$A$ person may have one gene for normal haemoglobin and one gene for sickle cell haemoglobin. This heterozygous condition is called:

Which of the following is genetically dominant in man?

Which of the following statements are false?
$I.$ $A$ dominant allele determines the phenotype when paired with a recessive allele.
$II.$ $A$ recessive allele is weaker than a dominant allele.
$III.$ $A$ recessive allele does not show its effects when paired with a dominant allele.
$IV.$ $A$ dominant allele is always better for an organism.

$A$ hereditary disease,which is never passed on from father to son,is:

In a dihybrid cross,when one pair of alleles shows incomplete dominance,the resulting genotypic ratio will be ....

Give differences: Incomplete dominance and Co-dominance.