The genotypes of a husband and wife are \(I^AI^B\) and \(I^Ai\). Among the blood types of their children, how many different genotypes and phenotypes are possible?

A \(3\) genotypes; \(4\) phenotypes
B \(4\) genotypes; \(3\) phenotypes
C \(4\) genotypes; \(4\) phenotypes
D \(3\) genotypes; \(3\) phenotypes

Verified Solution

Answer & Solution

Correct Answer

(B) \(4\) genotypes; \(3\) phenotypes

Step-by-step Solution

Detailed explanation

(b): If the genotypes of husband and wife are \(I^AI^B\) and \(I^Ai\) respectively, then the probabilities of genotypes and phenotypes among their children can be worked out as:

Genotype:	\(I^A I^A\)	\( I^Ai\)	\( I^AI^B\)	\(I^Bi\)
Phenotype:	\(A\)	\(A\)	\(AB\)	\(B\)

Thus, there are four possible genotypes, viz., \(I^AI^A, I^Ai, I^AI^B\) and \(I^Bi\) and three possible phenotypes, viz., \(A, AB\) and \(B\) among the children.

Apply the relevant identity from the chapter and substitute the values established in the previous step, keeping the original constraint in view.

Use the simplified expression to isolate the unknown, then plug the result back into the question setup to confirm the working is internally consistent.

Cross-check against a boundary or limiting case. Both the dimensional balance and the qualitative behaviour at the extreme should agree with the candidate answer.

Combine the steps above to identify the correct option. The remaining choices each fail at least one of the consistency, dimensional, or boundary checks.

Same subject

Match the items given in Column \(I\) with those in Column \(II\) and select the correct option given below:

Column \(I\)	Column \(II\)
\((a)\)Tidal volume	\((i)\) \(2500-3000\,mL\)
\((b)\)Inspiratory Reserve volume	\((ii)\) \(1100 -1200\,mL\)
\((c)\)Expiratory Reserve volume	\((iii)\) \(500 -550\,mL\)
\((d)\) Residual volume	\((iv)\) \(1000-1100\,mL\)

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