1. Tardigrade
  2. Question
  3. Biology
  4. In heterozygous condition, both the alleles express in

Question Error Report

Thank you for reporting, we will resolve it shortly

Back to Question

Q. In heterozygous condition, both the alleles express in

Principles of Inheritance and Variation

Solution:

• The gene $(I)$ has three alleles $I^A, I^B$ and $i$ The alleles $I^A$ and $I^B$ produce a slightly different form of the sugar while allele $i$ doesn’t produce any sugar.
• Because humans are diploid organisms, each person possesses any two of the three $I$ gene alleles.
• $I^A$ and $I^B$ are completely dominant over $i$, in other words when $I^A$ and $i$ are present only $I^A$ expresses (because $i$ does not produce any sugar), and when $I^B$ and $i$ are present $I^B$ expresses.
• But when $I^A$ and $I^B$ are present together they both ex press their own types of sugars: this is because of co dominance. Hence red blood cells have both $A$ and $B$ types of sugars.