Question: In humans, the gene for a free earlobe [E] is dominant over the gene for an attached earlobe [e]. If one parent has a free earlobe [ Ee ] and the other parent has an attached earlobe ( ee ), what is the probability that their offspring will have an attached earlobe?
Answer: 50%
Hypothesis: the offspring will have a 50% probability to have an attached earlobe
Supporting facts: sent1: the other parent is homozygous recessive in earlobe sent2: genes are located on chromosomes sent3: inheriting is when an inherited characteristic is copied / is passed from parent to offspring by genetics / dna sent4: a homozygous dominant organism contains only dominant genes sent5: genetic / hereditary means of genes / heredity sent6: likelihood is similar to probability sent7: parents produce offspring sent8: traits can be determined by one pair / many pairs of genes in an organism sent9: if both recessive genes are present , then the recessive trait will be visible / expressed sent10: ability is a property of things and includes ordered values of able / unable / can / cannot sent11: genes are able to determine the inherited characteristics of a living thing sent12: crossing / breeding a homozygous dominant organism with a homozygous recessive organism causes all their offspring to be heterozygous dominant sent13: one parent is heterozygous dominant in earlobe sent14: a homozygous recessive organism contains only recessive genes sent15: both means two sent16: if both dominant genes are present , then the dominant trait will be visible / expressed sent17: genes contains genetic information sent18: if the offspring of two parents have both dominant and recessive trait , then the parents have different alleles for that trait sent19: genetic variation in offspring has a positive impact on an organism 's / offspring 's survival / health / ability to reproduce sent20: trait is synonymous with characteristic sent21: genes is a vehicle for passing inherited characteristics from parent to offspring sent22: the inherited characteristics of the parents can be used to predict inherited characteristics of the offspring sent23: an attached earlobe is a recessive trait in human sent24: crossing a heterozygous dominant organism with a homozygous recessive organism causes their offspring to be homozygous recessive of 50% probability sent25: dna are a vehicle for passing genes from parent to offspring
Reasoning: [BECAUSE] the other parent is homozygous recessive in earlobe [AND] one parent is heterozygous dominant in earlobe [AND] crossing a heterozygous dominant organism with a homozygous recessive organism causes their offspring to be homozygous recessive of 50% probability [INFER] int1: the offspring will have a 50% probability to be homozygous recessive [BECAUSE] an attached earlobe is a recessive trait in human [AND] if both recessive genes are present , then the recessive trait will be visible / expressed [INFER] int2: to have an attached earlobe requires the human to have both recessive genes [BECAUSE] int2 [AND] a homozygous recessive organism contains only recessive genes [INFER] int3: to have an attached earlobe requires the human to be homozygous recessive [BECAUSE] int1 [AND] int3 [INFER] int4: the offspring will have a 50% probability to have an attached earlobe