In Humans freckles (F) is dominant to no freckles (f). If A man and woman both have freckles and they have a child with no freckles what must be the genotype of the parents?

The genotype of the parents is Ff and Ff.

Explanation:

Data given:

freckles = dominant, FF or Ff genotype

no freckles = recessive, ff

genotype of parents with freckles = ?

child has no freckles = ?

The possibility of the child having no freckles is because the parent could be heterozygous dominant for the trait i.e freckles.

The genotype is Ff X Ff

        F        f

F     FF     Ff

f       Ff     ff

It can be seen from the Punnet square that there are 25% chance of the child to be with no freckles when both parents are having freckles.

The genotype ratio is 1:2:1

The phenotype ratio is 3:1

3 with freckles and 1 with no freckles.

ff

Explanation:

Just got it right on Ap3X

before, trains worked using the steam engine. thus, it uses heat so it is crucial to apply heat balance. the steam engine absorbs energy during the stage of boiling water. so, this is the endothermic reaction. when the steam is used to work the piston, it has to release this energy through running the train. the excess energy is released as an exhaust to the chimney. this is the exothermic process because it releases energy to the surroundings.