is copied incorrectly and neurological signal sent from fear responses in an organisms tell the cells to stop.
The flagella of the eukaryotes is composed of the doublet microtubules. The central bundle of these microtubules is known as the anoxeme. In an axoneme, a single pair of the singlet micortubules is surrounded by the nine doublet microtubules. When the plasma membrane of the flagellum is opened to expose the axoneme, and the radial spokes are broken, it will lead to the elongation of the axoneme,