Aman who smokes heavily has developed lung cancer. the tobacco smoke has caused mutations in some of the cells in his lungs, making them unable to stop reproducing and dividing. he is worried that his children, none of whom smoke, may have inherited the lung cancer from him. under what circumstances might his concern for his children be justified? if his smoking had already mutated the dna in the cells in his lungs at the time his children were conceived, the mutations would have been passed to his children. if he inherited a mutation which made him more susceptible to lung cancer, it may have been present in some of the gametes he produced and passed to his children. if the mutation resulted from the duplication of a gene in his lung cells, his children would be at greater risk than if it were caused by a base pair substitution. if the smoke had caused multiple different mutations in his lung cells, it would be more likely that one or more of the mutations would be passed to his children.

The correct answer is "If he inherited a mutation which made him more susceptible to lung cancer, it may have been present in some of the gametes he produced and passed to his children".

Explanation:

Lung cancer is a complicated disease that could be developed by both, environmental and genetic factors. However, lung cancer has been more widely associated with environmental factors, which the inheritance accounting for only 8% of the cases. In this case a man who smokes heavily has developed lung cancer and is worried that his non smoker children may developing it as well. His worries may be justified only If he inherited a mutation which made him more susceptible to lung cancer, it may have been present in some of the gametes he produced and passed to his children. This seems very unlikely since the patient smokes heavily and most likely developed lung cancer from this practice, however genetic tests should be performed to corroborate this.

the electromagnetic spectrum includes, from longest wavelength to shortest: radio waves, microwaves, infrared, optical, ultraviolet, x-rays, and gamma-rays.

you are certainly talking about this picture:

a: is the label of the white square, it is showing the  replication fork, formed by helicase (d) ==> so it is the site of dna separation and replication 

b: is a new dna brand that is following directly the replication fork, so it is continuous ==> built continuously from 5' to 3

c: dna polymerase cannot replicate dna on its own, it needs the of their proteins, and one of them plays the role of a clamp which fixes  the dna with the dna template and increases  the processivity of the enzyme. ==>   stops polymerase from falling off the  template.

d: is the enzyme responsible for forming the replication fork (helicase) ==> unwinds and separates dna into two strands

e: is the delayed strand, it is built  in the opposite sense of the helicase, so dna will be built in fragments ==> built  fragments from 5' to 3 joins

and finally f: is the enzyme that builds  the new dna strand (dna polymerase) ==>   adds nucleotides to make a new dna helix.

credit: gradman555p98x9p

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