Gene Dominance and Allelic Expression — NEET Biology
🔥 Predicted for NEET 2027Explanation of the concept of dominance: What exactly is dominance? Why are some alleles dominant and some recessive? To tackle these questions, we must understand what a gene does. Every gene, as you know by now, contains the information to express a particular trait. In a diploid organism, there are two copies of each gene, i.e., as a pair of alleles. Now, these two alleles need not always be identical, as in a heterozygote. One of them may be different due to some changes that it has undergone (about which you will read further on, and in the next chapter) which modifies the information that particular allele contains.
Adjacent to a frequently-asked paragraph in the same chapter.
In Antirrhinum (Snapdragon), a red flower was crossed with a white flower and in F₁ generation all pink flowers were obtained. When pink flowers were selfed, the F₂ generation showed white, red and pink flowers. Choose the incorrect statement: (NEET 2019)
View solution & NCERT explanation
Correct answer: A — Law of segregation does not apply in this experiment.
The Law of Segregation still applies in this case. Each allele segregates during gamete formation. However, since red is not completely dominant over white, incomplete dominance is observed, and heterozygous (Rr) flowers are pink. The phenotypic ratio becomes 1 red : 2 pink : 1 white.
What does NCERT say about Explanation concept dominance What?
Has this concept appeared in NEET?
Which chapter is this from?
Through deep analysis of NEET and NTA, 176 of the 180 ReNEET 2026 (June 21) questions were already in the MedicNEET question bank before the exam.
176/180MedicNEET's Biology question bank is built from the same NCERT lines NTA picks repeatedly. Not random MCQs — questions crafted exactly like NTA crafts them.