Final answer:
Loss of function mutations in proto-oncogenes are usually recessive and can interfere with cell cycle progression and prevent cell division. They do not create oncogenes, which result from gain of function mutations.
Step-by-step explanation:
Loss of function mutations in proto-oncogenes do not result in the formation of oncogenes but rather diminish the function of these cell-cycle regulators. Therefore, answer A is incorrect because oncogenes are typically associated with gain of function mutations that increase the activity of a proto-oncogene, leading to uncontrolled cell proliferation. Let's assess the options provided:
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- C. Are recessive - Typically, loss of function mutations in proto-oncogenes are not dominant; their effects tend to be recessive because a single functional copy of the gene can often maintain normal cellular function.
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- F. Prevent cells from progressing to the next stage of the cell cycle - Since proto-oncogenes normally promote cell division, loss of their function may indeed interfere with cell cycle progression.
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- G. Prevent cell division - If the cell cycle cannot progress, this can prevent cell division.
Answers B, D, E, H, I, J, and K are incorrect because they do not typically apply to loss of function mutations in proto-oncogenes. Such mutations don't lead to the formation of oncogenes (B), they are usually recessive rather than dominant (D), and can be inherited if the organism with the mutation can still reproduce (J). They do not promote progression to the next stage of the cell cycle (H) or promote cell division (I), and viability of progeny carrying the mutation depends on several factors, making K too absolute of a statement.