Question

chapter 8: chromosomes and human genetics: curing the incurable
8.5. compare and contrast the inheritance of recessive, dominant, and sex - linked genetic disorders.
complete the passage regarding inheritance of genetic conditions in humans.
analyzing the pattern of inheritance for a genetic condition can help determine the mode of inheritance. if a genetic condition is not present in either parent but is sometimes inherited by their offspring, the condition is likely. if a genetic condition is not present in either parent, it is never inherited by their offspring. but when either parent is affected by the condition, their offspring have at least a 50% chance of inheriting it and the condition is likely. if a genetic condition is more readily expressed by male offspring than female offspring, the condition is likely.
autosomal recessive autosomal dominant sex - linked*

Explanation:

1. For autosomal - recessive conditions, parents can be carriers (not show symptoms) and pass the recessive allele to offspring. So, a condition not present in parents can be inherited by offspring.
2. In autosomal - dominant conditions, if a parent has the dominant allele (and thus the condition), there is at least a 50% chance of passing it to offspring. If neither parent has it, offspring won't inherit it.
3. Sex - linked conditions often affect males more readily because males have only one X - chromosome. If the recessive allele is on the X - chromosome, males are more likely to express it compared to females who have two X - chromosomes.

Answer:

1. autosomal recessive
2. autosomal dominant
3. sex - linked