Final answer:
A filled-in square represents a diseased male in a pedigree chart. The filling in of the square indicates that the male individual has the symptom of the disease. The inheritance of the disease in offspring depends on the disease inheritance pattern.
Step-by-step explanation:
In pedigree charts, ways of presenting information about an individual's family history, the symbol for a diseased male is indeed a filled-in square.The likelihood of male and female offsprings inheriting the condition are often dependent on the inheritance pattern of the disease.
This is because squares represent males in these diagrams, and when a square is filled in, it indicates that the individual is presenting traits or symptoms of a particular condition, such as neonatal ALD as mentioned in your question.
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